Thread: 34970A/34901A: Thermistors: is there a limit


Permlink Replies: 1 - Pages: 1 - Last Post: Oct 13, 2011 2:38 PM Last Post By: lhornburg
nmgdcrpjq

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34970A/34901A: Thermistors: is there a limit
Posted: Oct 13, 2011 1:57 PM
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We are using an 34970A/34901A unit with BenchLink Datalogger 3 to simultaneously track several temperature readings. When we hook-up just five thermistors, we get reasonable readings. When we add a sixth thermistor, our hot water temperature readings jump by 10-15C and our room temperature readings jump by 20-25C. We have substituted other thermistors for the sixth thermistor and we still get this phenomena.

Is five the limit for two-wire, 10K thermistors? Are the channels we are using having an effect? For six thermistors we use channels 209, 211, 213, 215, 217 and 219. For five thermistors, we omit channel 219.

Bert Stunkard, University of Illinois
lhornburg

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Registered: 01/15/10
Re: 34970A/34901A: Thermistors: is there a limit
Posted: Oct 13, 2011 2:38 PM   in response to: nmgdcrpjq in response to: nmgdcrpjq
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There is no limit to the number of thermistor channels on the 34901A. This sounds like the 6th channel (219) may be stuck closed. I suggest trying another channel or another 34901A.

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