The CJ3A Page

Author Topic: Volt Gauge or Amp Gauge  (Read 4122 times)

0 Members and 1 Guest are viewing this topic.

Offline Tumbleweed

Volt Gauge or Amp Gauge
« on: January 06, 2015, 10:34:38 AM »
When converting to 12V alternator is it necessary to change the amp guage to a volt guage? Reason I ask is that I read somewhere that you have to reverse the connections on the amp guage so it reads properly when charging - and I already purchased the amp guage. I have given up looking for a 12V generator at a reasonable price.


49 CJ3A - "Smokey"
53 Willys Wagon - "Wylie"

Offline Bob W

Re: Volt Gauge or Amp Gauge
« Reply #1 on: January 06, 2015, 03:35:14 PM »
No need to change the amp gauge to a volt gauge. It all works the same way on 6 or 12 volts. The only issue you need to consider is that the alternator output could be higher than the maximum ammeter capacity. Then you would need a different ammeter to handle the higher current.
Bob W

Offline Mark W.

Re: Volt Gauge or Amp Gauge
« Reply #2 on: January 07, 2015, 01:39:41 AM »
Amp meter with a Generator

Volt meter with an Alternator

Will give you the most useful info on what the unit is doing.

You will never see an amp meter in vehicle that came stock with an Alternator.
Chug A Lug

1948 CJ2A Tub and Title
1949 CJ3A Windshield
1957 CJ5� �Frame and Springs
134L T90 9.25" D18 D25 and D44 30 spline
11" Brakes, Saginaw Steering, 12V electrical
currently in a zillion pi

Offline Julian

  • Project Jeep (Newbie)
  • *
  • Posts: 10
  • Total likes: 0
  • Karma: +0/-0
  • Still Plays With Jeeps
    • View Profile
Re: Volt Gauge or Amp Gauge
« Reply #3 on: May 20, 2015, 03:36:12 AM »
Vehicles with Alternators did sometimes come with ammeters, AMC were doing this into the 80s. They are just showing the battery circuit is charging, which is a little bit hit or miss with generators.

Whether or not you want to keep it is debatable, the way it is wired is to take the power cable into the meter and out the other side. In a short circuit under the instrument panel this makes full battery power available to the fire and puuuuf.

Voltmeters can be wired a lot more safely and are just as informative.

Offline aboyandhisdog

Re: Volt Gauge or Amp Gauge
« Reply #4 on: August 24, 2015, 01:48:06 PM »
I just stumbled on this yesterday and found it an interesting comment on this issue: