Wiring a voltmeter

[Greg Foster]

I have just installed an alternator in my 67 elan. The dash had an ammeter which I will be exchanging for a volt meter. What color of wire should I us to be in keeping with std. british wiring and where should I draw this wire from?
Greg

[bast0n]

Anything that is long enough to connect at both ends!

[neilsjuke]

Green = accessories via ignition switch
Neil

[Greg Foster]

Thank you Neil.
Green seemed logical but I wasn't sure if there was a tracer color related to it.

Greg

[Frank Howard]

Green = accessories via ignition switch
Neil

And black to any convenient ground.

[Mr.Gale]

Why do you want to switch to a voltmeter? The ammeter will still work with an alternator and indicate if the system is charging or not.

Mr.Gale

[robertverhey]

I have both ammeter and voltmeter fitted and must admit I find the voltmeter more useful and consult it more often. As the accessories gradually get switched on (lights, wipers, blower fan, aircon), it gives an indication whether we're still charging. Conversely, the ammeter seems to read more into the positive, the more load I place on it.....which doesn't tell me much.

[Greg Foster]

The reason I am installling the voltmeter and removing the ammeter; the P.O. had cut into the dash panel to the right and slightly higher than the center of the ash tray. The ammeter was backed tightly against the heater box under the dash. I disconnected it when I rebuilt my dash and wiring as I had the fear of the ammeter arcing against the heater box. So it wasn't operating and now I have changed to an alternator. The voltmeter looks the part, fills the hole, and actually works!
Greg

[msd1107]

An ammeter and volt meter serve two complementary purposes.

An ammeter indicates if the charging circuit is sending excess current to the battery. However, if the battery is faulty, even though it is being charged, it still may not function properly.

A volt meter can give you an advance warning of a faulty battery. Generally, you will see a depressed voltage reading on other than no load charging conditions. For instance, on switch on, idle, night time at low rpm, etc. Startup always depresses the voltage, but you will notice as the voltage decreases more during the life of the battery.

Having both instruments are best, but very few vehicles are so equipped.

David
1968 36/7988