Author Topic: Resistance transients  (Read 3171 times)

jon

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Resistance transients
« on: November 21, 2016, 11:39:02 PM »
I have an older MC024-010 controller which I am reading a ~4500ohm resistance on C02P08 (Ain) in temp/rheo mode.  For the most part, it reads a steady value, but intermittently the value will drop ~100ohms for a fraction of a second.  I realize that much of a swing is within the input resistance spec, but these are more like transients than just a reading that is imprecise.  I swapped the controller out with a new one and the trouble went away.  Has anyone seen this type of behavior before, why might it happen, and is there anything to be done besides trashing the controller?

Regards,
Jon

Offline Marbek_Elektronik

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Re: Resistance transients
« Reply #1 on: November 26, 2016, 10:15:10 AM »
I don't know this problem
I think, Danfoss has optimize the hardware filter?

What about software filering?

See simple filters in attachment.
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Offline bryantmorris

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Re: Resistance transients
« Reply #2 on: January 03, 2017, 11:55:52 AM »
Could be a faulty controller rather then a problem with the model. Sounds like you have done the right thing by swapping it out.

Offline Marbek_Elektronik

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Re: Resistance transients
« Reply #3 on: January 14, 2017, 10:30:38 AM »
What is the distance resistor to controller ?
And are there any cables in parallel, switching inductive loads?
Marbek Elektronik, Dipl.-Ing. Bernd Konrad
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