FB_BC9191FanCoil

Application

This function block maps a 3-stage fan. The three stages are switched via the control value (0...100%) of the heating or cooling controller. Furthermore there is a possibility to manually override the fan controller via the iStageManual or bStageUp or bStageDown input. A minimum switch-on time can be set via the udiSecMINPowerOnTime input, which is then valid for each stage.

VAR_INPUT

Name                    : Type

bSetDefault             : BOOL;
bEnable                 : BOOL;
eCtrlFct                : E_BC9191CtrlFct;
rY_C                    : REAL;
rY_H                    : REAL;
bStageUp                : BOOL;
bStageDown              : BOOL;
iStageManual            : INT;
bReset                  : BOOL;

bSetDefault: If the variable is TRUE, the default values of the VAR_IN_OUT variables are adopted.

bEnable: The function block is activated if the variable bEnable is TRUE. No fan stage is activated with a FALSE.

eCtrlFct: This input is connected to the eCtrlFct output of the FB_BC9191FctSelection. This information is important in order to know whether the plant is in heating or cooling mode. In automatic mode, the fan stages are only activated if

the system is in heating mode and according to the control deviation the request for heating is active or
the system is in cooling mode and according to the control deviation the request for cooling is active.

rY_C: Input for the control value from the cooling controller.

rY_H: Input for the control value from the heating controller.

bStageUp: Local adjustment of the fan stage, stepwise increase by push button.

bStageDown: Local adjustment of the fan stage, stepwise decrease by push button.

iStageManual: The manual fan stage can/is set centrally via this input.
iStageManual: = 0 corresponds to fan stage OFF
iStageManual: = 1 corresponds to fan stage AUTO
iStageManual: = 2 corresponds to fan stage01 active
iStageManual: = 3, corresponds to fan stage02 active
iStageManual: = 4, corresponds to fan stage03 active

bReset: Acknowledge input in case of a fault or an incorrect parameter.

VAR_OUTPUT

Name                      : Type

bStageOff                 : BOOL;
bStageAuto                : BOOL;
bStage01                  : BOOL;
bStage02                  : BOOL;
bStage03                  : BOOL;
bFanCoilActive            : BOOL;
bPresence                 : BOOL;
byState                   : BYTE;
byError                   : BYTE;
udiSecRT_MINPowerOnTime   : UDINT;
udiRT_TimePeriod          : UDINT;
bInvalidParameter         : BOOL;

bStageOff: TRUE, fan stages are switched off.

bStageAuto: TRUE, fan controller is in automatic mode.

bStage01: TRUE, fan stage01 active.

bStage02: TRUE, fan stage02 active.

bStage03: TRUE, fan stage03 active.

bFanCoilActive: TRUE if one of the three fan stages is active. This output can be/is used to enable controllers in order to avoid a build up of heat or cold.

bPresence: TRUE means that presence was detected via the bStageUp, bStageDown or iStageManual inputs.

byState: Indicates the state of the fan controller.
byState.0:= Function block is activated
byState.3:= Manual fan stage setting is active
byState.4:= bReset
byState.5:= Fan stage01 active
byState.6:= Fan stage02 active
byState.7:= Fan stage03 active

byError: Output of the errors as byte.
byError.1:= bInvalidParameter

udiSecRT_MINPowerOnTime: Indicates the remaining time of the minimum switch-on time.

udiRT_TimePeriod: Indicates the remaining time of the manual override.

bInvalidParameter: Indicates that an incorrect input parameter is present. bInvalidParameter must be acknowledged with bReset.

VAR_IN_OUT

Name                       : Type    Persistent      Default

rValvePositionH_Stage01    : REAL;     X              0         %
rValvePositionH_Stage02    : REAL;     X             21         %
rValvePositionH_Stage03    : REAL;     X             76         %
rValvePositionC_Stage01    : REAL;     X              0         %
rValvePositionC_Stage02    : REAL;     X             21         %
rValvePositionC_Stage03    : REAL;     X             76         %
udiSecMINPowerOnTime       : UDINT;    X            120        sec
iFctModeFanCoil            : INT;      X              3
udiTimePeriod              : UDINT;    X             60 min

rValvePositionH_Stage01: Limit value of the control value of the heating controller from which fan stage01 is switched on.

rValvePositionH_Stage02: Limit value of the control value of the heating controller from which fan stage02 is switched on.

rValvePositionH_Stage03: Limit value of the control value of the heating controller from which fan stage03 is switched on.

rValvePositionC_Stage01: Limit value of the control value of the cooling controller from which fan stage01 is switched on.

rValvePositionC_Stage02: Limit value of the control value of the cooling controller from which fan stage02 is switched on.

rValvePositionC_Stage03: Limit value of the control value of the cooling controller from which fan stage03 is switched on.

udiSecMINPowerOnTime: Minimum switch-on time that a fan must run for in a stage before switching to a different stage or switching off. Input in seconds (e.g. 120 corresponds to 120 s).

iFctModeFanCoil: The user has the possibility to activate the fan controller for heating mode or cooling mode or both modes via the valence of this variable. Valid values are 1, 2 or 3. Other values are invalid and bInvalidParameter is set to TRUE.

Cooling	Heating	Valence
0	1	1 (= fan controller active in heating mode)
1	0	2 (= fan controller active in cooling mode)
1	1	3 (= fan controller active in heating mode and cooling mode)

udiTimePeriod: Timeframe during which the manual override is active in case of presence. Specified in minutes