-30 to +30 Amp meter, wiring? Options

[brer]

anyone know how these things work?
it has

+A and +B large power connections on it.

any electricians out there?

i can post a photo later tonight if needed

[lapuwali]

I suspect he means a dash gauge, not a handheld meter.

The best place for dash ammeters is on the shelf. They're generally not a good idea in a car.

The way they're supposed to work is they're placed in series between the battery and the alternator, so ALL of the charging current flows through them. They MUST be adequate for the max current, which is 55 amps on stock 914 alternator, not 30. You need BIG (like 10 gauge) wires running all the way from the alternator, up to the dash, and back to the battery. If you insist on using this, keep a fire extinguisher in the car.

Use a voltmeter instead. This will tell you if the charging system is working. It should read 12.5 v key on, engine off. 13-14 volts engine on, and 9-ish volts while cranking.