Saia-Burgess Controls AG
Manual for PCD2.W745 and PCD3.W745
│
Document 26-796 E
NG06 │ 2018-10-12
Programming
Programming with PCD Classic
3
3-6
MeasRunning:
High state indicates that the data acquisition is running.
After start-up, this indicator stays low during the first sampling cycle. At the time it
goes high, all of the four input channels have an actual value which can be read out.
DiagRunning:
High state means that the sensor diagnostic is running (Overrange / Underrange /
SensorFail)
After start-up, the DiagRunning flag stays low during the first sensor fail check cycle.
When it switches to high state, all sensors are checked and the channel diagnostics
are valid.
ComRunning:
This flag becomes high when the communication to the module is ok.
Installation of the FBs
The following 3 files are necessary:
●
D2W745_B.src
●
D2W745_B.equ
●
D2W745_B.mba
Saia PG5
®
library files:
The *.src and the *.equ files should be in the Saia PG5
®
FB library:
C:\…\SBC\PG5xxx\Libs\FB\...
Module Base Address definition:
The *.mba file must be added to the Saia PG5
®
project. This file can be modified by
the user according to the number of used W745 modules and the corresponding base
addresses.
Include the FBs:
The file D2W745_B.equ must be included in the program file before the FBs can be
called:
$INCLUDE D2W745_B.equ
Use in a cyclic organisation structure
The sampling time of the PCDx.W745 module is 250 ms per channel. To achieve best
system performance, it is recommended to implement a ‘NoCommunication’ timer.
In the example in the Appendix a 100 ms timer is implemented. So the FBs Exec
and Status are executed in maximum every 100 ms. This reduces unnecessary data
transfers on the I/O Bus and improves the system performance.
