Parameters
On the Properties tab, you can configure the parameters through simple inputs:
- Object Name
The name of the TABS circuit.
- Description
A detailed description of the TABS circuit.
- Enable
Select this option to enable the automatic calculation of this TABS circuit.
- Setpoint
The output setpoint \((SP)\) of this circuit.
- Limiter Input
This is the calculated result of the TABS circuit before it is fed to the limiter, which will clamp the value between Minimum Output and Maximum Output. Read only.
- Output Reference
References the output data point of this circuit.
- Input Insolation
The input insolation \((PV_{Inso.})\) in Wh/m². Read only.
- Insolation Setpoint
The insolation setpoint \((SP_{Inso.})\) in Wh/m².
- Insolation Proportional Gain
The proportional gain \(K_{Inso.p}\) for calculating the insolation output value.
\(P_{Inso.} = K_{Inso.p} \, e_{Inso.}(t)\)
\(P_{Inso.}\): Output insolation
\(e_{Inso.}(t) = SP_{Inso.} - PV_{Inso.}\)
\(K_{Inso.p}\): Proportional gain
\(SP_{Inso.}\): Insolation setpoint
\(PV_{Inso.}\): Input insolation
- Output Insolation
The output insolation in K.
- Present Value
The present value of the circuit. Read only.
- Maximum Output
The maximum output value in °C. The output value will be clamped if it exceeds this value.
- Minimum Output
The minimum output value in °C. The output value will be clamped if it falls below this value.
- Unit
The unit of the output value. Read only.
- Input Temperature
The input temperature \((PV_{Temp.})\) in °C. This corresponds to the forcast temperature.
- Temperature Setpoint
The setpoint of the temperature \((SP_{Temp.})\) in °C.
- Temperature Heating Gain and Temperature Cooling Gain
The proportional gain for calculating the output temperature when the difference between setpoint and input is either < 0 (heating) or ≥ 0 (cooling), respectively.
\(P_{Temp.} = K_{Temp.p} \, e_{Temp.}(t)\)
\(P_{Temp.}\): Output temperature
\(e_{Temp.}(t) = SP_{Temp.} - PV_{Temp.}\)
\(K_{Temp.p}\):
Proportional heating gain if \(e(t) < 0\)
Proportional cooling gain if \(e(t) ≥ 0\)
\(SP_{Temp.}\): Temperature setpoint
\(PV_{Temp.}\): Input temperature
- Output Temperature
The output temperature \((P_{Temp.})\) in K.
Block diagram
On the Block Diagram tab, you see a visual representation of the calculation, allowing you to see the connections between individual parameters.
You can click on any of the green shapes to set a new value for that particular parameter. Hovering over a particular shape will show its name in a tooltip.
See Parameters for a list of all available parameters.
Block diagram of a TABS circuit
Calculation
The output value of the TABS circuit is calculated as follows:
\(Output' = SP - K_{Temp.p} \, e_{Temp.}(t) + K_{Inso.p} \, e_{Inso.}(t)\) \(Output = max(min(Output', Output_{max}), Output_{min})\)
\(Output\): Output temperature written to the output reference data point
\(Output_{min}\): Minimum output value
\(Output_{max}\): Maximum output value
\(P_{Temp.}\): Output temperature
\(P_{Inso.}\): Output insolation
\(e_{Temp.}(t) = SP_{Temp.} - PV_{Temp.}\)
\(e_{Inso.}(t) = SP_{Inso.} - PV_{Inso.}\)
\(K_{Temp.p}\):
Proportional heating gain if \(e_{Temp.}(t) < 0\)
Proportional cooling gain if \(e_{Temp.}(t) ≥ 0\)
\(K_{Inso.p}\): Proportional insolation gain
\(SP\): Output setpoint
\(SP_{Temp.}\): Temperature setpoint
\(SP_{Inso.}\): Insolation setpoint
\(PV_{Temp.}\): Input temperature
\(PV_{Inso.}\): Input insolation
Change weather station
By default, the system uses weather forecast data from the weather station Zürich-Fluntern (SMA).
You can choose another weather station by clicking on More at the top left and then on Change Weather Station. In the following dialog, you can select any of the available weather stations and confirm with OK.