While chasing electrical demons on my 52 1/2 ton with a 12v conversion, I hooked up the ammeter according to the diagram in Chevrolet Truck Shop Manual and the gauge worked backwards. Meaning without running, pulling on the headlight switch showed positive (charge) and after starting, the gauge would go negative (discharge). The diagram shows the battery positive is connected to the positive side of the ammeter and the alternator is connected to the negative side. I checked voltage at the alternator and it was 14.1 volts.
I looked for a generic diagram on the internet for hooking up a ammeter and it shows the opposite. The battery positive goes the the negative terminal of the ammeter and the alternator goes the positive side of the ammeter.
I swapped the wires and it seems to function correctly. Has anybody else noticed this or am I totally wrong?
Last edited by Phak1; Fri May 10 2019 01:05 AM. Reason: Grammar