Author Topic: amp gauge  (Read 1249 times)

69RSZEE28

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amp gauge
« on: December 18, 2013, 03:55:14 AM »
How do I test the amp gauge for 69 out of the car?

69Z28-RS

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Re: amp gauge
« Reply #1 on: December 18, 2013, 01:47:48 PM »
From what's been said, it seems a very small dc voltage would engage it.   (a 1.5 vdc battery with a pot across it to allow adjusting the pot output from 0Vdc toa few millivolts?)..  (D'Arsonval movements are very sensitive to very small voltages)
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe, '70 Mach I 
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan

Ed_B

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Re: amp gauge
« Reply #2 on: December 18, 2013, 03:17:18 PM »
To test the amp gauge connect a partially dead AA battery (+ on pin 3 and - on pin 4), it should register 40 amps charge (depending on condition of battery), reverse the AA battery and it should register 40 amps discharge. I got one of these at Radio Shack for a few bucks just for this purpose (see below).

I recommend you don't use a new battery since it'll be 1.5VDC. The one I have I got out of my Cable TV remote when it wouldn't work anymore! It read just under 1 volt. Also, don't leave it attached for too long. Just long enough to see the needle deflect both ways.

Ed
« Last Edit: December 18, 2013, 06:44:15 PM by Ed Bertrand »

Mark

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Re: amp gauge
« Reply #3 on: December 18, 2013, 06:23:46 PM »
Be carefull, full scale deflection on the gauge is about 0.5V (0.5V will make it read full scale one way or the other)  Don't try it with 1 12V source unless you like buying new things.
Mark C.
1969 Indy Pace Car
350/300HP RPO Z11

69Z28-RS

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Re: amp gauge
« Reply #4 on: December 18, 2013, 08:24:55 PM »
If you hook a potentiometer across a 1.5 V battery, and adjust the pot to the LOW end, you will be at 0 volts.. and the ammeter across from the low side of the battery to the mid point, then you can slowly adjust the voltage on the ammeter until you read full deflection (and you could then measure that voltage with a meter)...   and by flipping the battery leads, you can check deflection in the opposite direction.
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe, '70 Mach I 
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan