AMP Gauge upgrade?

MR nova @#25

Petty Officer 2nd Class
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Dec 7, 2011
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I'm doing a total restoration on a 35 year old boat, to include all gauges. My question is. Can I replace the old Amp gauge with a volt gauge?
 

dingbat

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Re: AMP Gauge upgrade?

It certainly can be done. Just needs to be wired into the system differently than a voltmeter.
 

alldodge

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Re: AMP Gauge upgrade?

I'm doing a total restoration on a 35 year old boat, to include all gauges. My question is. Can I replace the old Amp gauge with a volt gauge?

Yes - That being said the amp meter uses an internal or external shunt to allow the current to be measured. The link below shows an external shunt and how it works.

Ammeter Shunt - 1964 Nova SS - 1964 Chevelle SS

To connect a volt meter, connect the two wires together without the shunt. Attach a third lead to the wires just put together. Run the third wire to the positive side of the voltmeter. Connect another wire to the negative side of the meter to ground.
 

wrench 3

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Re: AMP Gauge upgrade?

Unless you are installing a high impedance digital meter, you will want to connect the volt meter to the ignition side of your key switch, so it doesn't run the battery down when the engine is off.
 

alldodge

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Re: AMP Gauge upgrade?

Unless you are installing a high impedance digital meter, you will want to connect the volt meter to the ignition side of your key switch, so it doesn't run the battery down when the engine is off.

Very good point and I missed that entirely, glad you caught it. My method would work but the voltmeter would be on all the time. Best to run the positive off the key switch
 

bruceb58

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Re: AMP Gauge upgrade?

The wires that run all the way to the dash need to be located near the engine and connected together. Then a gauge can be installed at the helm connected to the ignition switch , ground and to the nav kights if its a lighted gauge.

Even digital gauges can drain a battery so they need to be on the ignition switch as well.
 

jhebert

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Re: AMP Gauge upgrade?

I'd just get a BATT GAUGE for your GPS and connect it with NEMA.
 

wrench 3

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Re: AMP Gauge upgrade?

The wires that run all the way to the dash need to be located near the engine and connected together. Then a gauge can be installed at the helm connected to the ignition switch , ground and to the nav kights if its a lighted gauge.

The wires to the ammeter may also be running some of your other electrics. If you join the wires at the dash the system will work just as well as it did with the old gauge in the system. And you won't have to rip your wiring harnesses apart.
 

sam am I

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Re: AMP Gauge upgrade?

the wires to the ammeter may also be running some of your other electrics. If you join the wires at the dash the system will work just as well as it did with the old gauge in the system. And you won't have to rip your wiring harnesses apart.




Bouncymeter.gifA to V.jpgvoltmeter (1).gif
 
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bruceb58

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Re: AMP Gauge upgrade?

The wires to the ammeter may also be running some of your other electrics. If you join the wires at the dash the system will work just as well as it did with the old gauge in the system. And you won't have to rip your wiring harnesses apart.
Yes, that's probably true but might be better to use the wire that runs to the ammeter to power up the fuse panel.
 

sam am I

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Re: AMP Gauge upgrade?

I kinda did too, gave a sorta sense of getting from here to there in a weird and twisted way, A to B if you will.

e.gif

I wiped the links to them in wrenches quote though......keep things clear for OP
 
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