Ammeter positive and negative

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Jan 24, 2004 | 02:54 PM

1968stepside

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From: Tucson, Arizona

Ammeter positive and negative

Just want to double check with you guys. Far as I can tell, as you are facing the back of the ammeter (original) the post on the right is the negative and the post on the left is the positive. Please correct me if I'm wrong. I am a few connections away from getting to begin testing my connections!!!!!!

Jan 24, 2004 | 02:58 PM

Mike W

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From: Central Kali

If the alternator is charging ok, but the ammeter shows a discharge, reverse the connections.

Jan 24, 2004 | 03:11 PM

1968stepside

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Ok, thanks!

Jan 24, 2004 | 04:05 PM

billemc

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I hope you are talking about a volt meter, the amp meter goes in series with the charging system or between the alt. and the battery. If it is an ampmeter and you hook one side to ground some exciting things will happen just before the amp meter burns up. A volt meter will probable read from 8 to 18 volts. An ampmeter will probable read -30 to +30 and the needle will be in the middle when there is no current drain. Hope this helps

Jan 24, 2004 | 08:07 PM

1968stepside

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I am talking about the original factory ammeter. I figured it out with my wiring diagram. Thanks

Apr 17, 2004 | 05:27 PM

1968stepside

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Well, I smoked the original gauge. It seemed to be working fine until I got a little carried away. I was testing the new harness using a 10amp setting from a battery charger, just like the Painless directions said to. I pulled on the lights a few times. Then tried the turn signals, no problems. Brake lights were next, good to go. Then I hit them all at once. The overwhelming smell of smoke disturbed me. I looked in the cab and saw it coming from the ammeter. The needle was pegged to the "C" (right) on the gauge. So, did I have the wires the wrong way like billemc said? It didn't do that when I only had one switch on at a time.

Please let me know. I want to go buy a voltmeter shortly if that would be better and since my original gauge is done.

Bryan

Apr 17, 2004 | 07:46 PM

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From: Brea CA

Yeah an ammeter has a plus and a minus side for polarity or in other words the direction of the current.

I'm not familiar with the painless harness but do they want an ammeter or a voltmeter there?

Also how thick are the painless wires that run to the ammeter (or voltmeter)? My guess is if they are thick (and they want a ammeter) then they wanted an ammeter with a built-in shunt. The original ammeter has a remote shunt in the harness under the hood, that's why the factory wiring is thin to the gauge, it carries a very small fraction of the actual charging current. If so, you pumped a hell of a lot of current through the stock gauge and let all the smoke out.