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Algorithms

Specification of .analytic's analysis algorithms, their benefits, and application.

Overview

Analytics pursues only one goal: Guiding technicians and building users to improve the operational performance of buildings and energy systems, while the benefits of improved operational performance are multilateral:

  • Higher comfort, means higher well-being and therefore performance of people in buildings.
  • Higher energy efficiency providing comfort and energy services.
  • Lower effort maintaining and servicing complex technical facilities.

This page offers specifications on the available analysis functions. Each specification starts with an introduction to the analysis, followed by tabs providing deeper insights and application notes. Browse the tabs for insights in the analysis specifications.

This tab summarizes the value offered by the analysis function, the component types the analysis is recommended for, and the conditions checked by the analysis.

In general, you can expect a short case-study on how the analysis function was applied during development or a test bench.

Results of analytics functions are structured to deliver simple-to-navigate insights and fast-to-apply measures on how to improve operational performance.

Therefore, each result regardless of the analytics function includes

  • One qualitative warning level, aka. traffic light color,
  • One interpretation,
  • Zero to n recommendations,
  • Zero to n KPIs, and
  • Zero to n timeseries.

These categories are explained below. While the warning level, interpretation, and recommendation are specified for all analysis functions equally, KPIs and time series differ between each analysis function.

Warning level

The warning level represents the urgency of looking into the analyzed condition and taking action to improve it. It can have one of these traffic light states, but not every analysis makes use of the full spectrum:

Red: Suboptimal performance identified. It can be expected that either improving the identified condition will have a strong effect on the performance or the effort to realize the optimization is moderate compared to its benefit.

Yellow: Suboptimal performance identified. The effort to optimize might consume its benefit. To reduce the effort, implement the measure with the maintenance work that is required anyway. Observation of the analyzed condition is recommended.

Green: Performance is satisfactory. No action is recommended.

Interpretation

The interpretation delivers a summary of the observed performance and state of the condition analyzed. It describes either a symptom of a suboptimal operation or a condition that could be identified.

Recommendation

Recommendations are summarized in a list of zero (for sufficient operational performance) to n measurements on how to improve the operational performance. The recommendations either help by providing information on how to correct the source of the symptom itself or on how to narrow down to its root cause.

KPIs and time series

KPIs and time series offer insights and transparency. They enable reporting and manual investigation of the operational behavior of the component or system analyzed. KPIs and time series are highly individual for each function and are explained in the respective specification of each analysis function in Results.

The Components tab contains the API identifier and information of

  • The components the analysis function is available for,
  • The pins of the components which need to be mapped, and
  • The attributes of the component required.

The Application tab provides information on the application of the analysis function.

  • Recommended time span: Most of the analysis functions have a sweet spot for the amount of historical data required to derive accurate results.
  • Recommended repetition: Components of building energy systems are subject to seasonal effects and wear out. Follow the recommended repetition to ensure the analysis is performed as often as necessary, without risking blind spots during the continuous monitoring of the system.

Analysis functions

See below for the individual analysis function specification.

Alarm State Analysis

The Alarm State Analysis assesses the occurrences and duration of alarm messages of a component. It is particularly useful for notifying the user when alarm messages have been overseen, as it summarizes the alarm messages over a given time period. Additionally, the Alarm State Analysis considers the most recent alarm message to determine whether the error has been resolved. While this analysis can be used for all alarm messages, it is most suited to critical alarm messages.

Value

  • Avoids alarm messages being overlooked
  • Identifies faulty components
  • Can reduce component wear-and-tear
  • Can increase energy efficiency

Recommended for components

Any component or subsystem which could have an alarm or error message such as:

  • Fans
  • Heat pumps
  • Thermal control loops

Checked conditions

  • Last state of alarm message
  • Relative duration of alarm message
  • Total duration of alarm messages
  • Total occurrences of alarm message

The Alarm State Analysis was performed on a component for February 2020. The error message is active at the beginning of the time period and then about twice a week after that.

alarm-state-analysis
Figure 1: Component error message for the month of February 2020

The analysis returns a red warning message to indicate that the error message over the time period is suboptimal. This is because the error message is active for a significant percentage of the total time.

KPI Value Unit
alarm message.last observation inactive binary
alarm message.relative 25.4 %
alarm message.duration 164 h
alarm message.count 12 count

Signal colors

Signal color Available Info
red Yes The occurrences or alarm message duration is very high.
yellow Yes The occurrences or alarm message duration are acceptable.
green Yes The occurrences and alarm message duration are insignificant.

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Check the component for physical damage and consider changing the component setting.

KPIs

Summary of alarm messages

KPI Identifier Description Value Range Unit
alarm message.last observation Last available alarm message. Active, Inactive binary
alarm message.relative Time of active alarm message as a percentage of total time. 0 to 100 %
alarm message.duration Total time of active alarm message. 0 to inf h
alarm message.count Occurrences of the alarm message. 0 to inf count

Boiler

Pin Required Mapping info
Alarm message Yes -

Combined heat and power

Pin Required Mapping info
Alarm message Yes -

Fan

Pin Required Mapping info
Alarm message Yes -

Heat pump

Pin Required Mapping info
Alarm message Yes -

Thermal control loop

Pin Required Mapping info
Alarm message Yes -

Recommended Time Span

1 month


Recommended Repetition

Every month

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance of replacements

Control Loop Oscillation Analysis

The Control Loop Oscillation Analysis checks the process value of a control loop for oscillation. Oscillating process values are an indicator for suboptimal parameterization or structural dimensioning of the control loop.

Value

  • Increase lifetime of valve, dampers, and adjacent components
  • Avoid spontaneous failures
  • Reduce energy consumption
  • Reduce noise pollution

Recommended for components

Any liquid media supply system, such as:

  • Thermal control loop with 2-way valve and pump

Checked conditions

  • Process value of the control loop is oscillating
  • Process value of the control loop is not or to a negligible degree oscillating
  • Condition checks on times of components operation

For this example, we analyzed the temperature control loop of a supply air volume flow, which provides fresh air and heating to a large salesroom. Figure 1 shows a plot of the process value of the control loop, the outlet temperature. The plot shows an oscillation of the outlet temperature during periods of operation.

oscillating-control-loop
Figure 1: Oscillating processes value during operation

Figure 2 is a zoom of figure 1 to analyze the oscillation in more detail. The trajectory of the process value is common for control loops oscillating at medium frequency.

oscillating-control-loop-zoom
Figure 2: Oscillating process value during operation in detail

The Control Loop Analysis evaluated this oscillation as significant and assigned it the signal color yellow. Recommendations are made on how to adjust controller parameters for a smoother operation.

Signal colors

Signal color Available Info
red No Red as a signal for a low cost measure with high impact on the building operation will not be provided.
yellow Yes An oscillating control loop is a symptom for suboptimal control parameters or component design. Investing the extra effort to identify the root cause and fixing it is strongly recommended.
green Yes No or only slight, in respect to usual tolerances in buildings, negligible oscillation.

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations on how to smooth the control loop oscillation. No recommendation, if oscillation is negligible

Cooling circuit

Pin Required Mapping info
Operating message No Strongly recommended Default: Always on
Supply temperature Yes -

Heat transfer unit

Pin Required Mapping info
Operating message No Strongly recommended Default: Always on
Supply temperature - secondary Yes -

Heating circuit

Pin Required Mapping info
Operating message No Strongly recommended Default: Always on
Supply temperature Yes -

Thermal control loop

Pin Required Mapping info
Operating message No Strongly recommended Default: Always on
Outlet temperature Yes -

Recommend Time Span

1 day to 1 week


Recommended Repetition

Weekly

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Dew Point Alert Analysis

Building automation systems often have dew point alert messages which identify the possibility of unwanted condensation taking place in rooms. If the dew point alert message is active for any amount of time during the period of analysis, a recommendation is made to the user since rooms condensation in rooms can be damaging. Furthermore, if the temperature and relative humidity of the room are known, the Dew Point Alert Analysis calculates the risk of condensation and takes these into account in the evaluation. The Dew Point Alert Analysis is recommended for any room with an existing dew point alert signal or with temperature and relative humidity sensors.

Value

  • Avoids damage to rooms due to condensation

Recommended for components

  • Rooms

Checked conditions

  • Duration of dew point alert signal
  • Duration in which the room temperature is between 2 °C and 4 °C above the dew point temperature
  • Duration in which the room temperature is within 2 °C of the dew point temperature

The Dew Point Alert Analysis was performed on a room for a week in February 2020. For this particular room, a dew point alert message is available but no temperature and relative humidity data. As is shown in figure 1, the dew point alert signal is only active for a very short amount of time during the week.

dew-point-alert-analysis
Figure 1: Dew point alert for one week in February 2020

The analysis returns a red warning message to indicate that the dew point alert was active during a portion of the time period. This suggests that the condensation may have formed in the room. Note that only "dew point alert" KPIs are generated since no temperature and humidity data are available in this example.

KPI Value Unit
dew point alert message.relative 1.69 %
dew point alert message.duration 2.83 h

Signal colors

Signal color Available Info
red Yes Dew point alert message is active for some time or the temperature and humidity show a high chance of condensation.
yellow Yes There is a moderate chance of condensation taking place in the room.
green Yes Dew point alert message is not active during analysis period. No risk of condensation.

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Check the room for condensation and mold.

KPIs

The KPIs which are generated by this analysis depend on the information available in the analysis. The "dew point alert message" KPIs are generated if a dew point alert message is available. The condensation risk KPIs are generated using room temperature and relative humidity.

The condensation risk is evaluated as moderate if the room temperature is between 2 K and 4 K above the dew point temperature. A high condensation risk is when the room temperature is within 2 K of the dew point temperature.

Dew point alert

KPI Identifier Description Value Range Unit
dew point alert message.relative Time of active dew point alert message as a percentage of total time. 0 to 100 %
dew point alert message.duration Total time of active dew point alert message. 0 to inf h
condensation risk moderate.relative Time of moderate condensation risk as a percentage of total time. 0 to 100 %
condensation risk moderate.duration Total time of moderate condensation risk. 0 to inf h
condensation risk high.relative Time of high condensation risk as a percentage of total time. 0 to 100 %
condensation risk high.duration Total time of high condensation risk. 0 to inf h

Room

Pin Required Mapping info
Dew point alert message No The dew point alert message can be used as the only pin or in combination with temperature and humidity.
Temperature No If the temperature is mapped, humidity must also be mapped. Can be used in combination with the dew point alert message.
Humidity No If humidity is mapped, the temperature must also be mapped. Can be used in combination with the dew point alert message.

Recommend Time Span

1 week to 1 month


Recommended Repetition

Every month

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance and replacement

Energy Conversion Analysis

The Energy Conversion Analysis evaluates the quality of the energy conversion of a component, based on efficiency indicators. It is useful to detect inefficient operational states. Furthermore, information is provided regarding which part of the plant is responsible for the malfunction and what could be done to resolve the problem.

Value

  • Reduced operational costs
  • Detection of broken components

Recommended for components

  • Combined heat and power

Checked conditions

The Energy Conversion Analysis was applied to a real combined heat and power plant and the pins operating message, generator power, heat flow, and fuel power were mapped. Figure 1 shows the time series recorded for an exemplary period of 7 days. The grey shaded periods correspond to the operation of the plant.

energy-conversion-analysis
Figure 1: Period of one week for which the energy conversion is not acceptable

A very low generator power compared to the heat flow and the fuel power indicates a failure of the generator component. The automated interpretation confirms our visual analysis of the time series shown in the figure, summed up by the qualitative warning level “red”. It also provides recommendations to address the problem.

KPI Value Unit
generator power.mean 9.4 kW
heat flow.mean 640.9 kW
fuel power.mean 1940.3 kW
power to heat ratio 1.47 %
fuel utilization factor 33.5 %
thermal efficiency 33.0 %
electric efficiency 0.485 %

Signal colors

Signal color Available Info
red Yes The quality of the energy conversion is not acceptable.
yellow Yes The quality of the energy conversion is suboptimal.
green Yes The quality of the energy conversion is good.

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations to improve energy conversion. No recommendation, in case of good energy conversion.

KPIs

Energy Performance KPIs

KPI Identifier Description Value Range Unit
generator power.mean Average generator power 0 to inf kW
fuel power.mean Average fuel power 0 to inf kW
power to heat ratio Cumulated electrical energy divided by the cumulated heat energy 0 to inf %
fuel utilization factor Total efficiency of the plant (i.e., total heat and power divided by total energy provided by the fuel energy). 0 to 100 %
thermal efficiency Cumulated heat energy divided by the total fuel energy. 0 to 100 %
electrical efficiency Cumulated electrical energy divided by the total fuel energy. 0 to 100 %

Combined heat and power

Pin Required Mapping info
Operating message No -
Generator power Yes -
Heat flow Yes -
Rate of fuel consumption No -
Attribute Required Mapping info
Fuel price No Default: 0.06 €/kWh Gas
Electricity price No Default: 0.18€/kWh
Heat price No Default: 0.065 €/kWh
Generator nominal power No -
Nominal heat production No -

Recommended Time Span

1 day to 1 week


Recommended Repetition

Every month

Fan Speed Analysis

The Fan Speed Analysis evaluates whether a fan is controlled, based on its fan speed. This helps to identify problems with fan control and ensures that fans are implemented more energy efficiently.

Value

  • Detect AHU fans that are not controlled
  • Reduce costs through better fan speed control

Recommended for components

  • Fan

Checked conditions

  • Stationary fan speed

In this example, we look at a Fan Speed Analysis of the historic 7-day fan speed. While the Operating Message (grey in the plot below) shows the times when the fan was operated, the fan speed (blue in the plot below) corresponds to the speed or load setting of the fan.

fan-speed-analysis
Figure 1: Speed and operating message of a 7 day fan speed analysis

From the analysis results, we can see that the fan was operated for 6 hours out of the 168 hours of the week or 3.57 % of the week. Additionally, we get statistics of the fan speed, e.g., the fan was operated at an average of 40 % load.

This corresponds to a static fan speed setting that is currently not controlled. To improve energy efficiency and thermal comfort you can consider different control strategies outlined in the recommendations.

KPI - Statistics

KPI Value Unit
operating time 6 h
operating time.relative 3.57 %
speed.maximum 40 %
speed.minimum 40 %
speed.mean 40 %
speed.median 40 %

Signal colors

Signal color Available Info
red No -
yellow Yes Fan speed is not controlled
green Yes Fan speed is controlled

Interpretations

Available Info
Yes Information about the fan speed

Recommendations

Available Info
Yes Recommendations to look into the different control options for this fan to save energy.

KPIs

Statistics

statistics for "speed" will be calculated for all measured values that are not 0 %

KPI Identifier Description Value Range Unit
operating time Total time of operation 0 to inf h
operating time.relative Time of operation in relation to analysis period 0 to 100 %
speed.maximum Largest observation recorded of fan speed during analysis period 0 to 100 %
speed.minimum Smallest observation recorded of fan speed during analysis period 0 to 100 %
speed.mean Time-weighted average of fan speed 0 to 100 %
speed.median Time-weighted median of fan speed 0 to 100 %

Fan

Pin Required Mapping info
Operating message No -
Speed Yes Use this pin to connect the datapoint that reflects fan speed settings from 0 - 100 % load

Recommended Time Span

1 week


Recommended Repetition

Every month

Filter Servicing Analysis

The Filter Servicing Analysis predicts when a filter is due to be serviced or replaced, based on filter contamination or the pressure difference over the filter. This ensures that filters always function optimally and are maintained or replaced as required.

Value

  • Ensures filter is serviced when required
  • Improves energy efficiency

Recommended for components

  • Filter

Checked conditions

  • Filter contamination
  • Expected time till filter service or replacement

In this example, the filter contamination of an exhaust air filter of an air handling unit was analyzed over a period of four months. As can be seen in figure 1, filter contamination gradually increases over the analyzed period.

filter-servicing-analysis
Figure 1: Filter contamination over a four month period

The signal analysis returns a green signal color since there is a significant amount of time before the filter is fully contaminated.

KPI Value Unit
days until filter service 35 d
expected date of filter service 2020-05-20 date
filter contamination 79.3 %

Signal colors

Signal color Available Info
red Yes The filter is fully contaminated and should be serviced soon.
yellow Yes The filter is almost contaminated, a filter service should scheduled.
green Yes The filter is in a good condition and does not need to be serviced.

Interpretations

Available Info
Yes Information regarding the filter condition and whether the filter needs to be serviced.

Recommendations

Available Info
Yes Make necessary arrangements for the filter to be serviced. No recommendation if the filter does not need servicing within two weeks and the filter contamination is below 95%.

KPIs

KPI Identifier Description Value Range Unit
days until filter service Number of days until filter expected filter service. 0 to inf d
expected date of filter service Date on which filter is expected to require a service (format: YYYY-MM-DD) - date
filter contamination Relative extent to which filter is contaminated. 0 to 100 %

Filter

Pin Required Mapping info
Filter contamination No Either filter contamination (preferred) or pressure difference must be mapped. If both pins are mapped, filter contamination is used.
Pressure difference No Either filter contamination (preferred) or pressure difference must be mapped. If both pins are mapped, filter contamination is used.
Attribute Required Mapping info
Filter class No Default: F9
Initial pressure difference No Default: initial pressure difference of filter class (50 Pa for filter class F9).
Final pressure difference No Default: final pressure difference of filter class (300 Pa for filter class F9). Setting this attribute is highly recommended.

Recommended Time Span

1 month to 6 months


Recommended Repetition

Twice a month

Humidity Conditioning Analysis

The Humidity Conditioning Analysis compares the outside air humidity with the actual supply air humidity of the Air Handling Unit (AHU).

This analysis does not take into account air recirculation and humidity recovery modes. Make sure that the system is operated without such operational modes.

Value

  • Detect operating conditions of AHUs that are not appropriate to the outside air conditions
  • Avoids unnecessary changes in humidity, which cost a lot of energy
  • Verifies sufficient supply air humidity

Recommended for components

  • Air handling units with humidity conditioning

Checked conditions

  • Compare actual operating hours with humidification, dehumidification, and no operation with the corresponding expected hours

This example shows a week of analysis for a summer scenario in July. The AHU is operating throughout the week. Relative humidity conditions are displayed in red and orange, green and blue are temperature conditions and brown and purple are the water load conditions.

humidity-conditioning-analysis
Figure 1: Analysis of humidity, temperature and water load conditions over a whole week

The analysis uses two positions, intake (outside conditions) and outlet (supply conditions) to calculate water loads. A difference in these water loads corresponds to the pink line at the bottom. The operating hours will now be divided into three categories. Hours of humidification, hours of dehumidification, and hours of neither humidification nor dehumidification. These values are then compared to the expected hours in these categories derived from outside conditions. The total hours of correct operation (according to the expectation) are then evaluated for a recommendation.

KPI Value Unit
operating time 168 h
operating time.relative 100 %
humidification detected 135 h
dehumidification detected 18 h
humidification necessary 0 h
dehumidification necessary 49 h
humidification missing 0 h
dehumidification missing 49 h
humidification unnecessary 135 h
dehumidification unnecessary 18 h
total hours savings possible.relative 91.1 %
total hours increase air quality.relative 92.3 %

Signal colors

Signal color Available Info
red No -
yellow Yes -
green Yes The AHU operates in accordance to the expected operating conditions.

Interpretations

Available Info
Yes Either the expected operating conditions are met by the operation of the AHU or the operating conditions do not fit.

Recommendations

Available Info
Yes Recommendations regarding which operating mode (humidification, dehumidification) should be looked into to change the operating modes of the AHU.

KPIs

KPI Identifier Description Value Range Unit
operating time Total time of operation 0 to inf h
operating time.relative Total time component was operated compared to analysis period 0 to 100 %

Operating Conditions

KPI Identifier Description Value Range Unit
humidification detected The amount of time the component operates in humidification mode according to inflow/outflow analysis 0 to inf h
dehumidification detected The amount of time the component operates in dehumidification mode according to inflow/outflow analysis 0 to inf h
humidification necessary The amount of time the component should operate in humidification mode according to outside air conditions 0 to inf h
dehumidification necessary The amount of time the component should operate in dehumidification mode according to outside air conditions 0 to inf h
humidification missing The amount of time the component did not operate in humidification mode but should 0 to inf h
dehumidification missing The amount of time the component did not operate in dehumidification mode but should 0 to inf h
humidification unnecessary The amount of time the component operated in humidification mode but should not 0 to inf h
dehumidification unnecessary The amount of time the component operated in dehumidification mode but should not 0 to inf h
total hours savings possible.relative Percentage of time (de)humidification can be switched off according to outside air conditions relative to operating time 0 to 100 %
total hours increase air quality.relative Percentage of time (de)humidification should be switched on according to outside air conditions relative to operating time 0 to 100 %

Humidity conditioner

Pin Required Mapping info
Supply air temperature Yes Conditioned air at supply-side exit of AHU
Supply air relative humidity Yes Conditioned air at supply-side exit of AHU
Outside air temperature Yes Intake air conditions
Outside air relative humidity Yes Intake air conditions
Operating message No Mapping of operating message is strongly recommended.
Default: Always operating

Recommended Time Span

1 week


Recommended Repetition

Every month

  • After changes of operational modes
  • After changes in the control system

Operating Cycle Analysis

The Operating Cycle Analysis identifies excessive start and stop processes which lead to energy losses, energy consumption peaks due to higher energy consumption on plant start, and higher wear-and-tear of the component compared to a constant operation. Further, a frequently alternating operation of a component, e.g., a heat pump, has negative effects on adjacent components, which are enforced to alternate as well. Further, the algorithm takes low cycle rates as an indication of a possible under-supply of the adjacent systems.

Value

  • Lower operating costs
  • Higher energy efficiency
  • Peak energy consumption reduction
  • Longer equipment and component lifetimes
  • Smoother system integration

Recommended for components

Energy conversion plants and components with high start-up energy consumption or wear, such as

  • Heat pump
  • Combined heat and power
  • Boiler
  • Fan

Checked conditions

  • Short cycling of component operation, evaluated component-specific
  • Long cycling of component operation, evaluated component-specific
  • Expected cycling of component operation, evaluated component-specific
  • Condition checks on times of components operation

The Operating Cycle Analysis was applied to a heat pump. Thus, a heat pump component model was instanced and the respective datapoint mapped to the pin operating message. Figure 1 shows the time series recorded for an exemplary period of 1 week in winter.

operating-cycle-analysis
Figure 1: Operating message and cycle behavior of heat pump

Short shut-down times are observed between periods of duty indicating excessive start and stop processes of the heat pump. This not only leads to energy losses and electricity consumption peaks, but also increased wear-and-tear of the heat pump's compressor.

The attributes "Coefficient of performance", "Nominal heat production" and "Electricity price" are set to 4, 1000kW, and 0.18€/kWh. This enables Economic KPIs with the accuracy level "High". The calculations show daily start-up costs of 66 €/d and costs of one start to be 2.75 € (start-up cost).

The automated interpretation confirms our visual analysis of the time series shown in the figure, summed up by the qualitative warning level "yellow". The recommendations provide further instruction on how to isolate and fix the cause for the increased number of start and stop processes. Furthermore, the result offers an advanced set of KPIs, providing additional insights into the cycle behavior of the heat pump.

KPI Value Unit
operating time 84 h
operating time.relative 50 h
starts 168 count
closd operaing cyces 167 count
cycle times.median 1 h
cycle times.mean 1 h
cycle times.maximum 1 h
cycle times.minimum 1 h
duty times.median 0.5 h
duty times.mean 0.5 h
duty times.maximum 0.5 h
duty times.minimum 0.5 h
switch-off times.median 0.5 h
switch-off times.mean 0.5 h
switch-off times.maximum 0.5 h
switch-off times.minimum 0.5 h
start-up costs.daily 66 €/d
start-up costs.weekly 462 €/week
start-up costs 2.75

Signal colors

Signal color Available Info
red No The analysis identifies the symptom and recommends measures to investigate the root cause of short cycling respectively long cycling. Red as a signal for a low-cost measure with a high impact on the building operation will not be provided.
yellow Yes Unwanted cycling rates are a strong symptom for suboptimal control and system performance. Investing the extra effort to identify the root cause and fixing it is strongly recommended.
green Yes Sufficient cycle rates in respect to usual operation in buildings

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations on how to investigate the root cause of an unwanted cycle rate. No recommendation, if cycle rate is sufficient

KPIs

Operating Time and Operating Cycles

KPI Identifier Description Value Range Unit
operating time Total time of operation 0 to inf h
operating time.relative Total time of operation divided by total time span 0 to 100 %
starts Count of starts 0 to inf count
closed operating cycles Count of closed operating cycles. Cycles are counted form start(\(n_i\)) to start(\(n_{i+1}\)) and both starts are within the analysed period 0 to inf count
cycle times.median Median of cycle periods. Not returned in case no closed cycle was observed 0 to inf h
cycle times.mean Time-weighted average of cycle periods. Not returned in case no closed cycle was observed 0 to inf h
cycle times.maximum Longest cycle period. Not returned in case no closed cycle was observed 0 to inf h
cycle times.minimum Shortest cycle period. Not returned in case no closed cycle was observed 0 to inf h
duty times.median Median of duty periods. Not returned in case no closed cycle was observed 0 to inf h
duty times.mean Time-weighted average of duty periods. Not returned in case no closed cycle was observed 0 to inf h
duty times.maximum Longest duty period. Not returned in case no closed cycle was observed 0 to inf h
duty times.minimum Shortest duty period. Not returned in case no closed cycle was observed 0 to inf h
switch-off times.median Median of switch-off periods. Not returned in case no closed cycle was observed 0 to inf h
switch-off times.mean Time-weighted average of switch-off periods. Not returned in case no closed cycle was observed 0 to inf h
switch-off times.maximum Longest switch-off period. Not returned in case no closed cycle was observed 0 to inf h
switch-off times.minimum Shortest switch-off period. Not returned in case no closed cycle was observed 0 to inf h

Economic KPIs

Economic KPIs estimate the economic optimization potentials of the observed operational state. The KPIs indicate the total startup costs based on KPI "starts" and the costs of one cycle of the investigated component.

