Voltmeter installation

[jcostantino]

I'm putting in my electric gauges this weekend. I got a good price on generic electrics so I shelved the mechanical idea.

Question is this: When I make the wiring harness for the power to the gauges, should I connect the positive wire for each gauge together and run it to my switched power and tie the grounds together and ground them to the frame? That includes the B+ for the voltmeter gauge. For the lighting I'm going to ground it to the frame and tie it into the instrument lighting.

What's the wire color at the headlight switch that I should tap into for illumination?

Jeff

 

[89 Gary]

That's how you do it. You can wire to a switch terminal which is on both the ignition on and aux on (at least the voltmeter),that way when your listening to your stereo in the "aux" position you can monitor the battery. I don't know the color because I wired straight to a terminal without dimmer control.

 

[ericwick19]

yeah tieing the power wires into one will work, but that definatley should be protected with a 30 Amp inline fuse, and attached to the accessory wire in the column, which is grey with a yellow stripe, as for the illumintation, tap into the brown wire at the headlight switch.

 

[jcostantino]

Is a 30 amp fuse too much for that circuit? I wasn't paying attention in class when they taught about calculating amp draw so I'm not 100% sure... I have a 15amp fuse that is already mounted in an inline socket, would that be OK? I don't know what sort of current the gauges draw but 30 amps seems to be high.

Jeff

 

[Dave Ladely]

yeah, 30 amps is too high, the wire would probably melt before the fuse did. All you are measuring is volts, not amps, and the meter likely only allows milliamps of current through it as you have to use a shunt, so be sure to use a shurt, which passes most of the amps, shunting only a very small portion to go through the meter; that portion is calibrated by the meter mfg. I would say a 5 amp fuse is plenty! I use a one amp fuse! The manufacturer can advise you.