cpc case controller

[dingo]

CPC CONTROLS

I have a cpc case controller which is bringing up a sensor short for all temp probes. When I reset the control, the sensors read the correct temps again and case controller works fine.
Is this due to a faulty temp probe or is the case controller playing up?
any ideas?

[andywill]

Try this
Whilst the controller is working ok put a shorting wire across 1 of the probes at the controller (dont remove any probes) and see if this brings up the same fault (all probes faulty). If yes then you have 1 probe that is playing up. If no then you have to look at replacing the controller. As you say you can reset it after the test. I have had many a probe short out before and they are usually badly fitted and burnt through on a defrost heater or snagged somewhere.
I know its a harsh method but it should let you know what you need to.

Hope it helps

[chillin out]

Sounds like a faulty controller to me.
It could also be a network 'blip'

Chillin

[TreverXJ]

What type of CPC controller are you working with? Reflex? Einstein?

[750 Valve]

I know this is an old thread but CPC make "transient resistors" to fit to their CCB's between the CCB and the probe connections, they are their to discharge any induced voltages to earth. What happens is a voltage builds up due to incorrect earthing, static electricity (most typical cause) or badly routed wiring and causes all inputs to show "short" or go crazy and read stupid temps. Mostly we find these affected cases to have the CCB's mounted under the case on or just above a vinyl floor, store RH is usually very low when these issues rear their heads as it is a static electricity build up causing the problem. We had a few sites that were a major issue and ended up getting CPC USA to come over and inspect and test - this was their finding.