Re: PID controller question?
Forget my previous comments as it looks like you are going about your setup a little differently than I did. I used the 6 & 7 contacts to drive a DC input SSR.
If you want to use a 120 VAC contactor such as the C25BN240A then you cannot use the SSR outputs 6 & 7.
As I stated I didn't use this type setup but the instructions (somewhat vague) seem to state that if you set 'outy' to '1' then the SSR outputs are disabled and the J2 contacts can be used to drive a relay/contactor(120 VAC).
If you want to test this I would carefully apply power to the PID, set 'outy' to '1' and meter the J2,(13 & 14) contacts to see if they are outputing 120 VAC. If so then you would use the J2 contacts to drive the contactor.
Another thing I would watch is to not use the auto tuning function. The reason I caution about this is your contactor is mechanical. So you need to change the 'ot' setting to something much larger than the default 2 seconds. This is because as the PID senses temperature nearing the set point if cycles the relay on and off rather quickly. Not a good thing for a mechanical device.
Maybe someone else has experience using this type setup?
Last edited by ed_denu; 11-04-2007 at 01:20 PM.
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