How to hook up a VDO Amps Guage?

Anthiron The Baja Rejuvenation Begins

4,936 posts · joined Oct 2003 · 29 Jun 2004, 10:53 am

#194594

picked up this baby from the cabulture markets on sunday for 5 bucks:thumb lets hope it works. i want it to measure the charge coming from my genny. do i just hook up the terminal marked "+B" to the feed wire from the regulator and earth the wire marked "+L"?

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62/60 model bug eye baja bug, (Full Build in Progress)
1974 Chevrolet Luv
1970 MK2 Ford Cortina GT
1979 Yamaha RX125 Two Stroke tracker project.
2004 Harley Davidson Sportster XL Custom

Anthiron The Baja Rejuvenation Begins

4,936 posts · joined Oct 2003 · 29 Jun 2004, 9:33 pm

#195041

bump

62/60 model bug eye baja bug, (Full Build in Progress)
1974 Chevrolet Luv
1970 MK2 Ford Cortina GT
1979 Yamaha RX125 Two Stroke tracker project.
2004 Harley Davidson Sportster XL Custom

Paul Aslanides Commited Dubber

53 posts · joined Oct 2003 · 29 Jun 2004, 11:29 pm

#195211

Do not earth your ammeter. It measures current flowing between a source of supply (Generator, Alternator) and electrical items like headlamps etc. Any leftover goes to charge the battery.

If you connect one of those terminals to earth, you'll just be short circuiting the geny/alty/ whatever you have, or the battery, depends which you connect first.

The outer case of the ammeter, and the perhaps the mounting thingo, will earth to the metal dash, thereby providing a return for the single wire which goes to the small light bulb, to illuminate the ammeter at night, if it has one. But the main circuit is not earthed - no way.

It's only the voltmeter which has one terminal earthed.

You will need a heavier cable to connect up, 5 or 6 m/m diameter at least. Plus good terminals, soldered and crimped.

But why bother ? Your charging voltage should be 13.8 at least, and that's a better guide than any ammeter, full stop.