[Hpu22] Heat pump, 2-stage
Program block, name / node subtype: [Hpu22] Heat pump, 2-stage
Library hierarchy: Heating equipment
Family: HGen
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Configurator
Program blocks are stored in the library without I/Os. Use the auto-create and auto-connect functions to create I/Os and/or to connect them to the interface blocks, e.g., R_A, CMD_B. Alternatively, take the I/Os from the folder containing the predefined I/Os in the library and/or from the plant and connect them to the interface blocks.
Controls a heat pump with own external control unit.
An interface to the control unit of the heat pump (HpuItf25) enables stage 1 or stage 2, reads optional signals for fault, feedback, defrost status, and present power.
The program has settings for the nominal power of the heat pump and for the transient state times (a signal that the heat pump is in a transient state that blocks the logic for generating further step-up and step-down pulses for the power control and compensation) when switching on or off (e.g., 5 minutes when switching on and 2 minutes when switching off).
The switch-on and switch-off sequence for the valves, the pump, and the interface to the control unit are defined in the function block CMDSEQ_B.
This program block has the following optional functions:
Option: Pump (1xBO, 4xBI)
Controls a pump (Pu21). Different alternatives are possible, e.g., TwnPu21.
The pump runs when the heat pump is running, and the optional shutoff valve is open.
Option: Shutoff valve (1xBO, 2xBI)
Controls a shutoff valve that opens when the heat pump is running (Vlv21).
Option: Flow temperature (1xAI)
Creates an analog input for the flow temperature and reads its signal. It can generate an alarm (high and low limit).
Option: Frost protection
If the flow temperature (outlet) and/or the return temperature (inlet) of the heat pump fall below a certain value, e.g., 8 °C, the shutoff valve opens and the pump starts to ensure water circulation.
If the temperatures fall further, e.g., to 5 °C, the interface to the control of the heat pump enables the heat pump and the heat pump starts.
Option: Heating/cooling state
Reads the calculated heating/cooling state in another part of the program via BACnet and passes it on to the heat pump interface (HpuItf25).
Option: Operating mode switch (1xMI=2xBI)
Reads the state of an operating mode switch, normally at the front of the electrical panel, and has the states "Auto", "Off", and "On".
Option: Return temperature (1xAI)
Creates an analog input for the return temperature and reads its signal. It can generate an alarm (high and low limit).
Name | Description | Type | Alarm / Notification class | Trend / Type | |
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HpuItf | Heat pump interface | [HpuItf22] Heat pump interface, enable output 2-stage | N/A | N/A | |
PrSpT | Present temperature setpoint | ACalcVal: Analog calculated value | No | No | |
Name | Description | Type | Alarm / Notification class | Trend / Type | |
|---|---|---|---|---|---|
Pu | Pump | N/A | N/A | ||
VlvShof | Shutoff valve | N/A | N/A | ||
TFl | Flow temperature | AI: Analog input | Yes, 4 | Yes, 2 | |
TRt | Return temperature | AI: Analog input | Yes, 4 | Yes, 2 | |
OpModSwi | Operating mode switch | MI: Multistate input | No | Yes, 4 | |
FrPrt | Frost protection | BCalcVal: Binary calculated value | Yes, 5 | No | |
The extension for alarming for the predefined I/O for the optional element "Feedback" (in the program block interface) must be deactivated.