BAC_AI_02
Functional description
The template logs an analog input value from a Bus Terminal (see I/O link) and converts it into a real process value.
The template is used so that an analog input signal (e.g. measured value) can be processed in the program as a real process value.
Interface
Block diagram
VAR_OUTPUT
rPrVal : REAL;
bHiLmt : BOOL;
bLoLmt : BOOL;
bDst : BOOL;
rPrVal: current value of the analog input object.
bHiLim: message upper limit reached.
bLoLmt: message lower limit reached.
bDst: indicates the state of the status flag "Fault" of the analog input object. Once the fault has been rectified, the message may have to be acknowledged. This depends on the parameterization of input bAckReq of the function block AlmAI.
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
Instance | Type | optional | Task |
---|---|---|---|
AI |
| Analog input object for displaying the measured value |
IO linking
Variables for linking with the terminals
Parameter | Type | optional | Process image |
|
---|---|---|---|---|
AI_Status_Measurement | USINT |
| Input | Analog input - status byte Bus Terminal |
AI_Measurement | INT |
| Input | Analog input - measured value Bus Terminal |
Version history
Version number | Comments |
---|---|
1.0.1 | First release |