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I'm hooking up my Voltmeter in my Neg. grd BJ8 and want to know if anyone has a Wiring diagram they can post or PM me?
thanks
thanks
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Voltmeter Wiring Diagram Wanter
- Thread starter Patrick67BJ8
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Patrick--
Usually volt meters have only two contacts (not counting lighting). One goes to a positive source switched by the key and the other goes to a ground.
Usually volt meters have only two contacts (not counting lighting). One goes to a positive source switched by the key and the other goes to a ground.
OP
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Yep, I looked it up on a Hot Rod forum. I'm good. Thanks!
dklawson
Yoda
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If you have a voltmeter (not an ammeter) you shouldn't require a proper wiring diagram for hooking up the gauge.
If it's a Smiths gauge, either gauge terminal can be connected to chassis ground (preferably with a black wire), the other terminal connected via a green wire to any green wire you find behind the dash. If the gauge is a brand other than Smiths, the GND gauge terminal (perhaps a black wire) goes to chassis ground. As before, the remaining gauge terminal gets connected to any existing green wire behind the dash. Fuses are optional. If you want one, put it inline with the wire going to the car's green wire. Use something small, like 3 Amps.
Illumination can be one of two colors, red or red/white. Look for existing illumination bulbs behind the dash and splice your voltmeter's lamp wire into one of those wires.
Green wires are switched, fused wires in Lucas schemes. Connecting your voltmeter to a green wire means it will only be powered up when the ignition key is in the run position.
If you really meant ammeter, that wiring is totally different.
If it's a Smiths gauge, either gauge terminal can be connected to chassis ground (preferably with a black wire), the other terminal connected via a green wire to any green wire you find behind the dash. If the gauge is a brand other than Smiths, the GND gauge terminal (perhaps a black wire) goes to chassis ground. As before, the remaining gauge terminal gets connected to any existing green wire behind the dash. Fuses are optional. If you want one, put it inline with the wire going to the car's green wire. Use something small, like 3 Amps.
Illumination can be one of two colors, red or red/white. Look for existing illumination bulbs behind the dash and splice your voltmeter's lamp wire into one of those wires.
Green wires are switched, fused wires in Lucas schemes. Connecting your voltmeter to a green wire means it will only be powered up when the ignition key is in the run position.
If you really meant ammeter, that wiring is totally different.
Patrick,
After my recent Dynamator alternator negative ground conversion I wanted to monitor charge, but I also wanted USB device charging capability so this little device was discreetly installed. It's sufficiently accurate too. Dynamator charges (13.8V) at around 800RPM and puts out 12.8V at idele 550 - 600. GONZO.
After my recent Dynamator alternator negative ground conversion I wanted to monitor charge, but I also wanted USB device charging capability so this little device was discreetly installed. It's sufficiently accurate too. Dynamator charges (13.8V) at around 800RPM and puts out 12.8V at idele 550 - 600. GONZO.
OP
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Its a Smiths Gauge. Lighting Wiring was done to red/white as original. Black ground as original. I'm undecided as to a green wire going to the switched fuse panel or a white wire from the ignition switch. When I craw under the dash tomorrow I'll make up my mind. Console and trans out right now so I have a Board across the floorboard with comfy cushions which should make the job easier. Clock hooked up yesterday with a green/red wire. I want to think out connection of clock because I want it to run with the battery switch turned off. Heater Boost switch now provides manual electric fan operation, but I still have a parallel circuit for thermostatic control of the engine fan. (I have Austin AC system).
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Patrick,
After my recent Dynamator alternator negative ground conversion I wanted to monitor charge, but I also wanted USB device charging capability so this little device was discreetly installed. It's sufficiently accurate too. Dynamator charges (13.8V) at around 800RPM and puts out 12.8V at idele 550 - 600. GONZO.
Do you run it without the cover so you can see the voltage?
dklawson
Yoda
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The easiest way would be to run a wire from the clock to the "always hot" side of the cutoff switch.
On the Mini I have a battery cable disconnect. I have a 5 Amp fuse wired in parallel to the disconnect. That allows me to keep the low current items running with the battery "disconnected". However, if someone were to try and start the car with the battery disconnected, the 5 Amp fuse would blow. So... I still have an anti-theft disconnect while the accessories can still be powered up.
OP
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The brown wire is hot all the time unless the battery switch is off so I ruled that out. I'm thinking of running a wire to the battery as dklawson suggested. I don't want a wire unprotected or looking strange so I thought about a house thermostat type of wire, or similar, that has one or two wires in a vinyl sleeve. The clock doesn't use very much power so I'm not worried about using 16 ga wire. It'll run underneath the chassis and be secured to the battery cable with tie straps.
The dual USB charger is sealed with the two prong silicon plug, which, in the closed position, has a cut-out to view the voltmeter values. In the open position the USB ports are white and nicely contrast against black and match lettering of the heater controls. Concealed in the parcel self it works nicely for modern devices. GONZO
Randy Forbes
Yoda
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I wonder if that could be modified/adapted to just slip into the cigarette lighter...?Patrick,
After my recent Dynamator alternator negative ground conversion I wanted to monitor charge, but I also wanted USB device charging capability so this little device was discreetly installed. It's sufficiently accurate too. Dynamator charges (13.8V) at around 800RPM and puts out 12.8V at idele 550 - 600. GONZO.
OP
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I found a good website for the wiring diagrams for a Smiths Voltmeter, Ammeter & general Smiths gauges. Not a very good website when it comes to looking up things. I believe installation with the recommended 3 Amp fuses is important and I added a fuse holder in my Clock and Voltmeter gauges. I also used a Label machine and made a label strip/name for the wire as well as the fuse holder, "3 Amp". The first time I hooked up the Voltmeter I connected the hot wire to a terminal and because it was up high under the dash I couldn't see the other spade terminal and I assumed it was grounded by the case since the light worked. Well, I trouble shot it and found the other spade terminal. Works like a charm but I have to say the Voltmeter gauge doesn't make any fast movements...it's slow getting up to the voltage and you'd think it was not working unless you watched it for a while.
Healey Nut
Luke Skywalker
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Or you could just use this
https://www.ebay.com/itm/Bravo-View...481886?hash=item281440c8de:g:35YAAOSw4UtWS6pB
or any of the other gazillion other styles designs colours etc on flea bay . Most are from china so be prepared to wait for an eternity to get it in the mail if you order from china to save a few bucks .
OP
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it sure what that Gauge is. Can you post a photo?