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09-13-2020, 02:08 PM | #1 |
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Digital Voltmeter Wiring
I ran across a digital voltmeter in a old tool box. I don't remember where it came from. I put the red and black wires across a battery, and it works! Even flashes on and off under 12V. So I think im going to install it in my car.Here's my question. There is also a purple wire on it. What could that be for?
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09-13-2020, 02:29 PM | #2 |
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Re: Digital Voltmeter Wiring
It’s likely lighting.
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09-13-2020, 05:30 PM | #3 |
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Re: Digital Voltmeter Wiring
It IS lighting. But not backlighting since it is digital. So when there is no power on the purple wire, the display is bright . When power is on the purple wire,the display dims.
My car has no master cut off switch and I normally do not disconnect the battery, the gauge will display forever, so I hope the parasitic draw is tiny. |
09-13-2020, 06:48 PM | #4 |
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Re: Digital Voltmeter Wiring
If you have msd ignition, they live a lot longer if you disconnect the battery at night and after you leave the track.
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09-13-2020, 06:52 PM | #5 |
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Re: Digital Voltmeter Wiring
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09-13-2020, 09:35 PM | #6 |
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Re: Digital Voltmeter Wiring
Everett, the purple is to dim it, if I’m remembering the ones I had before, correctly. I just capped them, with a crimp end.
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09-13-2020, 09:49 PM | #7 |
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Re: Digital Voltmeter Wiring
Kenny..now I remember where that gauge came from..It was in that center console in the Cutlass!..along with 16 miles of wiring LOL. I found a new home for it.
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09-14-2020, 11:46 AM | #8 |
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Re: Digital Voltmeter Wiring
the purple wire is an option to dim the display when the lights are on. You can connect the purple wire to a tail light or park light on wire.
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09-14-2020, 01:04 PM | #9 | |
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Re: Digital Voltmeter Wiring
Quote:
Dan
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Dan Foley SC 4698 |
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