Problems with Allen-Bradley PID modules?
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This post was last edited by Hardmen on 2010-7-3 at 14:00. The function of the Allen-Bradley PID module in the program is to regulate the steam flow to the reactor. The condition for the TS switch to activate is that the liquid level should be below 0.5 meters, at which point the steam valve should be closed. However, once the program is installed in the controller and the conditions on-site are met, so that the TS condition is satisfied, the PID module still does not produce any output. Why is that?
This post was last edited by Hardmen on 2010-7-3 at 14:29. Try switching the PID operation mode from RM to manual tracking when the liquid level is below 0.5, with the tracking setpoint TP set to 0
tS is prioritized. Have you set the tracking value for tp? If TS is true, out tracks tp!
The correct answer is on the 2nd floor: it’s necessary to first set RM=0 and the tracking value TP=0
I wonder if your problem has been solved? I know that in some systems, when there are alarms due to parameter exceeding limits or during tracking output, there is a parameter called alarm deadband or tracking deadband (I can’t remember the exact name). You can check to see if such a parameter exists; if it does, set it to zero. It’s just a suggestion; if it’s not the right issue, then I’m just overstepping my bounds. :lol