Ammeter 30-30

metalho

Well-known member
Blew my ammeter and ordered a 30 because I also purchased a 30 amp alternator. The alternator is on back order but was wondering if I can install the 30 ammeter with the original generator in place?:confused:
 
The ammeter in an A only shows BATTERY charge/discharge, not generator or alternator output. Even if you had a 200 amp alternator and a light bar with ten halogens on it, if your battery is fully charged the ammeter will say ZERO even though the alternator is putting out 200 amps.

You cannot damage a stock A ammeter even if you run thirty amps through it. The internal shunt on the stock 20A and the 30A meters is identical, only the calibration is different. The stock A wiring will, however, start smoking (think Lucas:eek:) is you run 30 amps through it for more than 10 minutes. Having a dead flat battery will draw ~25-30 Amps from an alternator for about 10 minutes then it will taper to less than 20, finally to zero when the battery is 100% charged. This will not hurt a stock ammeter.

Generator or alternator, any output rating, there is no difference if you use a 20 or 30 amp meter. The disadvantage to the 30 is it is difficult to "see" a 2 or 3 amp discharge as the needle is less sensitive.

The biggest waste of money is the big "sell" to make you think you need a larger ammeter with an alternator.
 
I have a new after market 6 volt wiring harness installed, are you saying that wont work on a 6 volt 30 amp positive ground alternator? Im confused.....
 
I have a new after market 6 volt wiring harness installed, are you saying that wont work on a 6 volt 30 amp positive ground alternator? Im confused.....

A 30 amp alt only means that it CAN put out 30 amps. It does not mean that your car will USE 30 amps at any given time.

The amp meter will show what current is flowing so unless you have equipment that will draw more than 20 amps at a time even the 30 amp meter is not needed.
 
The ammeter in an A only shows BATTERY charge/discharge, not ugenerator or alternator output. Even if you had a 200 amp alternator and a light bar with ten halogens on it, if your battery is fully charged the ammeter will say ZERO even though the alternator is putting out 200 amps.

You cannot damage a stock A ammeter even if you run thirty amps through it. The internal shunt on the stock 20A and the 30A meters is identical, only the calibration is different. The stock A wiring will, however, start smoking (think Lucas:eek:) is you run 30 amps through it for more than 10 minutes. Having a dead flat battery will draw ~25-30 Amps from an alternator for about 10 minutes then it will taper to less than 20, finally to zero when the battery is 100% charged. This will not hurt a stock ammeter.

Generator or alternator, any output rating, there is no difference if you use a 20 or 30 amp meter. The disadvantage to the 30 is it is difficult to "see" a 2 or 3 amp discharge as the needle is less sensitive.

The biggest waste of money is the big "sell" to make you think you need a larger ammeter with an alternator.

I think the biggest waste of money is the big "sell" to make you think you need an alternator. :rolleyes: If you're running a stock A the generator does just fine.
 
I also prefer the generator because its correct and because I can repair-rebuild them myself. Many find the three brush type generator confusing. The alternator costs less than a rebuilt generator and the person doesn't have to ship a core for exchange. Some think that they can get an alternator, anywhere. Actually an alternator thats converted for 6 volt positive ground and has the correct pulley isn't necessarily available just anywhere.
 
I just got a real nasty PM from pattyteddy because I said that I prefer generators. I suspect that it was mr alternator. the guy obviously has problems. I wonder if others are getting the same PM's
 
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I just got a real nasty PM from pattyteddy because I said that I prefer generators. I suspect that it was mr alternator. the guy obviously has problems. I wonder if others are getting the same PM's

Yep! I'm in the club too. I don't think he was happy with me calling out who he was and his business. What a shame, I had seriously considered buying an alternator from him on good reports of his fathers product and practices, now I wouldn't recommend him to anyone and actually do the opposite. Life is too short to be nasty to others.

Back to the ammeter discussion - I know many people who run alternators with a stock gauge with no issues. If you keep your battery in good shape you'll never go outside that anyway I would assume unless you're running sealed beams, AC, CB radio etc. with a run down battery.
 
I received two 'colorful' PM's about 20 minutes apart from the person is question.

I did as well. I envision this guy sitting in the dark thinking of new names to use to register (I have messages from several) the laughing at himself as he sends the messages thinking "that will get him, he will never know who sent it, hee hee hee". Poor pathetic soul.
 
I've currently got a 6v pos grnd alternator, thought about converting it to 12v neg grnd, bought the kit to do it (it's pretty simple). Then I posted a question on this forum and the responses changed my mind. In fact, I found a correct generator and plan to install it in the spring. The generator should work fine, as I don't plan to add accessories or halogen headlights. And- it has the benefit of getting me closer to the original. I guess I figure, what's the point of having a vintage car if it's not really vintage?
 
I've currently got a 6v pos grnd alternator, thought about converting it to 12v neg grnd, bought the kit to do it (it's pretty simple). Then I posted a question on this forum and the responses changed my mind. In fact, I found a correct generator and plan to install it in the spring. The generator should work fine, as I don't plan to add accessories or halogen headlights. And- it has the benefit of getting me closer to the original. I guess I figure, what's the point of having a vintage car if it's not really vintage?

There we go!
 
I've currently got a 6v pos grnd alternator, thought about converting it to 12v neg grnd, bought the kit to do it (it's pretty simple). Then I posted a question on this forum and the responses changed my mind. In fact, I found a correct generator and plan to install it in the spring. The generator should work fine, as I don't plan to add accessories or halogen headlights. And- it has the benefit of getting me closer to the original. I guess I figure, what's the point of having a vintage car if it's not really vintage?

Yep, I found myself with a worn out generator, and didn't think for a minute, just picked up the phone, called Berts and told them to set one aside for me.
 
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