Parasitic draw test

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Neilcur
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Parasitic draw test

Post by Neilcur » Mon Mar 11, 2013 3:40 pm

Hi,

Is it normal for the amp reading to go minus 0 when using the amp clamp for this test or am i doing something wrong? i zero'd clamp before i started the capture and had it set on 20a scale

Thanks Neil

Lee
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Re: Parasitic draw test

Post by Lee » Mon Mar 11, 2013 4:00 pm

Hi Neil

Have you tried turning the Clamp around, i.e. remove it from the wire, flip it over and place it on the wire again.

it will show positive one way and negative the other.

Kind Regards

Lee :D

Neilcur
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Re: Parasitic draw test

Post by Neilcur » Mon Mar 11, 2013 4:14 pm

HI,

When i locked doors the trace went up to top of screen and then settled to 0 then after a short while went minus 2/3 amps so i took it, it was the right way round with the capture going high.

Thanks Neil

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Fat Freddy
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Re: Parasitic draw test

Post by Fat Freddy » Tue Mar 12, 2013 9:23 am

Can you post your file up?

FF

Neilcur
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Re: Parasitic draw test

Post by Neilcur » Tue Mar 12, 2013 11:02 am

I redone the test after posting the question and made sure i had clamp right way round and it was ok and is now reading ok. It must of been something i did? i removed negative lead and put a jumper cable between post and terminal and took reading of the cable. Does the length of jumper cable affect the result or not?

jez1342
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Re: Parasitic draw test

Post by jez1342 » Tue Mar 12, 2013 6:45 pm

cable length wont effect reading.
if you have to use a smaller thickness wire inbetween battery terminal and clamp make sure you dont interrupt the vehicles power supply as this may hide the fault your testing for :!:

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Autonerdz
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Re: Parasitic draw test

Post by Autonerdz » Wed Mar 13, 2013 3:43 pm

Neil,

The switch on the amp probe is rather touchy. It's easy to slide it and have it between the range detents and not realize it. This makes it behave very strangely. Make sure you have the slider switch firmly located at the selected range. Also, the battery can be low and not illuminate the low battery indicator but still cause bogus readings.
Tom Roberts
(The Picotologist)
Autonerdz

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