How To Tune Pid For Tank Control In Rslogix 500

Hai welcome to automation world


recently i am working on MICROLOGIX 1100 i did the operation for PID block. that is one tank is there and one inlet modulating valve is there so i have to control the valve using level of the tank. i created PID block and checked in manually it is working nicely whenever it is in auto suppose if the setpoint of tanklevel exceeds the level of the tank then valve is auto matically opening suppose then we reduced the setpoint to below the tanklevel then valve is not closing still it is opening, i set the parameters are

proportional gain 1
ti 1
td 0
E = SP-PV
TIMED
YES
DEAD BAND 25
SO IF ANY ONE KNOWS THE VALUES HOW WE HAVE TO SET IN PID BLOCK FOR MICROLOGIX IN RSLOGIX 500 Immediately send to my mail id. i am eagerly waiting for your reply

thanks and regards
M.SIVA

I do not know how your valve reacts to the signal being sent to it.

Look into the following



Could it be that your E=SP-PV is incorrect



Maybe your loop is poor tuned so the integral windup is creating this reverse valve action.



When you switch to manual normally you can switch the PID block itself to manual to prevent integral windup, see Bump less transfer in help. Off my head I can’t remember it exactly.