KPI Identifier Description Value Range Unit
start-up costs.daily Identified daily costs of start-ups. It is provided as the average daily value. 0 to inf €/day
start-up costs.weekly Identified weekly costs of start-ups. It is provided as the average weekly value. This KPI is only provided, if the analyzed time span is at least one week long. 0 to inf €/week
start-up costs Estimation of the cost of one start-up including the shutdown of the device. 0 to inf

The Economic KPIs are provided for the components:

  • Boiler
  • Combined heat and power
  • Heat Pump

Their availability and accuracy depend on the component's mapping. The analysis function always determines the highest possible accuracy.

Accuracy Levels:

The following tables summarize the pins and attributes required to achieve various accuracy levels for the economic KPIs.

High

Components Pins Attributes
Combined heat and power - Start-up costs
Generator nominal power
Boiler - Start-up costs
Nominal heat production
Heat pump - Coefficient of performance
Electricity price
Nominal heat production

Medium

Components Pins Attributes
Boiler - Nominal heat production
Heat pump - Nominal heat production
Combined heat and power - Generator nominal power

If the available attributes and mapped pins are not sufficient enough to reach a "Medium" accuracy for the economic KPIs, no economic KPIs are calculated.

Boiler

Pin Required Mapping info
Operating message Yes -
Attribute Required Mapping info Unit
Nominal heat production No Necessary for Economic KPIs, all accuracy levels. Used to scale "Start-up costs". Default: None kW
Startup costs No Necessary for Economic KPIs, accuracy level "High". Scaled with "Nominal heat production": Default: 0.01 €/kW €/kW

Combined heat and power

Pin Required Mapping info
Operating message Yes -
Attribute Required Mapping info Unit
Generator nominal power No Necessary for Economic KPIs, all accuracy levels. Used to scale "Start-up costs". Default: None kW
Startup costs No Necessary for economic KPIs, accuracy level "High". Scaled with "Generator nominal power": Default: 0.02 €/kW €/kW

Fan

Pin Required Mapping info
Operating message Yes -

Heat pump

Pin Required Mapping info
Operating message Yes -
Attribute Required Mapping info Unit
Coefficient of performance No Necessary for Economic KPIs, accuracy level "High". Default: 4
Nominal heat production No Necessary for Economic KPIs, all accuracy levels. Used to scale "Start-up costs". Default: None kW
Startup costs No Necessary for Economic KPIs, accuracy level "High". Scaled with "Generator nominal power": Default: 0.18 €/kW €/kW

Thermal control loop

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is mandatory. If both pins are mapped, operating message is used
Pump operating message No Mapping of either operating message (preferred) or pump operating message is mandatory. If both pins are mapped, operating message is used

Recommend Time Span

1 day to 1 week


Recommended Repetition

Every month

  • Cycle rates have a strong seasonal effect
  • Frequent repetition allows to identify operational bad points
  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Reduced Load Analysis

The Reduced Load Analysis identifies the presence of a reduced load mode based on temperature setpoints of the system under consideration. The temperature spread of the system is determined. A reduced load mode offers the possibility of operational cost and energy reductions. Additionally, a comparison with a user-defined schedule reveals times when the component could be in a reduced load operating mode.

Value

  • Lower operating costs
  • Lower energy consumption

Recommended for components

Heat and cold distribution systems, energy conversion plants, and indoor areas, such as

  • Heating loops
  • Cooling loops
  • Boilers
  • Office rooms
  • Schooling rooms

Checked conditions

  • Existence of a load reduction period, e.g., night-time temperature reduction for heating
  • Condition checks on times of components operation
  • Estimation of times when the load can be reduced according to a user-defined schedules

This example shows the results of a Reduced Load Analysis performed on a heating circuit.

reduced-load-analysis
Figure 1: Temperature setpoint of the heating circuit
Figure 1 shows the recorded temperature setpoint. The setpoint changes from operation at normal load to reduced load according to the schedule in the table below. The detected temperature level shift corresponds to 10 °C.

Schedule

Day Time
Mon 05:00 - 18:00
Tue 05:00 - 18:00
Wed 05:00 - 18:00
Thu 05:00 - 18:00
Fri 05:00 - 18:00
Sat 07:00 - 14:00
Sun 07:00 - 14:00
KPI Value Unit
reduced load operation Yes binary
temperature level shift 10 °C
operating time 62.4 h
operating time.normal load.reducible 1.77 h
operating time.normal load.reducible.relative 2.84 %
operating time.normal load.scheduled 60.6 h

Signal colors

Signal color Available Info
red Yes No load reduction identified (applied for thermal control loop)
yellow Yes No load reduction identified (applied for any other component than thermal control loop)
green Yes Load reduction identified

Interpretations

Available Info
Yes Either the operational rule checks if the analysis were tested positive or not

Recommendations

Available Info
Yes Implementation hints for load reduction. No recommendation, in case of sufficient measurement quality.

KPIs

Identification of reduced load mode

KPI Identifier Description Value Range Unit
reduced load operation Whether a reduced load mode was detected
No = no reduced load identified
Yes = reduced load identified
Yes, No binary

Statistics of temperature level shift

KPI Identifier Description Value Range Unit
temperature level shift Difference between setpoint temperature levels at the time of load reduction
negative values = reduced temperature level for heating load reduction
positive values = raised temperature level for cooling load reduction
-inf to inf °C

Schedule operating times

KPIs of this category analyse if the load reduction is in accordance to a schedule and if there are further savings by adjusting/implementing a load reduction schedule.

KPI Identifier Description Value Range Unit
operating time Total time of operation 0 to inf h
operating time.normal load.reducible Total time component was operated under normal load outside the reviewed schedule and therefore could be saved 0 to inf h
operating time.normal load.reducible.relative Percentage of reducible operating time under normal load relative to the total operating time 0 to 100 %
operating time.normal load.scheduled Total time of operation under normal load that is scheduled 0 to inf h

Time series

KPI Identifier Description Value Range Unit
normal load.timeseries Timeseries of reduced operating mode
0 = reduced load operation
1 = normal operation
0 or 1 binary

Boiler

Pin Required Mapping info
Outlet temperature setpoint Yes -
Attribute Required Mapping info
Custom day schedules No -
Custom holiday No -
Pre-conditioning period No -
Regional key No -
Schedule No Times for operation at normal load
Schedule timezone No Strongly recommended
Default: UTC
Shutdown flexibility No -

Room

Pin Required Mapping info
Temperature setpoint Yes -
Attribute Required Mapping info
Custom day schedules No -
Custom holiday No -
Pre-conditioning period No -
Regional key No -
Schedule No Times for operation at normal load
Schedule timezone No Strongly recommended
Default: UTC
Shutdown flexibility No -

Thermal control loop

Pin Required Mapping info
Outlet temperature setpoint Yes -
Attribute Required Mapping info
Custom day schedules No -
Custom holiday No -
Pre-conditioning period No -
Regional key No -
Schedule No Times for operation at normal load
Schedule Timezone No Strongly recommended
Default: UTC
Shutdown Flexibility No -

Recommend Time Span

1 day to 1 week


Recommended Repetition

Every 3 months

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Room Air Quality Analysis

The Room Air Quality Analysis checks and interprets the compliance of carbon dioxide concentration in the air to the recommendations of DIN EN 13779: 2007-09. In the case of poor air quality, measures for improvement are recommended. Human performance is significantly influenced by air quality. Furthermore, the algorithm identifies calibration errors by physical plausibility checks.

Value

  • Higher occupant comfort, health and performance

Recommended for components

  • Room

Checked conditions

  • Indoor CO2 concentration evaluation based on DIN EN 13779: 2007-09
  • Identification of higher room ventilation needs
  • Sensor calibration check by plausibility of minimal measured concentration levels
  • Condition checks on times of components operation

The room air quality analysis was applied to an office room with a CO2 sensor and a schedule from 8:00 to 18:00.

rwth-co2-concentration
Figure 1: CO2 concentration and presence

In this scenario, figure 1 shows the time series recorded for a week in July. Air quality is good for at least 60 percent of the office hours. Especially right before lunchtime and in the afternoon, there is room for improvement. If this office is used with 100 people and an average salary of 41 €/hour, better air quality could increase productivity such that we could save approximately 1140 € per week.

KPI Value Unit
co2.maximum 1232 ppm
co2.minimum 399 ppm
co2.mean 672.9 ppm
co2.median 643 h
co2 duration.IDA1.relative 60.7 %
co2 duration.IDA1 42.5 h
co2 duration.IDA2.relative 28.8 %
co2 duration.IDA2 20.2 h
co2 duration.IDA3.relative 10.4 %
co2 duration.IDA3 7.31 h
co2 duration.IDA4.relative 0 %
co2 duration.IDA4 0 h
room air quality salary savings.daily 162.9 €/d
room air quality salary savings.weekly 1140.3 €/d
room air quality productivity gains.relative 0.397 €/d

Signal colors

Signal color Available Info
red Yes CO2 concentrations critical for human health
yellow Yes CO2 concentrations can reduce human comfort, decisiveness, and performance or wrongly calibrated CO2 sensors
green Yes CO2 concentrations sufficient for high comfort

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations to improve fresh air supply, if necessary or to re-calibrate the sensor, if physically implausible measures are observed. No recommendation, in case of sufficient air quality

KPIs

Air Quality Classification

How long was the air quality in the room (based on carbon dioxide concentrations) considered “good”, “medium”, “moderate” or “poor”? Assessments are based on DIN EN 13779 classifications of Indoor Air Quality (IDA) classes 1 (“good”) to 4 (“poor”).

KPI Identifier Description Value Range Unit
co2 duration.IDA1.relative Duration with “good“ indoor air quality 0 to 100 %
co2 duration.IDA2.relative Duration with “medium “ indoor air quality 0 to 100 %
co2 duration.IDA3.relative Duration with “moderate “ indoor air quality 0 to 100 %
co2 duration.IDA4.relative Duration with “poor “ indoor air quality 0 to 100 %
co2 duration.IDA1 Duration with “good“ indoor air quality 0 to inf h
co2 duration.IDA2 Duration with “medium “ indoor air quality 0 to inf h
co2 duration.IDA3 Duration with “moderate “ indoor air quality 0 to inf h
co2 duration.IDA4 Duration with “poor “ indoor air quality 0 to inf h

Statistics of CO2 Concentration

Providing deeper insights into the carbon dioxide concentrations over the analyzed period.

KPI Identifier Description Value Range Unit
co2.maximum Largest CO2 concentrations 0 to inf ppm
co2.minimum Smallest CO2 concentrations 0 to inf ppm
co2.mean Average CO2 concentrations 0 to inf ppm
co2.median Median CO2 concentrations 0 to inf ppm

Economic KPIs

Economic KPIs estimate the economic optimization potentials of the observed operational state. The KPIs indicate the possible productivity gains and the resulting salary savings for adjusting the CO2 content of the room air below 1000 ppm.

The Economic KPIs are provided for the components:

  • Room

Their availability and accuracy depend on the component's mapping. The analysis function always determines the highest possible accuracy.

Accuracy Levels:

High

Components Pins Attributes
Room Presence or Operting message
CO2
Complementary: Room type (used in combination with Presence or Operating message to estimate room usage).

Medium

Components Pins Attributes
Room CO2 Schedule
Complementary:
Custom day schedule
Schedule timezone
Custom holiday
Regional key
Room type (used in combination with schedule attributes to estimate room usage).

Low

Components Pins Attributes
Room CO2
Assumption of 24/7 usage
Complementary: Room type (used to estimate room usage).

All Accuracy Levels

Components Pins Attributes
Room - Average salary
Maximum occupation of the room

Salary savings KPIs

KPI Identifier Description Value Range Unit
room air quality salary savings.daily Identified salary savings potential from employee productivity losses due to CO2 content in the room air above 1000 ppm. The savings are provided as average daily savings potential. 0 to inf €/d
room air quality salary savings.weekly Identified salary savings potential from employee productivity losses due to CO2 content in the room air above 1000 ppm. The savings are provided as average weekly savings potential if the analyzed period is at least one week long. 0 to inf €/week

Productivity gains KPI

KPI Identifier Description Value Range Unit
room air quality productivity gains.relative Identified percentual productivity gains for reducing the CO2 content in the room air to values below 1000 ppm. 0 to 100 %

Room

Pin Required Mapping info Unit
CO2 Yes Necessary for Economic KPIs, all accuracy levels. ppm
Operating message No Used for Economic KPIs, accuracy level "High". It is used subordinate to pin "presence". Default: Always presence binary
Presence No Used for Economic KPIs, accuracy level "High". It is preferred over pin "operating message".
Default: Always presence
binary
Attribute Required Mapping info Unit
Average salary No Necessary for Salary KPIs of Economic KPIs, all accuracy levels. €/person
Occupation max No Necessary for Salary KPIs of Economic KPIs, all accuracy levels. -
Room type No Available values:
- 24/7 full occupancy
- classroom
- single person office multi persons office
- store
- restaurant
- conference room
- kindergarten
Default: 24/7 full occupancy
-
Schedule timezone No Default: UTC -
Custom day schedules No Default: None -
Regional key No Default: None -
Schedule No Default: None -

Recommend Time Span

1 day to 1 week

  • Utilize on days with room occupation

Recommended Repetition

Every month

  • After changes of room occupation or usage
  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system of the ventilation systems
  • After maintenance or replacements in ventilation systems

Schedule Analysis

The Schedule Analysis is used to compare the actual occurred switch on/switch off times of the component with a schedule/timetable stored inside analytics. This analysis aims at identifying the number of hours the component is active outside of the scheduled times. In addition to a one-time check, the analysis is suitable for permanent checks, e.g., to identify manual overwriting of the operating schedule. The analysis considers holidays and customized schedules.

