All electric meters measure current flow (amps). A volt meter is measuring
the current flow through a known resistance and is calibrated to display the
voltage based on the current flow through that known resistance.
A fuel gauge measures current flow through a variable resistance that
changes as the float in the tank moves up and down (the fuel gauge assumes a
known and stable voltage).
So to convert an ammeter to a voltmeter you need to determine what
resistance needs to be placed in the circuit to calibrate the meter to the
volt scale you come up with. The math is fairly simple, but I don't know
some of the constants involved, so I'm not going to try it today. It is
something I plan to do on mine, unless I buy new gauges instead.
Testing a fuel gauge would should be easy too. You'd need a 6-volt power
source, and a variable resistance that is similar to the sending unit in the
tank. I don't know the specs of the sending unit, but I bet someone on this
list has a pretty good idea. I don't know if it should read full or empty
when the resistance in high or low. But if it were me I'd try it with some
turnsignal type bulbs as my resistors to see if the gauge moves. It is
moves it probably works.
But you should know what smoked the first gauge before putting in another...
If you haven't corrected the problem you are likely to smoke the second too.
----- Original Message -----
From: "Paul Moon" <capt2th@tehama.net>
To: "Oletrucks" <oletrucks@autox.team.net>
Sent: Thursday, April 10, 2003 7:24 AM
Subject: [oletrucks] amps to volts
Placed an alternator in the truck, but my dash guages (which I want to look
original) read the amps instead of volts. Is there a hidden way to alter
the
incoming to have the ampmeter read volts. Heard there was. Anyone have any
info?
Thanks,
Paul Moon of Red Bluff, CA with the 55 2nd series almost done
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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