Author Topic: Fluke 87V -- residual capacitance reading  (Read 4475 times)

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Offline kff

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Fluke 87V -- residual capacitance reading
« on: July 27, 2012, 05:13:57 am »
Hi all,

A new member here.

Had a quick question about my new Fluke 87V. When in capacitance measurement mode, my meter shows residual capacitance of 0.2nF with test leads removed (auto mode). That seems a bit high -- Extech 330 is only 0.03nF by comparison. If you have this meter, can you please let me know what numbers you see?

Also -- I measure 0.20-0.25 Ohm test lead resistance. I thought this was pretty high, especially for the price. What resistance do you see with test leads connected together on your meter?

Many thanks!
 

Offline robrenz

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Re: Fluke 87V -- residual capacitance reading
« Reply #1 on: July 27, 2012, 10:08:00 am »
IMO in both cases you need to use the REL button on your meter.  That is what it is there for.  In resistance mode you are eliminating the resistance of the test leads themselves.  A $1500.00 bench meter does the same thing in 2 wire resistance mode. there is nothing wrong with your meter. In capacitance mode a set of very short leads (6") and REL will help immensely with small capacitance accuracy.

Offline Baliszoft

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Re: Fluke 87V -- residual capacitance reading
« Reply #2 on: July 27, 2012, 01:00:28 pm »
Just for reference, my u1252b reads 0.06ohms with the test leads connected together and 0.0nf with leads disconnected. 0.2 ohms is a bit on the high side in my opinion. Are your leads clean?
 

Offline robrenz

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Re: Fluke 87V -- residual capacitance reading
« Reply #3 on: July 27, 2012, 01:06:09 pm »
Lead resistance of standard fluke probes that come with the meter is .06 Ohms for the pair. So Balsizoft is correct, check your connections.

Offline M. András

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Re: Fluke 87V -- residual capacitance reading
« Reply #4 on: July 27, 2012, 03:43:31 pm »
my 289 reads 0.08x nF without leads, shorted togethers goes into overload strange it has 100mF range :) the leads are within 0.08-0.1ohms depends where i touch them together. it doest change much with the croc clips or without them
 


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