Please let me know whether Delta V system has any problems with respect to the anti reset wind up function, i heard that they have a problem can anybody confirm on this?

 

> Please let me know whether Delta V system has any problems with respect to
the anti reset wind up function, i heard that they have a problem can anybody
confirm on this?
>

- only if you don't configure the feedback signals correctly! A common configuration that is prone to wind-up is where two (or more) PID blocks are competing for a downstream element (often a valve, but could be a cascade slave PID controller) via a high or low selection block. To avoid reset wind-up, you need to use a signal downstream of the selector as the anti reset windup feedback. Provided you are careful with any scale/range issues, this works fine. "Books Online" has an example diagram somewhere which shows how to do this. I can't remember if it is clear and explicit, though - as with far too
much vendor info, many examples are too trivial, unclear or just generally unhelpful. Email me a .fhx file of the configuration you are concerned about. If I can point you in the right direction without spending a lot of time on it,
I will.

Neil Brown ([email protected])