BAC_AC_VAV_01_xx

Functional description

The template is used for controlling a volume flow controller via an analog output.

Versions

The template BAC_AC_VAV_01_xxx is available in different versions.
The volume flow controller versions are identified by means of a key. The identification key is derived from the table below.

Interface

Plant diagram 01

Plant diagram 02

Block diagram version BAC_AC_VAV_01_15

VAR_INPUT

bValPgm    : BOOL;
rValPgm    : REAL;
bEnSfty    : BOOL;
bValSfty   : BOOL;
rValSfty   : REAL;
bEnDst     : BOOL;
bValDst    : BOOL;
rValDst    : REAL;

bValPgm: binary value program priority

rValPgm: analog value program priority

bEnSfty: safety priority enable

bValSfty: binary value safety priority

rValSfty: analog value safety priority

bEnDst: disturbance priority enable. This input can be used to connect process feedback, for example.

bValDst: binary value disturbance priority. This input can be used to connect process feedback, for example.

rValDst: analog value disturbance priority

VAR_OUTPUT

rPrVal   : REAL;
bSync    : BOOL; 
bForce   : BOOL;

rPrVal : Current position of the volume flow controller

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

bForce : The volume flow is under forced control from the binary output.

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