Applies To:
  • CitectSCADA 5.xx

I want to read some PID block elements from an Allen Bradley PLC5, but none of the Citect drivers seem to support the following addresses:

.DFD Bit 5 Derivative Smoothing Disabled
.ZCD Bit 10 Zero Crossing Deadband Disabled
.BCD Bit 11 Bias Back Calculation Disabled

Is there anything I can do?

The Citect compiler uses the AB5.DBF file in the \Citect\Bin directory as a template to check for valid Variable Tag addresses.  There are a lot of possible combinations of PLC5 data types and addresses and not every possible address that the driver can support has been included in this template. In this case the AB5.DBF can be edited and the following 2 lines -


changed to -



If you are using MS Excel for editing, then first open the file: \Citect\Bin\Save_dbf.xls, then open the AB5.DBF file.  When you are done, right-click on any cell and choose Save/Close DBF, then quit Excel without saving.

CIT does not guarantee that drivers will work with addresses other then standard in the drivers supplied with the release version of Citect.

For more information contact Citect Support or see the Citect Driver Development Kit documentation.