80 amp relay on 1 wire alternator
 

Has anyone used a 5 pin 80 amp relay to break the one wire alternator connection to the battery when the car ignition is Off?

I have a one wire 60 amp alternator 10si on my 59 GMC. I go 3 wire alternators now.

Re: 80 amp relay on 1 wire alternator
 

Curious what the purpose would be?

Re: 80 amp relay on 1 wire alternator
 

to kill the 35 milliamp continuous draw when ignition off

Re: 80 amp relay on 1 wire alternator
 

Is this a common problem to all one wire alts? So, is there a module (Exciter) inside the alt that pulls this small current? I've never heard this. I never liked the 1-wire I had cause of having to rev the engine once to excite it. I ended up tossing it in the trash. Went CS 130 and never looked back.

Re: 80 amp relay on 1 wire alternator
 

As I understand yes, one wires will pull .003 amps or less with alt hooked up, key off, measuring from battery negative to positive cable off battery. And that is for a good one.

I agree going forward I only get 12si's or better with 3 wires controlled with ignition switch.

I will try the relay and let you know just for grins.

Re: 80 amp relay on 1 wire alternator
 

That would take a very long time to kill a good battery for normal use though. if you let it sit more than you drive it then why not just put a trickle charger on it and call it good. Better yet go back to the 3 wire setup which is better anyway.:chevy:

Re: 80 amp relay on 1 wire alternator
 

I won't argue that, but I have a 1 wire that I will use until it dies.

Re: 80 amp relay on 1 wire alternator
 

I would only alter the wiring with relays for more important stuff like headlights or electric fans. Why not just put it on a trickle charger if the vehicle is not being used for a while? I've got the same problem BTW with a small drain that I think is coming from the newer style radio.

Re: 80 amp relay on 1 wire alternator
 

I know that some radios have memory and will have a slight draw. Same with security type items. And I do run trickle chargers. This is the only 10si I have and because the alternator has no memory to keep voltage on, I will kill it with key off. Relays are somewhat cheap.


I thank you guys for your input.

Re: 80 amp relay on 1 wire alternator
 

That is not an important draw. For BMW, which I've ben a master tech for 10 years now and the draw spec is around 40 miliamp. If you have a draw problem, it's not 35 milliamp

Re: 80 amp relay on 1 wire alternator
 

35 milliamps will draw down a battery to the point the vehicle won't crank in less than 4 weeks. (depending on reserve capacity rating)

But 35 milliamps isn't .003 amps. Which is it?

I have a one wire alternator on my boat. It came that way from the factory. I haven't noticed any parasitic drain so I haven't bothered to measure it.

Re: 80 amp relay on 1 wire alternator
 

I would say the solution is to use trickle charger on a vehicle that sits that long instead of the relay thing.

Re: 80 amp relay on 1 wire alternator
 

.003 amps or less draw is normal on a 10si 1 wire alternator with igniton off from my research