FE-FC Holden Discussion Forum

Hello,
       I've got a Wilsonia gauge and a 55 amp alternator in the ute.

What's the best wiring set up for the amp gauge in the situation?

Thanks in advance.

Regards, Wasim

I'm "borrowing" from the HD X2 wiring diagram here:

From the ammeter "G" (or positive) terminal, run two fat red wires, one to the alternator B+ terminal, and the second to the main supply terminal of the fuse panel.

From the ammeter "B" (or negative) terminal, run one fat red wire to the big terminal on the starter solenoid where the battery (+) cable connects.

"Fat red wire" means 10 gauge, at a guess 2-1/2 or 3 sq. mm.  They have to carry the alternator's full output (55 A).

Beware:  This circuit is not fused, and has a high current capacity.  If things go wrong, they will go very wrong, very quickly.

Rob

Thank you once again Rob - I’ll try and fit a fuse in somewhere?

I’ll tackle almost everything on the car with some confidence - but with electrics I’m very wary - some might say get an auto electrician - but that defeats the purpose of having the satisfaction of doing it yourself.

That reminds me - need to find an accessible place for an extinguisher 😂😂😂

Cheers, Wasim

Hi Wasim, are you committed to an ammeter? Voltage guage is much safer and provides useful info. Putting a fuse between alternator and battery runs the risk of damaging the alternator if it blows while charging. With a voltmeter you can fuse all the other circuits with a main fuse, but keep a direct unfused cable between battery and alternator. Modern high output alternators are well beyond the range of common ammeters as well.
If you are running a generator there are no dramas fusing the feed or risk of outgrowing an ammeter😀.

Sent from my SM-G975F using Tapatalk

He's using a Wilsonia gauge set, so he is stuck with an ammeter.

Don't use a regular fuse in the 12V supply wire, use a fusible link or a bolt-in type fuse like a Midi or similar.

See here:- https://jaydeeautocables.com.au/products/midi-fuse-holder

Dr Terry

Here's the wiring diagram I used:





(That's right, no wires at all.)
I've got a regular Wilsonia gauge in my FE. I'm rather fond of the car, so I didn't connect the ammeter. Like Rob said, there's a lot of current carried on that wire. All you need is for where it passes through the firewall to wear through the insulation, or discover the hard way it's been getting caught in one of the pedal return springs, or just come loose off the connection, and you'll have a very nasty situation.

Just admire its looks, and treat the ammeter as purely decorative, is my advice.

cheers
RET

I concur.

Dr Terry

Thank you for all the replies, suggestions and cautions.

Regards, Wasim

 Settle down guys! I purchased a heap of these gauges @ a clearance sale when I started my restorations back in the eighties. The ammeter section is connected in series into the loom. there is a cutout in the firewall grommet to accommodate the wire feed. The problem you may encounter, is the extra current supplied, should you fit a red motor, or an alternator, rather than a the intended gennie. Any problems I had over time were associated with the oil feed from the block to the gauge. The brass fittings need to be kept firm. I have fitted these gauges to most of my restos with no issues. Google the correct fitting instructions & enjoy with confidence. Kevin. ;)

Have to say I've been running the Wilsonia guage set in a few cars for some time now
Only issue was a slight oil leak in one of them at the guage

No issues apart from that as yet but mine are on grey not red motors all with generators

I have installation instructions somewhere so will post when found

Alex  posted  a feature on a 50 amp version in Accesory of the week, perhaps that model might be more suited to an alternator