[DhwStk21] Domestic hot water storage tank
Program block, name / node subtype: [DhwStk21] Domestic hot water storage tank
Library hierarchy: Heating equipment
Family: DhwStk
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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.
Storage tank charge
Clear temperature stratification is not expected since an internal heat exchanger is used for charging.
Two sensors are planned: One sensor in the top and one in the bottom area of the storage tank. The two temperatures determine the state of charging.
Key
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SpTTank | Tank temperature setpoint |
TTnk | Tank temperature |
TTnkTop | Tank temperature, top |
TTnkBtm | Tank temperature, bottom |
Charging required:
The storage tank is discharged and charging is required if the high temperature sensor is below the setpoint minus a switching differential, e.g., 1 K.
Charged:
The storage tank is charged if both temperature sensors are above the setpoint.
The storage tank is charged with the storage tank charging circuit.
Special case:
The switching differential is automatically increased, e.g., by 5 K, in the event that the top sensor fails or if there is only one sensor (in the middle of the storage tank and connected as TTnkBtm).
Name | Description | Type | Alarm / Notification class | Trend / Type | |
|---|---|---|---|---|---|
TTnkTop | Tank temperature, top | AI: Analog input | No | Yes, 3 | |
TTnkBtm | Tank temperature, bottom | AI: Analog input | No | Yes, 3 | |
SpTTnk | Tank temperature setpoint | ACnfVal: Analog configuration value | No | No | |