5 replies to this topic

[Protarmic]

Would you guys help me out with wiring in an amp gauge? I dont think it truely serves a meaningful purpose but my car came with one so id like it to work!

[Tomf]

i wouldnt advise you to wire it in because if there is and problems it just causes fires as you cant use a fuse

[Bounce]

who says you cant use a fuze!?!?

As an Ammeter needs to be wired in in series into a circuit. If you wire it into your main battery cable, it'll only tell you what the battery is getting as a charge/discharge.

If you decide you want to know what the whole car is taking, youll have to get some good, thick wire, cut the two thick wires coming off your alternator, splice some of your wire in, run it up into your dash (routing if the wires is important, make sure they dont chafe on or get in the way of anything. Else you could get a massive short to earth) put that into one side of your Ammeter. Put another piece of your wire on the other side of the meter and run back down to the other end of the cut alternator wires. Just make sure the Ammeter can take 75A

Alot of fapping around if im honest, why not just stick with a volt meter?

[Protarmic]

who says you cant use a fuze!?!?

As an Ammeter needs to be wired in in series into a circuit. If you wire it into your main battery cable, it'll only tell you what the battery is getting as a charge/discharge.

If you decide you want to know what the whole car is taking, youll have to get some good, thick wire, cut the two thick wires coming off your alternator, splice some of your wire in, run it up into your dash (routing if the wires is important, make sure they dont chafe on or get in the way of anything. Else you could get a massive short to earth) put that into one side of your Ammeter. Put another piece of your wire on the other side of the meter and run back down to the other end of the cut alternator wires. Just make sure the Ammeter can take 75A

Alot of fapping around if im honest, why not just stick with a volt meter?

Heh. Well i might just leave it dead then. Its these 3 little chrome gauges that came in the dash but they arent wired in! i have the oil pressure wired in though... Then theres some other thing. Don remember if its oil temp or something else!

Thanks anyway!

[Dan]

Well that's one of the problems. The biggest commonly available ammeter for a car is 60 amps. And you have an awful lot of power running through those cables into the dash and back again, lots of chance for a big fat short to earth through a large gauge cable. If you fit it with a fuse and it blows, you instantly loose all power in the car (if it's fitted right). If the gauge fails you also instantly loose all power in the car. Including the ignition, brake lights and hazards lights. to be honest an ammeter isn't worth the hassle in a car that runs an alternator (as opposed to a car that runs a dynamo). I think that some ammeters (VDO I think) have a remote shunt so that all the heavy current stays in the engine bay and away from the dash, but if you don't have one of that type then they are a pain.

[dklawson]

If you must have an ammeter then buy a shunt type as Dan suggests. If you're only doing this to use the 3-gauge set you bought... I wouldn't bother. Replace the ammeter with a similar looking volt-meter.

A brief explanation of a shunt type ammeter is that you put the shunt (which is a large, low resistance, resistor) in series with the main power lines just like you would a traditional ammeter. The current flowing through the shunt creates a small voltage drop. The ammeter gauge mounted in the passenger compartment is actually a very precise and delicate volt-meter which monitors the drop across the shunt. In effect, you're wiring a relatively safe volt-meter inside the car.