Modicon PID2 Loop


Thread Starter


We are looking to reduce our energy usage by placing furnace in a temperature setback mode i.e. from 1800F to 1000F. This works good however we are seeing a high current draw when going from 1000F to 1800F. The PID output is at 100%. We are considering a long ramp time to limit the output % thus reducing the current 'spikes'. This will only occur when coming out of the setback mode and go back to controlling as it normally. Does this make sense? If so is it possible? Can the PID2 block be modified to do this? Can you tell me how?

If you answer please use my business email: [email protected].
Thanks for any help.
You can develop a new logic mode, setback to normal setpoint, that ramps the setpoint from 1000F to 1800F, at the rate you want.
Therefore no new tuning is required.

Apply logic conditions for this mode such as:

-in setback mode
-setpoint = 1000F
-loop in auto

Build logic for;
-start ramp
-hold ramp
-stop ramp, quit to normal auto mode

good luck