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[LeeC]

On advice of someone with control systems experience I incorporated a contactor (w 12v coil) instead of a relay in the system I am building around a DSPR320.

What neither my advisor nor I understood was that as a PID controller the DSPR320 rapidly cycles the 12v heating contacts as the temperature probe approaches the target. The sound of the contactor acting like a six year old under influence of espresso inspired me to do a quick bit of research that indicates a contactor has a roughly 100,000 cycle life time.

My plan B is to replace the contactor either with a 120v coil contactor wired to one of the alarm terminal sets or a relay.

My plan A is to turn off or modify the PID functionality of the DSPR320. Can I either turn off the PID functionality (I am thinking I might be able to modify the 2 degree range in which the controller cycles the 12v contacts to 0 degrees) or set the cycle time to 10 to 20 seconds?

[Kkane]

You cannot use mechanical contactor with DSPR320. You have to use SSR relay.

DSPR320 is not a standard PID controller. Its AI control function cannot be turned off. Its output cycle time is dynamically changed automatically in ms level, and you cannot change it. Mechanical contactor cannot be switched that fast. Even your contactor can be switched that fast, it will be worn out in couple minutes.

For alarm output of DSPR320, yes, you can use it to drive an external contactor.

In your case, if you want to use mechanical contactor, you can consider using a standard PID controller like SYL-2342.

[LeeC]

While it wasn't the response I was hoping for it is the reply I was expecting.

Thanks for the confirmation and I appreciate the support.