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https://www.autonerdz.com/cgi/yabb2/YaBB.pl General Public Area >> PicoScope >> Stray current testing https://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1268050358 Message started by Expressway on Mar 8^th, 2010 at 4:12am

Title: Stray current testing
Post by Expressway on Mar 8^th, 2010 at 4:12am

Hi, has anyone used Pico for testing cooling system stray current(voltage) with confirmed results. Everything I have always read says to use anologue voltmeter not digital. wasn't sure where that left Pico in comparison.

Title: Re: Stray current testing
Post by fisher on Mar 8^th, 2010 at 7:55am

I found
http://findarticles.com/p/articles/mi_qa3828/is_200306/ai_n9257855/
this article put out by MOTOR magazine. They dont use an analog meter. I am not sure this is what you were talking about. If it is there is nothing the PICO cant do in the way of looking for stray voltage.

Title: Re: Stray current testing
Post by Expressway on Mar 8^th, 2010 at 2:18pm

Thanks fisher, that is what I am talking about but most other information is telling me 0.05V max checked alologue against that article refering 0.3V with digital. I seem to recall the choice of meter recommended has something to do with internal impedence, could be wrong, don't really understand the electronic principles here I'm afraid.

Title: Re: Stray current testing
Post by joecar... on Mar 8^th, 2010 at 10:58pm

I believe they use a digital multimeter because it has at least 10MΩ input impedance...

An analog meter has a lot less input impedance which means it will alter the voltage you're trying to measure, especially the low voltage we're talking about here (0.3V).