Installing a voltmeter

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Fri 26 Feb 2016 12:45
Installing a voltmeter - dimdip

A voltmeter to show the general state of the battery and the charging system seems like something worth having. Not something you might want to mess about with on a newer car but useful on an older vehicle for 'health monitoring' to spot problems early.

There are 3-digit voltmeters in various colours on the bay of fees for 99p delivered to your door from the PRC which claim good accuracy, but not sure I'd believe that at face value. Also perhaps an analogue dial would be easier to take in at a glance.

Anyway, can I ask, has anyone added a voltmeter? Where abouts in the electrical system is it best to connect it? Do you need to add some kind of filtering so that the display doesn't jump around all over the place? Thanks for any tips.

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Fri 26 Feb 2016 12:55
Installing a voltmeter - RT

A voltmeter to show the general state of the battery and the charging system seems like something worth having. Not something you might want to mess about with on a newer car but useful on an older vehicle for 'health monitoring' to spot problems early.

There are 3-digit voltmeters in various colours on the bay of fees for 99p delivered to your door from the PRC which claim good accuracy, but not sure I'd believe that at face value. Also perhaps an analogue dial would be easier to take in at a glance.

Anyway, can I ask, has anyone added a voltmeter? Where abouts in the electrical system is it best to connect it? Do you need to add some kind of filtering so that the display doesn't jump around all over the place? Thanks for any tips.

Easiest way are those that plug in the lighter socket.

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Fri 26 Feb 2016 13:40
Installing a voltmeter - Wackyracer

In the past I made my own versions, one with several LED's that had a 0.5 volt diference between them and for another car a more discrete one which was just a single tricolor LED that changed colour to indicate when charging ( 13.8v upwards) or if the battery voltage was lower than 10v.

Now I use exactly was RT suggests, a cigar plug with a digital display on the end. It's the easiest, cheapest method and does not require any wiring in.

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Fri 26 Feb 2016 16:42
Installing a voltmeter - piggy

Yes,I can vouch for their usefulness.I bought one recently following a recommendation by a poster on this forum.About £1.50 on the bay of fleas.

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Fri 26 Feb 2016 21:07
Installing a voltmeter - dimdip

Thanks, I didn't know these things existed. Glad I asked as that will save a lot of faff!

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Fri 26 Feb 2016 22:29
Installing a voltmeter - Peter.N.

My C5 has one fitted, although I didn't know when I bought it. Its not calibrated in volts though just low-normal-high with coloured bands. Its very usefule for pre empting electrical problems - if you remember to look at it, you can see if your alternator has stopped working before your battery goes flat.

You can connect it to anywhere that has a 12 volt supply.

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Sat 27 Feb 2016 12:24
Installing a voltmeter - dimdip

^ Interesting that some cars still give this information at a time when the general policy seems to be to tell the driver as little as possible.

The more I think about it, the more I like Wackyracer's 3-colour LED indicator — a really neat solution. But since those cigar lighter DVMs already exist, there is no further decision to be taken :)

Edited by dimdip on 27/02/2016 at 12:25

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Sun 28 Feb 2016 18:37
Installing a voltmeter - xtrailman

I have two plugin voltmeters, very useful on new cars with smart charging, and when towing as the voltage sensitive relay used to cool the fridge relies on the voltage going high enough to pull in the VSR.

I've tested both using a proffessional volt meter, one reads 0.1 volt high, the other 0.1 volt low. Thats good enough for me.

Bought mine off Amazon for under £2 each. Use one in my car and the other in the caravan.

http://www.amazon.co.uk/Cigarette-Lighter-Voltage-Voltmeter-BuyinCoins/dp/B0092KVYGI/ref=sr_1_2?ie=UTF8&qid=1456684701&sr=8-2&keywords=plug+in+volt+meter

Edited by xtrailman on 28/02/2016 at 18:39

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