Value

  • Lower operating times of HVAC components
  • Lower energy consumption
  • Lower maintenance costs due to less component operating time

Recommended for components

Any HVAC component or room whose usage follows a recurrent schedule, such as:

  • Fans
  • Thermal control loops
  • Office rooms
  • Sales rooms

Checked conditions

  • Component operation outside a user-defined schedule
  • Component operation during a user-defined schedule
  • Condition checks on times of components operation

This example shows a Schedule Analysis for a component "fan" connected to a supply fan operating message of an HVAC machine. The switch on/off times of the machine are shown as a blue line in figure 1, blue regions in the background correspond to the expected schedule.

schedule-analysis
Figure 1: Operating times of component and reference schedule

A reduction of ~9% of the total operating time is possible, as can be seen in the table of KPIs below. With the help of the plot we can also see, that the times where we can reduce the operating time are distributed over the workdays of the week. Furthermore, the mapping of the component enables the determination of economic KPIs with a "low" accuracy level. Assuming a nominal power consumption of 3 kW and the electricity price to be 0.18 €/kWh, the energy costs outside the scheduled operating times are calculated. This results in weekly energy costs of 3.75 € which fall outside of the schedule.

KPI Value Unit
operating time 74 h
operating time.reducible 6.94 h
operating time.reducible.relative 9.38 %
operating time.scheduled 67.1 h
savings.daily 1.53 €/d
energy consumption costs.outside schedule.daily 0.54 €/day
energy consumption costs.outside schedule.weekly 3.75 €/week

Signal colors

Signal color Available Info
red Yes Significant operation times outside of the parameterized schedule identified
yellow Yes Partial operation times outside of the parameterized schedule identified
green Yes Sufficient operation according to the parameterized schedule

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations to improve the scheduled operation of the component. No recommendation, in case of sufficient measurement quality

KPIs

Operating Time and Schedule

KPI Identifier Description Value Range Unit
operating time Total time of operation 0 to inf h
operating time.reducible Total time component was operated outside the reviewed schedule and therefore could be saved 0 to inf h
operating time.reducible.relative Percentage of reducible time relative to the total operating time 0 to 100 %
operating time.scheduled Total time of operation during schedule 0 to inf h

Economic KPIs

Economic KPIs estimate the economic optimization potentials of the observed operational state. The KPIs indicate the energy costs outside of scheduled operating or usage times of the investigated component.

KPI Identifier Description Value Range Unit
energy consumption costs.outside schedule.daily Identified energy consumption costs outside of scheduled operating time. The costs are provided as average daily costs. 0 to inf €/day
energy consumption costs.outside schedule.weekly Identified energy consumption costs outside of scheduled operating time. The costs are provided as average weekly costs. This KPI is provided if the analyzed time span is at least one week long. 0 to inf €/week

The Economic KPIs are provided for the components:

  • Boiler
  • Combined heat and power
  • Fan
  • Heat pump

Their availability and accuracy depend on the component's mapping. The analysis function always determines the highest possible accuracy.

Accuracy Levels:

The following tables summarize the pins and attributes required to achieve various accuracy levels for the economic KPIs.

High

Components Pins Attributes
Boiler Rate of fuel consumption Fuel price
Combined heat and power Rate of fuel consumption Fuel price
Fan Electrical power Electricity price
Heat pump Electrical power Electricity price

Medium

Components Pins Attributes
Boiler Heat flow Efficiency
Fuel price
Combined heat and power Generator power
Heat flow
Fuel price
Fuel utilization factor
Fan Speed Electricity price
Nominal power consumption
Heat pump Heat flow Coefficient of performance
Electricity price

Low

Components Pins Attributes
Fan - Electricity price
Nominal power consumption
Heat pump - Coefficient of performance
Electricity price
Nominal heat production
Boiler - Efficiency
Fuel price
Nominal heat production
Combined heat and power - Fuel price
Fuel utilization factor
Generator nominal power
Nominal heat production

If the available attributes and mapped pins are not sufficient enough to reach a "Low" accuracy for the economic KPIs, see "operating time.reducible.relative for a rough estimation.

Boiler

Pin Required Mapping info Unit
Rate of fuel consumption No Necessary for economic KPIs, accuracy level "High". kW
Heat flow No Necessary for economic KPIs, accuracy level "Medium". kW
Operating message Yes - -
Attribute Required Mapping info Unit
Custom day schedules No - -
Custom holiday No - -
Efficiency No Necessary for economic KPIs, accuracy levels "Medium" and "Low". Default: 0.915 -
Fuel price No Necessary for economic KPIs, all accuracy levels. Default: 0.06 €/kWh €/kWh
Nominal heat production No Necessary for economic KPIs, accuracy level "Low". Default: None kW
Pre-conditioning period No - min
Regional key No - -
Schedule Yes - -
Schedule timezone No Strongly recommended Default: UTC -
Shutdown flexibility No - min

Combined heat and power

Pin Required Mapping info Unit
Fuel power No Necessary fo economic KPIs, accuracy level "High" kW
Generator power No Necessary for economic KPIs, accuracy level "Medium" kW
Heat flow No Necessary for economic KPIs, accuracy level "Medium" kW
Operating message Yes - -
Attribute Required Mapping info Unit
Custom day schedules No - -
Custom holiday No - -
Fuel price No Necessary for economic KPIs, all accuracy levels. Default: 0.06 €/kWh €/kWh
Fuel utilization factor No Necessary for economic KPIs, accuracy levels "Medium" and "Low". Default: 0.87 -
Generator nominal power No Necessary for economic KPIs, accuracy level "Low". Default: None kW
Nominal heat production No Necessary for economic KPIs, accuracy level "Low". Default: None kW
Pre-conditioning period No - min
Regionalkey No - -
Schedule Yes - -
Schedule timezone No Strongly recommended Default: UTC -
Shutdown flexibility No - min

Fan

Pin Required Mapping info Unit
Electrical power No Necessary for economic KPIs, accuracy level "High" kW
Speed No Necessary for economic KPIs, accuracy level "Medium" %
Operating message Yes -
Attribute Required Mapping info Unit
Custom day schedules No - -
Custom holiday No - -
Electricity price No Necessary for Economic KPIs, all accuracy levels. Default: 0.18 €/kWh €/kWh
Nominal power consumption No Necessary for Economic KPIs, accuracy levels "Medium" and "Low". Default: None kW
Pre-conditioning period No - min
Regional key No - -
Schedule Yes - -
Schedule timezone No Strongly recommended Default: UTC -
Shutdown flexibility No - min

Heat pump

Pin Required Mapping info Unit
Condenser heat flow No Necessary for economic KPIs, accuracy level "Medium". kW
Electrical power No Necessary for economic KPIs, accuracy level "High". kW
Operating message Yes - -
Attribute Required Mapping info Unit
Custom day schedules No - -
Custom holiday No - -
Electricity price No Necessary for economic KPIs, all accuracy levels. Default: 0.18 €/kWh €/kWh
Nominal heat production No Necessary for economic KPIs, accuracy level "Low". Default: None kW
Pre-conditioning period No - min
Regional key No - -
Schedule Yes - -
Schedule timezone No Strongly recommended Default: UTC -
Shutdown flexibility No - min

Thermal control loop

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is mandatory. If both pins are mapped, operating message is used
Pump operating message No Mapping of either operating message (preferred) or pump operating message is mandatory. If both pins are mapped, operating message is used
Attribute Required Mapping info Unit
Custom day schedules No - -
Custom holiday No - -
Pre-conditioning period No - min
Regional key No - -
Schedule Yes - -
Schedule timezone No Strongly recommended
Default: UTC
-
Shutdown flexibility No - min

Room

Applying a schedule analysis on rooms is recommended to check for a scheduled room control operation. Utilize the reduced load analysis if a scheduled load reduction of heating or cooling utilities shall be analyzed.

Pin Required Mapping info
Operating message Yes -
Attribute Required Mapping info Unit
Custom day schedules No - -
Custom holiday No - -
Pre-conditioning period No - min
Regional key No - -
Schedule Yes - -
Schedule timezone No Strongly recommended
Default: UTC
-
Shutdown flexibility No - min

Recommend Time Span

1 week


Recommended Repetition

Every week

  • After adjustment of usage times of the analyzed component
  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Sensor Outage Analysis

The Sensor Outage Analysis uses the time series data of the sensor to detect irregularities of observations. This implies manual overwriting of the sensor values, constant observations for expected volatile trajectories of the data points' observations, and also value plausibility checks by types of sensors.

Value

  • Confirm normal operation of sensors
  • Identify faulty measurement setups inside your building automation system
  • Detection of permanently manual overwritten sensors causing permanent manipulation of control loop

Recommended for components

Any component with sensors measuring physical quantities.


Checked conditions

  • Measurements of a sensor lie within a reasonable range
  • Detects constant observation for sensors which expect volatile trajectories

For this example we are looking at a temperature sensor for the room air temperature, that is connected to a component "room". The KPIs are generated according to the mapped pins. For this setup we mapped a datapoint to pin pin "temperature", thus the result contains the three KPIs listed below.

The room temperature is measured by the sensor with values above the plausibility limit of 40 °C. The KPI "pin.temperature.above high limit = 1" indicates that the measured values do not lie within a reasonable range for room temperatures.

If any of the KPIs have the boolean value of 1, a faulty sensor is detected and the signal color red is returned to alarm. A detected fault can be caused by various reasons ranging from manually overwritten sensors over a faulty sensor to a wrong configured measurement system.

sensor-outage-analysis
Figure 1: Room air temperature over a two day period

KPI Value Unit
pin.temperature.below low limit No binary
pin.temperature.above high limit Yes binary
pin.temperature.faulty No binary

Signal colors

Signal color Available Info
red Yes One or more Sensors have to be checked
yellow No -
green Yes No faulty sensors detected

Interpretations

Available Info
Yes Detection of faulty sensors or plausible observations

Recommendations

Available Info
Yes Recommendations to correct the reason for the sensor fault

KPIs

PIN_NAME refers to the actual pin on the component that the KPI belongs to.

KPI Identifier Description Value Range Unit
pin.<PIN NAME>.datatype Indicator of Pin datatype analog, digital -
pin.<PIN NAME>.below low limit Time Series values of pin "PIN_NAME" below low limit
0 = observations in plausible range
1 = observations below lowest plausible value detected
Yes, No binary
pin.<PIN NAME>.above high limit Time Series values of pin "PIN_NAME" above high limit
0 = observations in plausible range
1 = observations above highest plausible value detected
Yes, No binary

Sensor Fault

KPI Identifier Description Value Range Unit
pin.<PIN NAME>.faulty Sensor of pin "PIN_NAME" below low limit Yes, No binary

Additional KPIs for Digital Pins

KPI Identifier Description Value Range Unit
pin.<PIN NAME>.contains not allowed values Indicator if time series on pin contains only values of 0 or 1 Yes, No binary

Air cooler

Pin Required Mapping info
Cooling energy - water side No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Cooling power - water side No Checked for faults
datatype: analog
low limit = 0
high limit not set
Inlet air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Operating message No Not checked for faults
datatype: digital
no limit defined
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Outlet air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Pump operating message No Not checked for faults
datatype: digital
no limit defined
Return temperature - water side No Checked for faults
datatype: analog
low limit = -10
high limit = 100
Supply temperature - water side No Checked for faults
datatype: analog
low limit = -10
high limit = 100
Valve control signal No Not checked for faults
datatype: analog
no limit defined
Valve position No Not checked for faults
datatype: analog
low limit = 0
high limit = 100
Volume flow - water side No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Air heater

Pin Required Mapping info
Heating energy - water side No Checked for faults
datatype: analog
low limit = 0
high limit not set
Heating power - water side No Checked for faults
datatype: analog
low limit = 0
high limit not set
Inlet air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Operating message No Not checked for faults
datatype: digital
no limit defined
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Outlet air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Pump operating message No Not checked for faults
datatype: digital
no limit defined
Return temperature - water side No Checked for faults
datatype: analog
low limit = -10
high limit = 100
Supply temperature - water side No Checked for faults
datatype: analog
low limit = -10
high limit = 100
Valve control signal No Not checked for faults
datatype: analog
no limit defined
Valve position No Not checked for faults
datatype: analog
low limit = 0
high limit = 100
Volume flow - water side No Checked for faults
datatype: analog
low limit = 0
high limit not set

