Re: multimeter question

From: Noah Little (me_at_privacy.net)
Date: 12/19/04 

Date: Sun, 19 Dec 2004 14:40:01 GMT

slight wrote:
> an example would be measuring a 10k resistor in-circuit.
> by reversing the lead polarity i get two readings, 10k and 5.8k.
> im guessing that is because the meters i have use 3.3v across the leads
> and this is triggering a diode or something in the circuit.
> are all meters like this? the ones i have are pretty cheap.
> do the flukes do this? been looking at one for Christmas.

You broke the code. Most likely reason for different readings when the
leads are reversed is a diode (or other semiconductor junction) that's
in the circuit with the resistor under test. You should find if you
lift one leg of the resistor that the readings are the same in both
directions.

Cheap meters, expensive meters, they'll behave about the same in this
regard. But you'll be happy you went with the Fluke.

Best, 

-- 
Noah

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