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Gelbster · 04-14-2017, 11:01 AM

I am confused about the standard test we are discussing. It is unclear to me if the 68F ,0.8k to 1k Ohm test predicts a hot failure or just at 68F.
Obviously if you get zero or infinite ohms it is clear. But what is a typical reading for a CPS like yours which works fine when cold yet fails at some point with heat/heat soak?
That is why I mentioned the hairdryer .No idea if it is necessary. When you receive your replacement, you will have an excellent opportunity for a comparison test.
I did find n unverified suggestion that a sign of failure is a reading close to the lowest end of the range .Maybe if you get less than 850 Ohms, replace anyway ?

04-14-2017, 11:01 AM	#15
Gelbster Registered User Join Date: May 2014 Location: S.California Posts: 2,029	I am confused about the standard test we are discussing. It is unclear to me if the 68F ,0.8k to 1k Ohm test predicts a hot failure or just at 68F. Obviously if you get zero or infinite ohms it is clear. But what is a typical reading for a CPS like yours which works fine when cold yet fails at some point with heat/heat soak? That is why I mentioned the hairdryer .No idea if it is necessary. When you receive your replacement, you will have an excellent opportunity for a comparison test. I did find n unverified suggestion that a sign of failure is a reading close to the lowest end of the range .Maybe if you get less than 850 Ohms, replace anyway ? Last edited by Gelbster; 04-15-2017 at 04:04 PM.