Boiler

Pin Required Mapping info
Alarm message No Not checked for faults
datatype: digital
no limit defined
Heating energy No Checked for faults
datatype: analog
no limit defined
Heating power No Checked for faults
datatype: analog
no limit defined
Operating message No Not checked for faults
datatype: digital
no limit defined
Return temperature No Checked for faults
datatype: analog
low limit = 1
high limit = 100
Supply temperature No Checked for faults
datatype: analog
low limit = 1
high limit = 100
Supply temperature setpoint No Not checked for faults
datatype: analog
no limit defined
Volume flow No Not checked for faults
datatype: analog
no limit defined

Combined heat and power

Pin Required Mapping info
Alarm message No Not checked for faults
datatype: digital
no limit defined
Heating energy No Checked for faults
datatype: analog
no limit defined
Heating power No Checked for faults
datatype: analog
no limit defined
Operating message No Not checked for faults
datatype: digital
no limit defined
Return temperature No Checked for faults
datatype: analog
low limit = 1
high limit = 100
Supply temperature No Checked for faults
datatype: analog
low limit = 1
high limit = 100
Supply temperature setpoint No Not checked for faults
datatype: analog
no limit defined
Volume flow No Not checked for faults
datatype: analog
no limit defined

Compression chiller

Pin Required Mapping info
Alarm message No Not checked for faults
datatype: digital
no limit defined
Cooling energy evaporator No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Cooling power evaporator No Checked for faults
datatype: analog
low limit = 0
high limit not set
Electrical power No Checked for faults
datatype: analog
low limit = 0
high limit not set
Inlet temperature condenser No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Inlet temperature evaporator No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Operating hours No Checked for faults
datatype: analog
low limit = 0
high limit not set
Operating message No Not checked for faults
datatype: digital
no limit defined
Operating message pump - condenser No Not checked for faults
datatype: digital
no limit defined
Operating message pump - evaporator No Not checked for faults
datatype: digital
no limit defined
Operating starts No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Outlet temperature condenser No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Outlet temperature evaporator No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Outlet temperature setpoint - condenser No Not checked for faults
datatype: analog
no limit defined
Outlet temperature setpoint - evaporator No Not checked for faults
datatype: analog
no limit defined
Volume flow evaporator No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Cooling circuit

Pin Required Mapping info
Cooling energy No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Cooling power No Checked for faults
datatype: analog
low limit = 0
high limit not set
Operating message No Not checked for faults
datatype: digital
no limit defined
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Pump operating message No Not checked for faults
datatype: digital
no limit defined
Return temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Supply temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Supply temperature setpoint No Not checked for faults
datatype: analog
no limit defined
Valve control signal No Not checked for faults
datatype: analog
no limit defined
Valve position No Not checked for faults
datatype: analog
low limit = 0
high limit = 100
Volume flow No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Electricity meter

Pin Required Mapping info
Active energy No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Active power No Checked for faults
datatype: analog
low limit = 0
high limit not set
Reactive energy No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Reactive power No Checked for faults
datatype: analog
low limit = 0
high limit not set

Fan

Pin Required Mapping info
Alarm message No Not checked for faults
datatype: digital
no limit defined
Operating message No Not checked for faults
datatype: digital
no limit defined
Speed No Not checked for faults
datatype: analog
low limit = 0
high limit = 100

Filter

Pin Required Mapping info
Filter contamination No Not checked for faults
datatype: analog
no limit defined
Pressure difference No Checked for faults
datatype: analog
low limit = 0
high limit not set

Gas meter

Pin Required Mapping info
Gas quantity No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Volume flow No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Heat meter

Pin Required Mapping info
Heating energy No Checked for faults
datatype: analog
no limit defined
Heating power No Checked for faults
datatype: analog
no limit defined
Return temperature No Checked for faults
datatype: analog
low limit = 1
high limit = 100
Supply temperature No Checked for faults
datatype: analog
low limit = 1
high limit = 100
Volume flow No Not checked for faults
datatype: analog
no limit defined

Heat pump

Pin Required Mapping info
Alarm message No Not checked for faults
datatype: digital
no limit defined
Electrical power No Checked for faults
datatype: analog
no limit defined
Heating energy condenser No Checked for faults
datatype: analog
no limit defined
Heating energy evaporator No Checked for faults
datatype: analog
no limit defined
Heating power condenser No Checked for faults
datatype: analog
no limit defined
Heating power evaporator No Checked for faults
datatype: analog
no limit defined
Inlet temperature condenser No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Inlet temperature evaporator No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Operating message No Not checked for faults
datatype: digital
no limit defined
Operating message pump - condenser No Not checked for faults
datatype: digital
no limit defined
Operating message pump - evaporator No Not checked for faults
datatype: digital
no limit defined
Outlet temperature condenser No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Outlet temperature evaporator No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Outlet temperature setpoint - condenser No Not checked for faults
datatype: analog
no limit defined
Outlet temperature setpoint - evaporator No Not checked for faults
datatype: analog
no limit defined
Volume flow condenser No Not checked for faults
datatype: analog
no limit defined
Volume flow evaporator No Not checked for faults
datatype: analog
no limit defined

Heat transfer unit

Pin Required Mapping info
Heating energy - primary No Checked for faults
datatype: analog
low limit = 0
high limit not set
Heating power - primary No Checked for faults
datatype: analog
low limit = 0
high limit not set
Operating message No Not checked for faults
datatype: digital
no limit defined
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Pump operating message - secondary No Not checked for faults
datatype: digital
no limit defined
Return temperature - primary No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Return temperature - secondary No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Supply temperature - primary No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Supply temperature - secondary No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Supply temperature setpoint - secondary No Not checked for faults
datatype: analog
no limit defined
Valve control signal - primary No Not checked for faults
datatype: analog
no limit defined
Valve position - primary No Not checked for faults
datatype: analog
low limit = 0
high limit = 100
Volume flow - primary No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Heating circuit

Pin Required Mapping info
Heating energy No Checked for faults
datatype: analog
no limit defined
Heating power No Checked for faults
datatype: analog
no limit defined
Operating message No Not checked for faults
datatype: digital
no limit defined
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Pump operating message No Not checked for faults
datatype: digital
no limit defined
Return temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Supply temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Supply temperature setpoint No Not checked for faults
datatype: analog
no limit defined
Valve control signal No Not checked for faults
datatype: analog
no limit defined
Valve position No Not checked for faults
datatype: analog
low limit = 0
high limit = 100
Volume flow No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Humidity conditioner

Pin Required Mapping info
Operating message No Not checked for faults
datatype: digital
no limit defined
Outside air relative humidity No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Outside air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Supply air relative humidity No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Supply air temperature No Checked for faults
datatype: analog
low limit = -20
high limit = 80

Recooling plant

Pin Required Mapping info
Cooling energy No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Cooling power No Checked for faults
datatype: analog
low limit = 0
high limit not set
Electrical energy No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Electrical power No Checked for faults
datatype: analog
low limit = 0
high limit not set
Operating message No Not checked for faults
datatype: digital
no limit defined
Operating message fan No Not checked for faults
datatype: digital
no limit defined
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Return temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Speed No Not checked for faults
datatype: analog
no limit defined
Supply temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Volume flow No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Water quantity No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Room

Pin Required Mapping info
CO2 No Not checked for faults
datatype: analog
low limit = 300
high limit not set
Dew point alarm message No Not checked for faults
datatype: digital
no limit defined
Operating message No Not checked for faults
datatype: digital
no limit defined
Outside air temperature No Checked for faults
datatype: analog
no limit defined
Presence No Not checked for faults
datatype: analog
no limit defined
Relative humidity No Checked for faults
datatype: analog
no limit defined
Temperature No Checked for faults
datatype: analog
low limit = 5
high limit = 40
Temperature setpoint No Not checked for faults
datatype: analog
no limit defined

Thermal control loop

Pin Required Mapping info
Alarm message No Not checked for faults
datatype: digital
no limit defined
Inlet temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Inlet temperature recirculation No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Operating message No Not checked for faults
datatype: digital
no limit defined
Outlet temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 100
Outlet temperature setpoint No Not checked for faults
datatype: analog
no limit defined
Pump operating message No Not checked for faults
datatype: digital
no limit defined
Valve control signal No Not checked for faults
datatype: analog
no limit defined
Valve position No Not checked for faults
datatype: analog
low limit = 0
high limit = 100

Thermal energy storage

Pin Required Mapping info
Lower storage temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Outdoor air temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50
Pump operating message - primary No Not checked for faults
datatype: digital
no limit defined
Pump operating message - secondary No Not checked for faults
datatype: digital
no limit defined
Upper storage temperature No Checked for faults
datatype: analog
low limit = 0
high limit = 100

Water meter

Pin Required Mapping info
Volume flow No Not checked for faults
datatype: analog
low limit = 0
high limit not set
Water quantity No Not checked for faults
datatype: analog
low limit = 0
high limit not set

Weather station

Pin Required Mapping info
Reference relative humidity No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Reference temperature No Checked for faults
datatype: analog
no limit defined
Relative humidity No Checked for faults
datatype: analog
low limit = 0
high limit = 100
Temperature No Checked for faults
datatype: analog
low limit = -50
high limit = 50

Recommend Time Span

1 week - several weeks


Recommended Repetition

Every week

  • A sensor fault can occur at any moment

Setpoint Deviation Analysis

The Setpoint Deviation Analysis identifies setpoints that are not met by their process values. The difference between the setpoint and the actual value is also known as the setpoint deviation. A high setpoint deviation is a symptom that can be traced back to many different causes. E.g., the insufficient supply of a controlled system with the required temperature level, suboptimal controller software, and parameters, or a blocked valve. The Setpoint Deviation Analysis incorporates features that help to narrow down the root cause of a high setpoint deviation, such as setpoint deviations caused by upstream components.

Value

Setpoint deviation is a strong symptom for faulty control loop operation, e.g., caused by

  • Technical defects in the control loop supply,
  • Control loop malfunctions, and
  • Faulty control loop parameter settings.

Benefits of improving insufficient setpoint value attainment are

  • Higher occupant comfort, health, and performance
  • Lower operating costs
  • Higher energy efficiency

Recommended for components

Control loops, such as

  • Heating systems
  • Ventilation systems
  • Air-conditioning systems

Checked conditions

  • Setpoint deviation
  • Setpoint value is has been manually overridden
  • Upstream components do not have the required temperature levels to meet the setpoint

In this example, a thermal control loop is assessed for a week (see Figure 1). Throughout the week, there is a high setpoint deviation, indicating that there is a problem with the thermal control loop.

setpoint-deviation-analysis
Figure 1: Example of a process value (actual value) undershooting its setpoint

Recommendations are given to check the thermal control loop to find possible causes of the high setpoint deviation.

KPI Value Unit
operating time 164.7 h
operating time.relative 98.0 %
setpoint deviation tolerance 1.5 °C
outlet temperature setpoint deviation.duration.greater than threshold 164.7 h
outlet temperature setpoint deviation.duration.greater than threshold.relative 100.0 %
outlet temperature.actual value above setpoint.maximum 0.0 °C
outlet temperature.actual value above setpoint.mean 0.0 °C
outlet temperature.actual value below setpoint.maximum 44.0 °C
outlet temperature.actual value below setpoint.mean 29.6 °C

Signal colors

Signal color Available Info
red No The analysis identifies the symptom and recommends measures to investigate the root cause of the setpoint deviation. Red as a signal for a low cost measure with high impact on the building operation will not be provided.
yellow Yes Setpoint deviation is a strong symptom for suboptimal control and system performance. Investing the extra effort to identify the root cause and fixing it is strongly recommended.
green Yes Sufficient setpoint compliance in respect to usual tolerances in buildings

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations on how to investigate the root cause of a setpoint deviation. No recommendation, if setpoint compliance is sufficient

KPIs

<setpoint> refers to the setpoint type.

The available setpoint types are:

  • co2
  • condenser/evaporator outlet temperature (for heat pumps and compression chillers)
  • outlet temperature
  • pressure difference
  • temperature

Operating Time

Operating time KPIs provide information on the total time of operation of the analyzed component during the analyzed time frame.

KPI Identifier Description Value Range Unit
operating time Total operating time 0 to inf h
operating time.relative Relative operating time 0 to 100 %

Incidence of Setpoint Deviation

Duration and statistics of the setpoint deviations, for deviations greater than the setpoint deviation tolerance.

