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[normanlane]

I purchased a used BRUTUS style brew stand with SLY 2362 controllers and Honeywell furnace valves. The first time I tried it it was set for on/off control and had terrible overshoot. I would like to try PID with a relatively long cycle time to minimize the cycling of the valves. I don't know how short a time they can be on and still get a flame, but I would guess that it is on the order of a few seconds. I am using the relay output.
Is there some minimum time that the controller will close the relay, maybe as a percentage of the cycle time? If not, is there another controller that I could drop in place that would have a parameter for minimum time (or minimum % On)?
Thanks

[Kkane]

Parameter for output cycle time is OT. It is under access code 0036. For your valve, you can set it to 20s or longer.

If you still have severe overshoot, you can try auto-tune on your preferred temperature.

[normanlane]

Kkane, thanks for your reply. As I understand it OT sets the total time of the cycle, the ON time will be whatever percentage of that time as determined by the PID. So if I set OT to 20 seconds and I was very close to setpoint, the PID might command a 1% power, which would be 0.2 seconds. Is there some minimum output percentage that the PID will command, or a minimum time that a contact type output can be ON?
Thanks

[Kkane]

Unfortunately, SYL-2362 does not have this feature. SYL-2342 has OUTL parameter, which can set the minimum output percentage.

[normanlane]

I thought that there might be some intrinsic (not programmed) minimum on time OR minimum % On for the SLY 2362

[Kkane]

For SYL-2362, you cannot limit the minimum output percentage unfortunately.

You can either increase the cycle rate if you are using PID mode, or you can use ON/OFF mode instead (works like thermostat). In ON/OFF mode, the output will be either ON or OFF.