Ammeter vs Voltmeter

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Marmalute
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Ammeter vs Voltmeter

Post by Marmalute »

Hi everyone
I'm looking for some input from members using their g741s.
What I'm curious about is preferences concerning ammeters vs voltmeters.
I recently acquired a fairly early M37 (within the first 800 produced) and the few wires in it would indicate that it had at some point had an ammeter in it. Hard to know for sure as the gauges and so many other parts had been "liberated" from this truck before I found it. I do know that my Ord 9 says all up to 80037413 did have ammeters.
I will eventually rewire this rig as it was originally wired, aside from adding directional lights and perhaps some auxiliary lights.
But before I go down that road, the question is: why the change from ammeter to voltmeter and functionally, who here prefers what and why?
Honestly I could make a good argument for both an ammeter and a voltmeter, but for now I'd like to keep to the 4 gauge holes and not modify the dash.
All input is greatly appreciated.
Thank you, Doug
just me
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Re: Ammeter vs Voltmeter

Post by just me »

I actually find the voltmeter to be of more use and if I had to have ONLY one that would be it. But, since I can make the choice, I have both.
The original ammeter is a shunt type meter and probably difficult to find. I chose to use an inline direct reading ammeter in mine.
"It may be ugly, but at least it is slow!"
j mccormick
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Re: Ammeter vs Voltmeter

Post by j mccormick »

With an ammeter you can see how much, how many amps, the generator is charging, and a volt meter shows that it is charging by the volts being higher than battery voltage when running. Both are acceptable, but the ammeter is more precise IMHO.

JOE
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Re: Ammeter vs Voltmeter

Post by just me »

The voltmeter is better at indicating the overall battery condition. Voltage before start, voltage drop while cranking. Voltage regulator function. Charging system condition.
An ammeter will show charging or discharging, but a sulfated battery will "look" normal on an ammeter by hard charging at start and very quickly dropping to just a bit of charge as the battery won't accept any charge.
I used to swear by ammeters, but time has made me change my mind.
"It may be ugly, but at least it is slow!"
Kaegi
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Re: Ammeter vs Voltmeter

Post by Kaegi »

I prefer ammeters as well. I cant tell instantly if I have issues or not. I can tell how low the battery is by how high the amps are reading after start up. I don't have to glare at it when driving down the road like you do with a volt meter. if there is an issue a momentary glance will tell me if discharging.
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