KPI Identifier Description Value Range Unit
setpoint deviation tolerance The setpoint deviation which is considered acceptable 0 to inf unit of setpoint
<setpoint> deviation.duration.greater than threshold Total time for which the setpoint deviation is greater than the threshold for setpoint deviation. 0 to inf h
<setpoint> deviation.duration.greater than threshold.relative Total time for which the setpoint deviation is greater than the threshold for setpoint deviation, relative to total operating time. 0 to 100 %
<setpoint>.actual value above setpoint.maximum Largest setpoint deviation where process values is greater than setpoint. 0 to inf unit of setpoint
<setpoint> .actual value above setpoint.mean Average setpoint deviation where process values is greater than the setpoint. 0 to inf unit of setpoint
<setpoint> .actual value below setpoint.maximum Largest setpoint deviation where process values is smaller than setpoint. 0 to inf unit of setpoint
<setpoint> .actual value below setpoint.mean Average setpoint deviation where process values is smaller than setpoint. 0 to inf unit of setpoint

Upstream component check

KPIs regarding the upstream components.

KPI Identifier Description Value Range Unit
<setpoint>.duration.above inlet Total time for which the outlet setpoint is above the inlets. 0 to inf unit of setpoint
<setpoint>.duration.above inlet.relative Total time for which the outlet setpoint is above the inlets, relative to total operating time. 0 to inf unit of setpoint
<setpoint>.duration.below inlet Total time for which the outlet setpoint is below the inlets. 0 to inf unit of setpoint
<setpoint>.duration.below inlet.relative Total time for which the outlet setpoint is below the inlets, relative to the total operating time. 0 to inf unit of setpoint

Air cooler

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Pump operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Valve control signal Yes -
Valve position Yes -
Attribute Required Mapping info Unit
Valve position setpoint deviation tolerance No Default: 10 % %

Air heater

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Pump operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Valve control signal Yes -
Valve position Yes -
Attribute Required Mapping info Unit
Valve position setpoint deviation tolerance No Default: 10 % %

Boiler

Pin Required Mapping info
Operating message No Mapping strongly recommended
Default: Always operating
Supply temperature Yes -
Supply temperature setpoint Yes -
Attribute Required Mapping info Unit
Temperature setpoint deviation tolerance No Default: 1.5°C °C

Combined heat and power

Pin Required Mapping info
Operating message No Mapping strongly recommended Default: Always operating
Supply temperature Yes -
Supply temperature setpoint Yes -
Attribute Required Mapping info Unit
Temperature setpoint deviation tolerance No Default: 1.5°C °C

Compression chiller

Pin Required Mapping info
Operating message No Mapping strongly recommended
Default: Always operating
Outlet temperature condenser No Required, if condenser shall be analyzed
Outlet temperature evaporator No Required, if evaporator shall be analyzed
Outlet temperature setpoint - condenser No Required, if condenser shall be analyzed
Outlet temperature setpoint - evaporator No Required, if evaporator shall be analyzed
Attribute Required Mapping info Unit
Outlet temperature setpoint deviation tolerance - condenser No Default: 1.5°C
Outlet temperature setpoint deviation tolerance - evaporator No Default: 1.5°C

Cooling circuit

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Pump operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Supply temperature No Required, if supply temperature shall be analyzed
Supply temperature setpoint No Required, if supply temperature shall be analyzed
Valve control signal No Required, if valve position shall be analyzed
Valve position No Required, if valve position shall be analyzed
Attribute Required Mapping info Unit
Supply temperature setpoint deviation tolerance No Default: 1.5°C °C
Valve position setpoint deviation tolerance No Default: 10 % %

Fan

Pin Required Mapping info
Operating message No Mapping strongly recommended
Default: Always operating
Pressure difference Yes -
Pressure difference setpoint Yes -
Attribute Required Mapping info Unit
Pressure difference setpoint deviation tolerance No Default: 20 Pa Pa

Heat pump

Pin Required Mapping info
Operating message No Mapping strongly recommended
Default: Always operating
Outlet temperature condenser No Required, if condenser shall be analyzed
Outlet temperature evaporator No Required, if evaporator shall be analyzed
Outlet temperature setpoint - condenser No Required, if condenser shall be analyzed
Outlet temperature setpoint - evaporator No Required, if evaporator shall be analyzed
Attribute Required Mapping info Unit
Outlet temperature setpoint deviation tolerance - condenser No Default: 1.5°C
Outlet temperature setpoint deviation tolerance - evaporator No Default: 1.5°C

Heat transfer unit

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Pump operating message - secondary No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Supply temperature - secondary No Required, if supply temperature shall be analyzed
Supply temperature setpoint - secondary No Required, if supply temperature shall be analyzed
Valve control signal - primary No Required, if valve position shall be analyzed
Valve position - primary No Required, if valve position shall be analyzed
Attribute Required Mapping info Unit
Supply temperature setpoint deviation tolerance - secondary No Default: 1.5°C °C
Valve position setpoint deviation tolerance - primary No Default: 10 % %

Heating circuit

Pin Required Mapping info
Operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Pump operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Supply temperature No Required, if supply temperature shall be analyzed
Supply temperature setpoint No Required, if supply temperature shall be analyzed
Valve control signal No Required, if valve position shall be analyzed
Valve position No Required, if valve position shall be analyzed
Attribute Required Mapping info Unit
Supply temperature setpoint deviation tolerance No Default: 1.5°C °C
Valve position setpoint deviation tolerance No Default: 10 % %

Room

Pin Required Mapping info
Operating message No Mapping strongly recommended
Default: Always operating
Temperature Yes -
Temperature setpoint Yes -
Attribute Required Mapping info Unit
CO2 setpoint deviation tolerance No Default: 150 ppm ppm
Temperature setpoint deviation tolerance No Default: 2.5°C °C

Thermal control loop

Pin Required Mapping info
Inlet temperature No -
Operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Outlet temperature No Required, if outlet temperature shall be analyzed
Outlet temperature setpoint No Required, if outlet temperature shall be analyzed
Pump operating message No Mapping of either operating message (preferred) or pump operating message is strongly recommended. If operating message and pump operating message are mapped, operating message will be used Default: Always operating
Valve control signal No Required, if valve position shall be analyzed
Valve position No Required, if valve position shall be analyzed
Attribute Required Mapping info Unit
Outlet temperature setpoint deviation tolerance No Default: 1.5°C °C
Valve position setpoint deviation tolerance No Default: 10 % %

Recommend Time Span

1 day to 1 week


Recommended Repetition

Every week

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Setpoint Plausibility Analysis

The Setpoint Plausibility Analysis identifies implausible setpoint values for common application of a component. This is achieved by identifying periods for which the setpoints falls outside of predefined limits.

Value

  • Increase efficiency through better operation
  • Improve occupant comfort

Recommended for components

  • Rooms

Checked conditions

  • Comparison between actual setpoint and typical setpoint for application

In this example, the temperature setpoint of a room changes from 21°C to 16°C (see Figure 1). Since 16°C is below the recommended temperature for rooms, the analysis is evaluated with the signal color "yellow".

setpoint-plausibility-analysis
Figure 1: Temperature setpoint of a room for the period of a week.

The reason for a lower limit of temperature setpoints within rooms is that thermal comfort is reduced and the likelihood of condensation and mold forming increases with low room temperatures. Recommendations are made to reset the setpoint to fall within typical setpoint limits for a room to improve operation and thermal comfort.

KPI Value Unit
operating time 70.0 h
operating time.relative 41.7 %
temperature setpoint.above upper setpoint limit.duration 0.0 h
temperature setpoint.above upper setpoint limit.duration.relative 0.0 %
temperature setpoint.below lower setpoint limit.duration 50.0 h
temperature setpoint.below lower setpoint limit.duration.relative 71.4 %

Signal colors

Signal color Available Info
red No -
yellow Yes Setpoint is outside of the range of setpoints typical for this component for a significant amount of the time.
green Yes Setpoint is within typical limits for this component.

Interpretations

Available Info
Yes Either the operational rule checks of the analysis were tested positive or not.

Recommendations

Available Info
Yes Recommendations to reset the setpoint so that it falls within the expected range for the component.

KPIs

<setpoint> refers to the setpoint type. The available setpoint types are "co2" and "temperature".

KPI Identifier Description Value Range Unit
operating time Total operating time. 0 to inf h
operating time.relative Relative operating time. 0 to 100 %
<setpoint>.above upper setpoint limit.duration Total time for which the setpoint is above the upper setpoint limit. 0 to inf h
<setpoint>.above upper setpoint limit.duration.relative Total time for which the setpoint is above the upper setpoint limit, relative to the total operating time. 0 to 100 %
<setpoint>.below lower setpoint limit.duration Total time for which the setpoint is below the lower limit. 0 to inf h
<setpoint>.below lower setpoint limit.duration.relative Total time for which the setpoint is below the lower limit, relative to the total operating time. 0 to 100 %

Room

Pin Required Mapping info
CO2 setpoint No -
Temperature setpoint No -
Operating message No Mapping strongly recommended
Default: Always operating

Recommend Time Span

1 day to 1 week


Recommended Repetition

Every week

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Synchronized Operation Analysis

The Synchronized Operation Analysis detects whether the operation of the analyzed components is synchronized correctly. E.g., the pump of a thermal control loop is operating while the 2-way valve is closed or rather almost closed. If pumps continue to be operated with the valve closed, this leads to unnecessary power consumption and higher wear of the pump due to the additional running time. A valve opening of 10 % or less is considered as closed.

Value

  • Reduce energy cost
  • Increase lifespan of pumps in heating and cooling circuits
  • Check the interaction between system and pump during switch operations of the system

Recommended for components

Any fluid supply system using, such as

  • Thermal control loop with 2-way valve and pump
  • Thermal control loop with a 3-way valve and pump#
  • Boiler with pump
  • Combined heat and power unit with pump
  • Heat pump with evaporator/condenser feeding pumps

Checked conditions

  • Pump is shutdown, if the two-way valve is closed
  • Pump is still operating although the two-way valve is closed
  • Condition checks on times of components operation

For this example, we use a heating circuit with a 2-way-valve.

Figure 1 shows the pump operating message and valve position of a thermal control loop. During the analysis period, the valve position lies between 0 and 20 %. With the KPI pump operating time.valve closed.relative we can estimate that the valve is nearly closed for ~40 % of the operating time.

valve-pump-relation-analysis
Figure 1: Valve position and pump operating message

KPI Value Unit
pump operating time.valve closed.relative 39.7 %
pump operating time.valve closed 76.2 h
pump operating time.relative 100 %

Signal colors

Signal color Available Info
red Yes Significant pump operation times although 2-way valve was identified as closed
yellow Yes Partial operation times outside of the parameterized schedule identified
green Yes Sufficient operation according to the parameterized schedule

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations to improve the synchronized operation of components. No recommendation, if components are synchronized correctly.

KPIs

KPI Identifier Description Value Range Unit
pump operating time.valve closed.relative Percentage of time the pump is active while the 2-way valve is nearly closed based on total operating time 0 to 100 %
pump operating time.valve closed The amount of time the pump is active while the 2-way valve is nearly closed 0 to inf h
pump operating time.relative Percentage of time the pump is active based on the whole analysis period 0 to 100 %
pump operating time Time the pump is active based on the whole analysis period 0 to inf h

Air cooler

Attribute "Valve type" set to "2-way valve" or "3-way valve"

Pin Required Mapping info
Operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Pump operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Valve position No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.
Valve control signal No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.

Air heater

Attribute "Valve type" set to "2-way valve" or "3-way valve"

Pin Required Mapping info
Operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Pump operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Valve position No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.
Valve control signal No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.

Boiler

Pin Required Mapping info
Operating message Yes General operating message of the boiler unit.
Pump operating message Yes Operating message of the feeding pump.

Combined heat and power

Pin Required Mapping info
Operating message Yes General operating message of the CHP.
Pump operating message Yes Operating message of the (cooling) pump.

Compression chiller

Pin Required Mapping info
Operating message Yes General operating message of the compression chiller.
Condenser pump operating message No At least one pump operating message has to be connected.
Evaporator pump operating message No At least one pump operating message has to be connected.

Heat pump

Pin Required Mapping info
Operating message Yes General operating message of the heat pump.
Condenser pump operating message No At least one pump operating message has to be connected.
Evaporator pump operating message No At least one pump operating message has to be connected.

Heat transfer unit

Pin Required Mapping info
Operating message No Mapping of either pump operating message - secondary (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Pump operating message - secondary No Mapping of either pump operating message - secondary (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Valve position No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.
Valve control signal No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.

Thermal control loop

Attribute "Valve type" set to "2-way valve" or "3-way valve"

Pin Required Mapping info
Operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Pump operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, the pump operating message is used.
Valve position No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.
Valve control signal No Mapping of either valve position (preferred) or valve control signal is mandatory. If both pins are mapped, the valve position is used.

Recommend Time Span

1 week


Recommended Repetition

Every 3 months

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Temperature Spread Analysis

The Temperature Spread Analysis assesses the temperature difference between a supply and return temperature sensor of a heat or cold distribution system during the system's operation. While a small temperature spread indicates the potential for volume flow and therefore pump power consumption reduction, a huge spread indicates thermal undersupply of the downstream systems and consumers.

