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# CCT PID Loop tuning
7/22/20 tuning
19:30 aprox increased Ti to 75 from 60 and increased max to 85
20:05 decreased Ti to 50 from 75 after analyzing the trend. Im thinking the loop is responding a bit too slow.
21:51 dropped min% to 10 from 20 and max to 75 from 85 and added .05 Td
22:00 dropped Ti to 25 from 50 to speed up the output increase to get ahead of the rise in PV
try making the outlet orp the PV and drive the bisul with a P only loop or at least P heavy loop. The trend I see is as the "load" (cl2) increases at the outlet (shown by higher orp reads) the chemical dose has to increase substantially to keep the final orp down, but right now the loop is driving it too far
first, make sure the pid loop has anti windup enabled
would a "big" deadband help?
my guess is that the PV will not drop as low this cycle due to reducing the max output to 75.
![[CCT_PID_Loop_tuning_51ac8935096a.png]]
This turned out to be true, and it seems to have almost doubled the cyclic frequency
22:42 increased min to 25% from 10% and decreased max% to 50% from 75%
23:26 decreased min to 15% from 25% because final orp was being held down below 80
23:32 increased Td to 1.0 from 0.05 because I think it will help with boosting the rate of correction when the orp starts to ramp up due to the loading from the outlet orp just coming off it's peak