Lotus Elan

What have I done this time?

PostPost by: gav » Sat Aug 29, 2015 2:03 pm

Many moons ago I replaced my wiring loom and had it checked out by an auto electrician. He adjusted the wiring so that I could run an alternator.
The car has been running fine ever since and all of the electrics are working fine - However - I was worried about the battery life and put a volt meter between the battery cable (by the solenoid) and earth and found that the alternator is providing a negative voltage.
I reversed the wiring on the gauge and it produces 12.5 volts

What on Earth have I done (pun intended)

Any clues would be gratefully appreciated as am clueless on electrics.

Many thanks in advance
Gavin
One day I'll actually finish - completely - one day....
User avatar
gav
Third Gear
Third Gear
 
Posts: 466
Joined: 26 Jan 2004
Location: Hertfordshire UK

PostPost by: bob_rich » Sat Aug 29, 2015 2:14 pm

Hi Gavin

If everything is working fine then you dont really have a problem. The volt meter reading at 12.5V ( irrespective of which polarity you connect it) is correct in value I suspect that it is simply a case that the +ve and -ve terminals are swapped over so the polarity appears wrong.

regards

Bob
bob_rich
Fourth Gear
Fourth Gear
 
Posts: 564
Joined: 06 Aug 2009

PostPost by: gav » Sat Aug 29, 2015 2:31 pm

Hi Bob

Just been out to check again. It is possible that I misread the wiring positions on the gauge - without the engine running and the gauge correctly wired up (!), I have 13.5 volts with no electrics running.

I'll check it again with the engine running but this might just be a case of me needing new glasses !

Heres hoping.

Thanks
Gavin
One day I'll actually finish - completely - one day....
User avatar
gav
Third Gear
Third Gear
 
Posts: 466
Joined: 26 Jan 2004
Location: Hertfordshire UK

PostPost by: billwill » Sat Aug 29, 2015 6:02 pm

If the Alternator really was producing the voltage the wrong-way around I think you would have seen lots of smoke.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4724
Joined: 19 Apr 2008
Location: London UK

Total Online:

Users browsing this forum: No registered users and 11 guests