Value

  • Higher occupant comfort, health and performance
  • Higher energy efficiency
  • Lower operating costs

Recommended for components

Heat and cold distribution systems, such as

  • Thermal control loop

Checked conditions

  • Temperature spread is too small causing volume flows that are too high, evaluation is component-specific
  • Temperature spread is too large and risk sufficient energy supply, evaluation is component-specific
  • Temperature spread is as expected, evaluation is component-specific
  • Condition checks on times of component's operation

The Temperature Spread Analysis was applied to a heating circuit instantiated as a thermal control loop.

temperature-spread-analysis
Figure 1: Outlet temperature and return temperature of the thermal control loop

Analysis for one week in May 2020 is shown in figure 1. A small temperature spread "temperature spread.mean" is calculated for this period of 5 °C. Thus a recommendation to reduce the volume flow of the heating circuit is returned to the user.

KPI Value Unit
operating time 84.9 h
operating mode heating
inlet temperature recirculation.mean 40.4 °C
outlet temperature.mean 45.4 °C
temperature spread.mean 4.94 °C
temperature spread.median 4.68 °C
temperature spread.minimum -4.24 °C
temperature spread.maximum 22.3 °C

Signal colors

Signal color Available Info
red No Red as a signal for a low cost measure with high impact on the building operation will not be provided.
yellow Yes Temperature spreads usually can be optimized by volume flow adjustments. Savings allow for medium-term amortization
green Yes Sufficient temperature spread in respect to usual tolerances in buildings

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations on how to adjust volume flows for higher energy efficiency or better energy provision. No recommendation, if temperature spread is sufficient.

KPIs

General

KPI Identifier Description Value Range Unit
operating time Amount of time component is switched on 0 to inf h

Statistics of temperature spread

Temperature spread

The temperature spread is always positive!

KPI Identifier Description Value Range Unit
temperature spread.maximum Maximum of temperature spread 0 to inf °C
temperature spread.mean Mean of temperature spread 0 to inf °C
temperature spread.median Median of temperature spread 0 to inf °C
temperature spread.minimum Minimum of temperature spread 0 to inf °C

Specific for compression chillers

Compression chiller

The KPI identifiers are extended by the prefix condenser or evaporator to specify the side of the compression chiller the Temperature Spread Analysis is applied on.
Example evaporator: temperature spread.minimum will be evaporator.temperature spread.minimum

Operating mode

The evaoprator "operating mode" should be cooling and the condenser "operating mode" should be heating. Any other combination will result in a warning.

Specific for air coolers/heaters

KPI Identifier Description Value Range Unit
operating mode Indication of heat transfer heating, cooling, neutral -
Return temperature - water side.mean Mean of return temperature - water side 0 to inf °C
Supply temperature - water side.median Median of supply temperature - water side 0 to inf °C

Specific for cooling/heating circuits

KPI Identifier Description Value Range Unit
operating mode Indication of heat transfer heating, cooling, neutral -
Return temperature.mean Mean of return temperature 0 to inf °C
Outlet temperature.median Median of outlet temperature 0 to inf °C

Specific for heat pumps

Heat pump

The KPI identifiers are extended by the prefix condenser or evaporator to specify the side of the heat pump the Temperature Spread Analysis is applied on.
Example evaporator: temperature spread.minimum will be evaporator.temperature spread.minimum

Operating mode

The evaoprator "operating mode" should be cooling and the condenser "operating mode" should be heating. Any other combination will result in a warning.

Specific for heat transfer units

Heat transfer units

The KPI identifiers are extended by the prefix primary or secondary to specify the side of the heat transfer unit the Temperature Spread Analysis is applied on.
Example primary: temperature spread.minimum will be primary.temperature spread.minimum

Operating mode

The primary and secondary "operating mode" work in sync and are checked to be the same.

Specific for recooling plants

KPI Identifier Description Value Range Unit
operating mode Indication of heat transfer heating, cooling, neutral -
Return temperature.mean Mean of return temperature 0 to inf °C
Supply temperature.median Median of supply temperature 0 to inf °C

Specific for thermal control loops

KPI Identifier Description Value Range Unit
operating mode Indication of heat transfer heating, cooling, neutral -
Inlet temperature recirculation.mean Mean of inlet temperature recirculation 0 to inf °C
Outlet temperature.median Median of outlet temperature 0 to inf °C

Air cooler

Pin Required Mapping info
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Return temperature - water side Yes -
Supply temperature - water side Yes -

Air heater

Pin Required Mapping info
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Return temperature - water side Yes -
Supply temperature - water side Yes -

Boiler

Pin Required Mapping info
Inlet temperature Yes -
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Outlet temperature Yes -

Combined heat and power

Pin Required Mapping info
Inlet temperature Yes -
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Outlet temperature Yes -

Compression chiller

Pin Required Mapping info
Inlet temperature condenser No Required, if condenser shall be analyzed
Outlet temperature condenser No Required, if condenser shall be analyzed
Inlet temperature evaporator No Required, if evaporator shall be analyzed
Outlet temperature evaporator No Required, if evaporator shall be analyzed
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on

Cooling circuit

Pin Required Mapping info
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Return temperature Yes -
Supply temperature Yes -
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on

Heat pump

Pin Required Mapping info
Inlet temperature condenser No Required, if condenser shall be analyzed
Inlet temperature evaporator No Required, if evaporator shall be analyzed
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Outlet temperature condenser No Required, if condenser shall be analyzed
Outlet temperature evaporator No Required, if evaporator shall be analyzed
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on

Heat transfer unit

Pin Required Mapping info
Operating message No Mapping of either Pump operating message - secondary (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message - secondary is used.
Default: Always on
Return temperature - primary No Required, if primary side shall be analyzed
Return temperature - secondary No Required, if secondary side shall be analyzed
Supply temperature - primary No Required, if primary side shall be analyzed
Supply temperature - secondary No Required, if secondary side shall be analyzed
Pump operating message - secondary No Mapping of either Pump operating message - secondary (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message - secondary is used.
Default: Always on

Heating circuit

Pin Required Mapping info
Operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on
Return temperature Yes -
Supply temperature Yes -
Pump operating message No Mapping of either Pump operating message (preferred) or Operating message is recommended. If both pins are mapped, Pump operating message is used.
Default: Always on

Recooling plant

Pin Required Mapping info
Return temperature Yes Return temperature
Operating message No Mapping of either Operating message fan (preferred) or Operating message is recommended. If both pins are mapped, Operating message fan is used.
Default: Always on
Operating message fan No Mapping of either Operating message fan (preferred) or Operating message is recommended. If both pins are mapped, Operating message fan is used.
Default: Always on
Supply temperature Yes Supply temperature

Thermal control loop

Pin Required Mapping info
Operating message No Mapping of either pump operating message (preferred) or operating message is mandatory. If both pins are mapped, pump operating message is used Default: Always on
Outlet temperature Yes -
Pump operating message No Mapping of either pump operating message (preferred) or operating message is strongly recommended. If both pins are mapped, valve position is used Default: Always on
Inlet temperature recirculation Yes -

Recommend Time Span

1 day to 1 week


Recommended Repetition

Every month

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Thermal Comfort Analysis

The Thermal Comfort Analysis evaluates the comfort level of a room by determining the indicators PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfied). They are calculated from room air temperature, room air humidity, and expected level of clothing depending on the outdoor temperature. Influences on thermal comfort in rooms like thermal exchange by radiation and influences of drafts are simplified in the determination.

Value

  • Check and evaluate the room comfort level
  • Higher occupant comfort, health and performance

Recommended for components

  • Rooms with usual conditioning like offices, schools, salesrooms

Checked conditions

  • Sufficient thermal comfort

For this example, we look at a room for an analysis period of two days as shown in figure 1. In this time we can categorize the room comfort level according to the comfort level categories in the table below. The PMV level stays inside the neutral category for the entire 48 hour period.

thermal-comfort-analysis
Figure 1: Temperatures and humidity while presence over a two days period in march

KPI Value Unit
operating time 48 h
operating time.relative 100 %
predicted percentage of dissatisfied.mean 11.3 %
predicted percentage of dissatisfied.median 9.66 %
predicted percentage of dissatisfied.maximum 41.1 %
predicted percentage of dissatisfied.minimum 5.0 %
predicted mean vote.mean -0.483 n.a.
predicted mean vote.median -0.472 n.a.
predicted mean vote.maximum 0.0831 n.a.
predicted mean vote.minimum -1.32 n.a.
duration.predicted mean vote.hot 0 h
duration.predicted mean vote.warm 0 h
duration.predicted mean vote.warmish 0 h
duration.predicted mean vote.neutral 25 h
duration.predicted mean vote.coolish 23 h
duration.predicted mean vote.cool 0 h
duration.predicted mean vote.cold 0 h
duration.category A.relative 8.33 %
duration.category B.relative 43.8 %
duration.category C.relative 22.9 %
duration.no category.relative 25.0 %
duration.predicted mean vote.neutral 48 h

Signal colors

Signal color Available Info
red Yes Room comfort level is insufficient
yellow Yes Room comfort level is sufficient
green Yes Room comfort level is good

Interpretations

Available Info
Yes Evaluation of the room comfort level for peak and average values

Recommendations

Available Info
Yes Recommendations to improve the room comfort level

KPIs

Temperatures

KPI Identifier Description Value Range Unit
room.temperature.mean Average room temperature during presence and analysis period inf °C
room.relative humidity.mean Average relative humidity for room during presence and analysis period 0 to 100 %
outdoor temperature.mean Average outdoor temperature during presence and analysis period inf °C

Operating Time

KPI Identifier Description Value Range Unit
operating time Duration of presence, respectively active room control if presence is not measured 0 to inf h
operating time.relative Duration of presence, respectively active room control if presence is not measured, relative to analyzed time 0 to 100 %

Predicted Mean Vote - PMV

Following the Climate Assessment Scale of DIN EN ISO 7730, 2006 with

PMV Value Classification
pmv > 2.5 hot
1.5 < pmv <= 2.5 warm
0.5 < pmv <= 1.5 warmish
-0.5 <= pmv <= 0.5 neutral
-1.5 <= pmv < -0.5 coolish
-2.5 <= pmv < -1.5 cool
pmv < -2.5 cold
KPI Identifier Description Value Range Unit
predicted mean vote.mean Average of PMV for analysis period -3 to 3 -
predicted mean vote.median Median of PMV for analysis period -3 to 3 -
predicted mean vote.maximum Maximum PMV reached during analysis period -3 to 3 -
predicted mean vote.minimum Minimum PMV reached during analysis period -3 to 3 -
duration.predicted mean vote.hot Duration the PMV is classified as hot 0 to inf h
duration.predicted mean vote.warm Duration the PMV is classified as warm 0 to inf h
duration.predicted mean vote.warmish Duration the PMV is classified as warmish 0 to inf h
duration.predicted mean vote.neutral Duration the PMV is classified as neutral 0 to inf h
duration.predicted mean vote.coolish Duration the PMV is classified as coolish 0 to inf h
duration.predicted mean vote.cool Duration the PMV is classified as cool 0 to inf h
duration.predicted mean vote.cold Duration the PMV is classified as cold 0 to inf h

Predicted Percentage of Dissatisfied - PPD

KPI Identifier Description Value Range Unit
predicted percentage of dissatisfied.mean Average of PPD for analysis period 0 to 100 %
predicted percentage of dissatisfied.median Median of PPD for analysis period 0 to 100 %
predicted percentage of dissatisfied.maximum Maximum PPD reached during analysis period 0 to 100 %
predicted percentage of dissatisfied.minimum Minimum PPD reached during analysis period 0 to 100 %

Comfort Level Categories

According to norm DIN EN 15251, 2007

Category PMV
A -0,2 < PMV < +0,2
B -0,5 < PMV < +0,5
C -0,7 < PMV < +0,7
KPI Identifier Description Value Range Unit
duration.category A.relative Percentage of time the room comfort level corresponds to category A 0 to 100 %
duration.category A Duration that the room comfort level corresponds to category A 0 to inf h
duration.category B.relative Percentage of time the room comfort level corresponds to category B 0 to 100 %
duration.category B Duration that the room comfort level corresponds to category B 0 to inf h
duration.category C.relative Percentage of time the room comfort level corresponds to category C 0 to 100 %
duration.category C Duration that the room comfort level corresponds to category C 0 to inf h
duration.no category.relative Percentage of time the room comfort level corresponds to no category 0 to 100 %
duration.no category Duration that the room comfort level corresponds to no category 0 to inf h

Time series

KPI Identifier Description Value Range Unit
predicted mean vote.time series Timeseries with the PMV value for each observation -3 to 3 -
predicted percentage of dissatisfied.time series Timeseries with the PPD value for each observation 0 to 100 %
category.time series Timeseries with a category classification for each observation A, B, C, NOCAT string

Economic KPIs

Economic KPIs estimate the economic optimization potential of the observed operational state. The KPIs indicate the possible productivity gains and the resulting salary savings for adjusting the thermal state to the thermal comfort range. The thermal comfort range is defined by PMV category B (-0.5 < PMV < 0.5). Category B describes a normal level of expectation, according to DIN EN 15251:2012-12.

