Amp Meter Question

I'm putting my dash back together and I want to hook my gauge up correctly. The two gauge terminals are marked with a + and a - . I have a wire from the positive side of the battery and another wire going to the alternator. Which wire goes to which terminal? I blindly unhooked them so I haven't a clue and I don't want to pull the dash again to switch them around. I bow to the experts in advance.

 

i know this reply isn't answering your question, but i'd recommend using a voltmeter instead of an ammeter. theres a lot of discussion on the web about this. here's a quick overview....

http://www.egauges.com/ATM_Tips.asp?TipPage=voltmeterammeter.htm

 

Voltmeter definitely sounds safer - I hadn't thought about changing to one (or know the reason why). I think I will switch. Thanks Linckeil for the info link.

 

I switched to a volt meter a while ago. Now i'm thinking about using n amp gauge also. The volt meter tells you about the condition of your battery, but nothing about your alternator. At least that's how i understand it. You could have a reading of 13 - 14.5 volts but have next to no amperage. If your alternator starts to go it will still put out voltage, just no amperage. I think

 

An amp meter is hooked in series where a volt meter is hooked in parallel.

Basically, the current runs thru an ampmeter. So you would hook one end of the red side (+) to the amp meter, then the other end of the wire goes to the alternator. You are basically breaking the feed from the alternator to the battery. A word of caution on Amp meters, they are only rated for a 60 amp swing. Now, if you are running a winch, all your lights, motor, and any other goodies, you are pulling some serious amps. My alternator is rated for 150 amps and a mean green alternator is rated for 200 amps. I am running dual batteries so I can pull some serious power with that much juice, your amp meter is rated for 60 amps, in tunrn, you smoke the amp meter, it breaks the feed to your alternator and battery, and bingo, you are dead on the side of the road. I use an alternator to monitor my electric fans because it lets me know if one of the fan motors is starting to let go.

A volt meter is in parallei. This means the (+) goes to the red side of the battery and the negative goes to the (-) side fo your battery. It is monitoring the output of your voltage. Basic electrical theory, or OHMS law.

E=IR or voltage=current x resistance. This means when your alternator kicks in to charge your battery it will put out about 14 volts while charging and drop down to 12 volts just siting idle.

In short, go with the volt meter.

My two cents, take it for what its worth.

Dana

 

Sweet diamond plated dash!!

 

:iagree:

 

I used a voltmeter this time around instead of the amp meter. My jeep had had a fire under the dash at one time from the amp meter. So long as your voltmeter shows an output of around 14 volts when the engine is running your battery is charged.