BAC_AC_ErcRecup_01
Application
The template BAC_AC_ErcRecup_01 is used for control and anti-icing of an energy recovery unit with a run-around-coil system.
The template BAC_AC_ErcRecup_01 is a call template.
Within the call template the following subtemplates are called and linked with each other:
- ErcRetWtrT: return temperature of the run-around-coil system
- ErcSuA_PID: control of the supply air temperature
- ErcExhA_PID: minimum limitation of exhaust air temperature
- ErcPu control of the circulation pump
- ErcRetWtr_PID: minimum limitation of the water temperature at the heat exchanger return in the exhaust air of the run-around-coil system
- ErcIcPrt_01: anti-icing for the heat exchanger in the exhaust air of the run-around-coil system with differential pressure switch
- ErcVlv: control of an analog control valve in the water/glycol circuit
The return water temperature controller ErcRetWtr_PID, the exhaust air minimum limiter ErcExhA_PID and the frost protection program ErcIcPrt limit the control value of the supply air temperature controller ErcSuA_PID of the energy recovery unit via the minimum value option, in order to prevent icing up of the heat exchanger.
Interface
Plant diagram 01
Plant diagram 02
Block diagram
VAR_INPUT
rSuAT : REAL;
rSpErc : REAL;
udiPltStp : UDINT;
udiOpMod : UDINT;
bDeHum : BOOL;
rExhAT : REAL;
rExtAT : REAL;
rSuAT: Measured value supply air temperature
rSpErc: Set value supply air temperature
udiPltStp: Plant start sequence steps. The plant steps are generated in the system start program BAC_AC_StartT_01.
udiOpMod: Plant operation mode. The plant operation mode is determined in the mode selection program BAC_AC_OpMod_01.
bDeHum: Status message dehumidification mode. Disabling of energy recovery in heating mode (outside temperature > outlet air temperature) .
rExhAT: Measured value exhaust air temperature
rExtAT: Measured value outlet air temperature
VAR_OUTPUT
bActn : BOOL;
bActn: control direction of the supply air temperature control SuA_PID. The control direction of the energy recovery is required by various setpoint programs or cascade controllers for determining setpoint for the supply air temperature of the energy recovery unit, e.g. BAC_AC_SpSuAT_02, BAC_AC_CasCtrlT_02.
Program description
Instance | Type | Task |
|---|---|---|
RetWtrT | Subtemplate return temperature of the run-around-coil system | |
SuA_PID | Subtemplate supply air temperature control. The temperature control is analog via PID sequence controller | |
ExhA_PID | Subtemplate exhaust air temperature control for anti-icing | |
RetWtrT_PID | Subtemplate return temperature control for anti-icing | |
IcPrt | Subtemplate for anti-icing of an energy recovery unit via differential pressure switch | |
Vlv | Template for controlling an analog valve | |
Pu | Template for controlling a single-stage pump | |
| MIN, MIN, MIN | MIN selection of the control signals for supply air temperature control SuA_PID, exhaust air temperature control ExhA_PID, return temperature control RetWtrT_PID and frost protection ramp function |
Version history
Version number | Comments |
|---|---|
1.0.1 | First release |