The Economic KPIs are provided for the components:

  • Room

Their availability and accuracy depend on the component's mapping. The analysis function always determines the highest possible accuracy.

Accuracy Levels:

High

Components Pins Attributes
Room Presence or Operating message
Temperature
Humidity
Outside air temperature
Complementary:
Room type (used in combination with "Presence" or "Operating message" to estimate room usage).

Medium

Components Pins Attributes
Room Temperature
Humidity
Outside air temperature
Schedule
Complementary:
Custom day schedule
Schedule timezone
Custom holiday
Regional key
Room type (used in combination with pins Schedule attributes to estimate room usage).

Low

Components Pins Attributes
Room Temperature
Humidity
Outside air temperature
Assumption of 24/7 usage
Complementary:
Room type (used to estimate room usage).

All Accuracy Levels

Components Pins Attributes
Room - Average salary
Occupation max

Salary savings KPIs: Required additional mapping to all accuracy levels.

Components Pins Attributes
Room - Average salary
Occupation max

Salary savings KPIS

KPI Identifier Description Value Range Unit
thermal comfort salary savings.daily Identified salary savings potential from employee productivity losses for the thermal state outside of comfort limits (Category B). The savings are provided as average daily savings potential. 0 to inf €/day
thermal comfort salary savings.weekly Identified salary savings potential from employee productivity losses for the thermal state outside of comfort limits (Category B). The savings are provided as average weekly savings potential if the analyzed period is at least one week long. 0 to inf €/week

Productivity Gains KPI

KPI Identifier Description Value Range Unit
thermal comfort productivity gains.relative Identified percentual productivity gains for adjusting the thermal state to the comfort range (Category B). 0 to 100 %

Room

Pin Required Mapping info Unit
Temperature Yes - °C
Humidity Yes - %
Outside air temperature Yes - °C
Operating message No Mapping of either presence (preferred) or operating message is strongly recommended. If both pins are mapped, presence is used Default: Always presence binary
Presence No Mapping of either presence (preferred) or operating message is strongly recommended. If both pins are mapped, presence is used Default: Always presence binary
Attribute Required Mapping info Unit
Average salary No Necessary for Salary savings KPIs of Economic KPIs, all accuracy levels. €/person
Occupation max No Necessary for Salary savings KPIs of Economic KPIs, all accuracy levels. -
Room type No Available values:
- 24/7 full occupancy
- classroom
- single person office multi persons office
- store
- restaurant
- conference room
- kindergarten
Default: 24/7 full occupancy
-
Schedule timezone No Default: UTC -
Custom day schedules No Default: None -
Regional key No Default: None -
Schedule No Default: None -

Recommend Time Span

1 week


Recommended Repetition

Every month

  • After changes of presence schedules or room schedules

Virtual Heat Meter Analysis

The Virtual Heat Meter Analysis determines the heat flow and energy delivered in heating/cooling piping networks such as thermal control loops or energy conversion plants. The determination is either based on the temperature difference and volume flow, or the readings from a physical heat meter in the field. It substitutes physical heat meters and enables energy flow tracing.

Value

Quantifies heat flow and heat:

  • Traces energy flow
  • Enable other analytics functions
  • Enables comparison to hardware heat meters

Recommended for components

Heat and cold conversion or distribution systems, such as

  • Boilers
  • Combined heat and power
  • Heat meters
  • Heat pumps
  • Thermal control loops

Checked conditions

  • Determines heat flow from temperature difference and volume flow for several components.
  • Condition checks on times of components operation.
  • Compares the measured heat with the virtual heat (calculated by analysis), if both are available.

The virtual heat meter analysis was tested on a combined heat and power plant for one week. Figure 1 shows the inlet/outlet temperatures, volume flow, and heat flow of the combined heat and power plant.

virtual-heat-meter
Figure 1: Temperatures, volume flow and heat flow of combined heat and power plant

The virtual heat is compared with the measured heat and based on the relatively small difference between the two heats, a green signal color is returned.

KPI Value Unit
measured heat 43.4 MWh
measured heat flow.mean 444.6 kW
measured heat flow.minimum 0.1 kW
measured heat flow.maximum 1113.1 kW
measured heat flow.median 595.8 kW
virtual heat 41.4 MWh
virtual heat flow.mean 324.1 kW
virtual heat flow.minimum -1213.2 kW
virtual heat flow.maximum 1061.8 kW
virtual heat flow.median 548.9 kW
heat difference 2.01 MWh
heat difference.relative 4.63 %

The analysis only returns recommendations and evaluations if both a measured heat/heat flow is available, and a virtual heat is calculated. Otherwise, only KPI results are returned.

Signal colors

Signal color Available Info
red No -
yellow Yes There is a significant difference between the virtual heat and the measured heat for this component or its sub-components.
green Yes There is no significant difference between the virtual heat and the measured heat for this component and all of its sub-components.

Interpretations

Available Info
Yes Either the operational rule checks of the analysis were tested positive or not

Recommendations

Available Info
Yes Consider re-calibrating the heat meter

KPIs

Statistics of heat flow

Negative values indicate cooling, while positive indicate heating.

Virtual and measured heat:

The "virtual heat" refers to heat calculated using temperatures and volume flows where "measured heat" refers to heats supplied by physical heat meters. The KPIs and time series are available for both cases and referred to as either measured or virtual heats e.g.:

measured heat flow is the heat flow measured by a heat meter

Units:

The units of the returned heat and heat flow are selected according to the magnitude of the result. Typical units are presented in the table below. Other possible units include MWh for heat and MW or W for heat flow.

Heat pump:

The KPI identifiers are extended by the prefix condenser or evaporator to specify the side of the heat pump the virtual heat meter is applied on. E.g.:

heat flow.maximum will be evaporator heat flow.maximum

KPI Identifier Description Value Range Unit
heat flow.maximum Largest heat flow -inf to inf kW
heat flow.minimum Smallest heat flow -inf to inf kW
heat flow.mean Average heat flow -inf to inf kW
heat flow.median Median heat flow -inf to inf kW
heat Aggregated heat transferred -inf to inf kWh
heat difference Difference between measured and virtual heat -inf to inf kWh
heat difference.relative Percentage difference between virtual and measured heat 0 to 100 %

Time series

KPI Identifier Description Value Range Unit
heat flow.time series Timeseries of transferred heat -inf to inf kW
heat flow.cumulated Timeseries of cumulated transferred heat -inf to inf kWh

Boiler

Pin Required Mapping info
Inlet temperature No -
Outlet temperature No -
Volume flow No -
Heat No -
Heat flow No -
Attribute Required Mapping info
Heat flow unit No Default: kW
Heat unit No Default: kWh
Volume flow unit No Default: litersPerSecond

Combined heat and power

Pin Required Mapping info
Inlet temperature No -
Outlet temperature No -
Volume flow No -
Volume flow No -
Heat No -
Heat flow No -
Attribute Required Mapping info
Heat flow unit No Default: kW
Heat unit No Default: kWh
Volume flow unit No Default: litersPerSecond

Heat meter

Pin Required Mapping info
Inlet temperature No -
Outlet temperature No -
Volume flow No -
Heat No -
Heat flow No -
Attribute Required Mapping info
Heat flow unit No Default: kW
Heat unit No Default: kWh
Volume flow unit No Default: litersPerSecond

Heat pump

The Virtual Heat Meter is determined on the condenser and evaporator side depending on the mapped datapoints.

Pin Required Mapping info
Condenser inlet temperature No Required, if condenser shall be analyzed
Condenser outlet temperature No Required, if condenser shall be analyzed
Condenser volume flow No Required, if condenser shall be analyzed
Condenser heat flow No Required, if condenser shall be analyzed
Condenser heat No Required, if condenser shall be analyzed
Evaporator inlet temperature No Required, if evaporator shall be analyzed
Evaporator outlet temperature No Required, if evaporator shall be analyzed
Evaporator volume flow No Required, if evaporator shall be analyzed
Evaporator heat flow No Required, if evaporator shall be analyzed
Evaporator heat No Required, if evaporator shall be analyzed
Attribute Required Mapping info
Heat flow unit No Default: kW
Heat unit No Default: kWh
Volume flow unit No Default: litersPerSecond

Attributes

The units used for this analysis need to be specified for the analysis to yield correct results. If unspecified, the default unit is taken.

Heat flow unit

default: kW

Available units:

  • W
  • kW
  • MW
  • GW

Heat unit

default: kWh

Available units:

  • Wh
  • kWh
  • MWh
  • GWh

Volume flow unit:

Default: litersPerSecond

Available units:

  • cubicMetersPerSecond
  • cubicMetersPerMinute
  • cubicMetersPerHour
  • litersPerSecond
  • litersPerMinute
  • litersPerHour

Recommend Time Span

1 day to 1 month


Recommended Repetition

Every month

Weather Station Analysis

Two important sensors for HVAC system control are the outdoor air temperature sensor and the outdoor air humidity sensor. Many control decisions, e.g., what amount of heat/humidity is to be provided, and the switching between heating and cooling modes, are made based on the measured outdoor temperature and humidity. The sensors are prone to wear out over the lifetime of the building. Furthermore, the sensors are often influenced by solar radiation or heat emitted from components in its surrounding. Wrongly measured outside air temperature or humidity directly corresponds to a thermal over/undersupply of the building or incorrect indoor humidity, often leading to poor user comfort and increased energy consumption.

The Weather Station Analysis identifies installation errors and measurement offsets of the outdoor air temperature sensor and derives optimization measures for better outdoor air temperature measuring.

This analysis can only be performed for periods of at least one week. Furthermore, the minute and second values of the start and end times are disregarded in the calculation to accommodate the full hours of the weather data (i.e., "2020-01-01 01:12:55" becomes "2020-01-01 01:00:00").

Value

  • Higher operational performance due to reliable information about outside air conditions
  • Higher occupant comfort, health, and performance
  • Lower operating costs
  • Better system coordination in systems with redundant sensors

Recommended for components

  • Weather station

Checked conditions

  • Offset between measured outdoor air temperature and weather service reference data
  • Offset between measured outdoor air humidity and weather service reference data
  • Outdoor air temperature sensor is mistakenly influenced by solar radiation
  • Outdoor air temperature sensor is mistakenly influenced by its surrounding, e.g., exhaust gases
  • Outdoor air temperature measures are compliant to weather service reference data

For this Weather Station Analysis we instantiated a "weather station" component and analyzed a week of weather data. The following plot shows the measured temperature of a sensor located at a building facade. During the reviewed period in the summer, the sensor is influenced in the afternoon.

outdoor-temperature-sensor-analysis
Figure 1: Measured data outdoor air temperature and reference outdoor air temperature

In figure 1 you can see a significant difference between sensor and weather reference. This is also reflected in the value of the calculated KPIs. During the analysis period, all 7 days are recognized by the KPI as "radiation influenced days". Additionally, the offset at night is elevated and thus a larger "sensor offset squared error" is present.

KPI Value Unit
radiation influenced.relative 100 %
radiation influenced days 7 count
offset RMSE 7.3 Kelvin
offset ME 6.4 Kelvin

Signal colors

Signal color Available Info
red Yes Significant solar radiation influence and/or offset identified
yellow Yes Partial solar radiation influence and/or moderate offset identified
green Yes Sufficient accuracy of outdoor air temperature measurements

Interpretations

Available Info
Yes Interpretations summarize the result of the analysis

Recommendations

Available Info
Yes Recommendations to improve outdoor air temperature measurement, if necessary or re-calibrate the sensor, if physically implausible measures are observed. No recommendation, in case of sufficient measurement quality.

KPIs

KPI Identifier Description Value Range Unit
radiation influenced days.relative Ratio of days with more than one hour of sun radiation influence to days analyzed 0 to 100 %
radiation influenced days Days with more than one hour of sun radiation influence 0 to inf days
offset RMSE Root mean square error of the offset between measured outdoor air temperature and the reference data set. 0 to inf Kelvin
offset ME Mean error of the offset between measured outdoor air temperature and the reference data set. -inf to inf Kelvin

Sensor errors

KPI Identifier Description Value Range Unit
Temperature RMSE Root mean square error between the measured outdoor air temperature and the reference data set. 0 to inf Kelvin
Temperature ME Mean error between the measured outdoor air temperature and the reference data set. -inf to inf Kelvin
Humidity RMSE Root mean square error between the measured outdoor relative humidity and the reference data set. 0 to 100 %
offset ME Mean error of the offset between measured outdoor air temperature and the reference data set. -inf to inf Kelvin

Weather station

Pin Required Mapping info
Temperature No Mandatory for outside air temperature checkup
Humidity No Mandatory for outside air humidity checkup
Attribute Required Mapping info
Latitude Yes -
Longitude Yes -

Recommend Time Span

1 month


Recommended Repetition

Every month

  • After changes of operational modes, e.g., transfers to heating mode
  • After changes in the control system
  • After maintenance or replacements

Information

The library of analytics functions is constantly expanding. If you are missing an analytics function, wish to implement your own functions, or want us to implement it for you, feel free to contact us.


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