BAC_Uni_Vlv_01_xx

Functional description

The template BAC_Uni_Vlv_01_xx is used for controlling an analog control valve. It basically consists of an AO object including a trend object, an MV object for manual control, and the associated AV object for entering the manual position. The template is complemented through optional BACnet objects, see table with version overview.

The two output variables rPrVal / bSync are only active, if the valve position feedback Fdb exists in the template that is used. If this is not the case, the two versions return the value zero. The interface of the templates BAC_Uni_Vlv3P_01_xx / BAC_Uni_Vlv_01_xx is the same. For this reason, in the Project Builder in a call template a three-point valve can be replaced with an analog valve, without having to adjust the PLC code.

Versions

The template BAC_Uni_Vlv_01_xx is available in different versions.
The control valve versions are identified by means of a key. The identification key is derived from the table below.

Interface

Block diagram version BAC_Uni_Vlv_01_13

VAR_INPUT

rValPgm  : REAL; 
bEnSfty  : BOOL; 
bValSfty : BOOL; 
bEnDst   : BOOL;
bValDst  : BOOL; 

rValPgm: analog value program priority

bEnSfty: safety priority enable

rValSfty: analog value safety priority

bEnDst: disturbance priority enable

rValDst: analog value disturbance priority

bDisAblk: blocking protection function locked. Prevents simultaneous activation of the blocking protection of the pump and the control valve, e.g. at a heat exchanger

VAR_OUTPUT

rPrVal   : REAL;
bSync    : BOOL; 

rPrVal : Current position of the control valve.

bSync: Output of a pulse to synchronize the controller associated with the valve during reset from manual to automatic operation to the current valve position.
The synchronizing pulse bSync should only be used if the template used contains the valve position feedback Fdb.

VAR CONSTANT

PLT_NUM    : BYTE := 1;

PLT_NUM: all alarms and events of all plant components within a controller are included in a global alarm and event list. The assignment of events and alarms to a plant is defined by the assignment of a PLT_NUM plant number.
The recording and processing of an alarm from an aggregate or a device takes place within the templates by means of the alarm function block FB_BA_Alarm.
The evaluation of the alarms of a plant, e.g. for the generation of a collective message or for plant shutdown in case of relevant faults, takes place within the template BAC_PltAlm_01 by means of the function block FB_BA_AlarmPlt.
The evaluation of different plant events within the templates of a plant, takes place within the template BAC_PltComnMsg_01 by means of the function block FB_BA_ComnMsg.

Important! The assignment and evaluation of the alarms and events of a plant can only be done correctly if all templates of a plant have the same plant number!

The plant number can be assigned in the Project Builder in the parameter menu for the templates or via a column in the Excel import.

Program description

IO linking

Variables for linking with the terminals

Version history