FB_BA_H_HtgCir01

Template FB_BA_H_HtgCir01 is used to program a static heating circuit.

The main components of the template are:

Flow temperature control.
Heating curve dependent on outside temperature with night setback.
Operation mode selection.
Control of the heating circuit pump.
Control of an analog control valve.

	The initialization of the template takes place within the method FB_Init.

Fault shutdown

The plant switches off at:

Fault in the heating circuit pump
Fault in the flow temperature sensor

The following table lists the event-capable objects of the template that can trigger relevant PlantLock faults. The parameterization of the lock priority of these events can be found in FB_init.

Function block	eEnPlantLock	Function block	bPrioHigh	bPrioMedium
TFl.MV	E_BA_LockPriority.eMedium	PlantLock		X
Pu.Dst	E_BA_LockPriority.eMedium		X

Function block

eEnPlantLock

Function block

bPrioHigh

bPrioMedium

TFl.MV

E_BA_LockPriority.eMedium

PlantLock

Pu.Dst

E_BA_LockPriority.eMedium

Principle diagram

The principle diagram shows the intended use of the template with the plant elements involved.

Block diagram

Syntax

FUNCTION_BLOCK FB_BA_H_HtgCir01 EXTENDS FB_BA_View
VAR_OUTPUT
  eOpMod       : E_BA_EnergyLvl;
  bRls         : BOOL;
  fSp          : REAL;
  bPu          : BOOL;
  fVlv         : REAL;
END_VAR
VAR_INPUT CONSTANT
  TFl          : FB_BA_SensorAnalog_Raw;
  TRt          : FB_BA_SensorAnalog_Raw;
  Vlv          : FB_BA_Vlv;
  Pu           : FB_BA_Pu1st;
  Sp           : FB_BA_H_HtgCir_Sp;
  OpMod        : FB_BA_H_OpMod;
  HtgLmt       : FB_BA_HtgLmt;
  TFlCtrl      : FB_BA_PID;
  PlantLock    : FB_BA_PlantLock;
END_VAR

Outputs

Name	Type	Description
eOpMod	E_BA_EnergyLvl	Operation mode of the heating circuit.
bRls	BOOL	The variable indicates that the heating circuit is in operation.
fSp	REAL	Calculated setpoint of the heating characteristic curve.
bPu	BOOL	Heating circuit pump is active.
fVlv	REAL	Calculated control value for the control valve.

Inputs CONSTANT

Name	Type	Description
TFl	FB_BA_SensorAnalog	The function block represents the flow temperature.
TRt	FB_BA_SensorAnalog	The function block represents the return temperature.
Vlv	FB_BA_Vlv	Control valve
Pu	FB_BA_Pu1st	Heating circuit pump
Sp	FB_BA_H_HtgCir_Sp	The function block calculates the setpoint for the flow temperature based on the damped outside temperature and the frost protection setpoint. The damped outside temperature Site.stGeneralSettings.fTWthDamped and the frost protection setpoint Site.stGeneralSettings.fFrostProtectionSetpoint originate from the global variable list Site.
OpMod	FB_BA_H_OpMod	Operation mode selection of the heating circuit (Auto, Protection, Economy and Comfort). The variable Site.stGeneralSettings.bTWthLowLimit indicates that the outside temperature has fallen below the lower limit and the frost protection function is therefore active.
HtgLmt	FB_BA_HtgLmt	The heating limit switch integrated in the function block enables automatic heating operation depending on the damped outside temperature. The damped outside temperature Site.stGeneralSettings.fTWthDamped originates from the global variable list Site.
TFlCtrl	FB_BA_PID	Flow temperature control of the heating circuit.
PlantLock	FB_BA_PlantLock	When the function block is called, the relevant faults of the event-enabled objects are collected and output at this and lower levels of the heating circuit. These relevant faults trigger the E_BA_EnergyLvl.eProtection operation mode in the OpMod operation mode program. As a result, the heating circuit is switched to the E_BA_EnergyLvl.eProtection operation mode. A list of the faults that shut down the plant can be found under Fault shutdowns.