Parasitic Draw Testing - New To Me

Technical information and Q&A applicable to all years and models of Goldwings
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Parasitic Draw Testing - New To Me

Post by Bluewaterhooker0 » Fri Sep 22, 2017 10:26 pm

I came across this YouTube video a couple of days ago, and thought some folks here might find it as interesting as I did. I've never heard of such a thing.
They don't explain the methodology too well, but as near as I can determine, everything conductor has resistance, and someone has gone to the trouble of determining the exact resistance of common fuses. With that known, measuring the voltage drop across any given fuse (mv) can provide an extrapolation of the current passing through that circuit. The benefit, as explained in the video, is that neither the fuse being removed, nor the circuit being broken, is needed in order to determine the current passing through the circuit. Pretty neat. There are charts that accompany different types of fuses. I am posting the video, a link to the downloadable .pdf file charts, and a portion of the chart most common for the Goldwing.
Enjoy !

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Re: Parasitic Draw Testing - New To Me

Post by Swagonmaster » Sat Sep 23, 2017 1:07 pm

I have seen the same information from a different sources but it is similar. It's most valuable when the expected current draw is known so you can differentiate between a device that won't turn off and a short circuit but this will definitely tell you that something is drawing juice.

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Re: Parasitic Draw Testing - New To Me

Post by topgun » Sat Sep 23, 2017 8:21 pm

That "someone " would be the manufacturer of fuses. Fuses have some resistance and therefore also a voltage drop.
Resistance causes heat, and when the circuit causes enough heating to equal the rating, the fuse element
melts or as we like to say "blows".

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Re: Parasitic Draw Testing - New To Me

Post by ekvh » Sun Sep 24, 2017 4:27 pm

Neat, thanks for sharing.

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