Help needed on setting one of these up and tuning it to the process... This will be a first time for me. There must be someone who can help out here... It would be appreciated. Process control is new to me.
You must put your process in steady-state oscillation and observe the process variable on the pCon strip chart. To perform the closed-loop tuning procedure, complete the following steps:
1. With the controller in automatic mode, carefully increase the proportional gain (Kc) in small steps. Disturb the loop after each step by making a small change in the setpoint. The process variable should start oscillating as you increase the Kc. Keep making changes until the oscillation is perfectly sustained, neither growing nor decaying over time.
2. Record the controller proportional band as (PBu) as a percent, where PBu = 100 / Kc.
3. Record the period of oscillation as (Tu) in minutes.
4. Multiply the measured values by the factors shown in the following table, and enter the new tuning parameters into your controller. The table provides the proper values for a quarter-decay ratio.
If you want less overshoot, reduce the gain Kc.
Controller....PB (percent)...........Reset(minutes)...........Rate (minutes)
P.................2.00 x PBu
PI................2.22 x PBu..............0.83 x Tu
PID..............1.67 x PBu..............0.50 x Tu...................0.125 x Tu
Note Proportional gain (Kc) is related to proportional band (PB) as Kc = 100 / PB.
