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TheYellaBrick
02-16-2010, 06:13 PM
I am using a GM single wire alternator with internal regulator. I'm needing to wire it through the main battery switch with 2 large studs and 2 small studs. The wiring diagram that came with the switch shows running a wire from one of the small studs to (F) on the alternator and from the other small stud to the (F) on the regulator. HOWEVER with an internal regulator I can't wire it this way.

What is the proper way to wire this so that the alternator will shut down when the main switch is turned off ?
bowtie4542001
02-16-2010, 09:46 PM
Hey DD,
If I remember correctly, I believe you take a 10 gage wire from the back post of the alternator to the + side of the battery.

Chris
curtisreed
02-17-2010, 04:03 AM
Hey DD,
If I remember correctly, I believe you take a 10 gage wire from the back post of the alternator to the + side of the battery.

Chris

Through the switch. IOW from the alternator to the small post on the switch then from the other small post to the positive side of the battery. It just cuts the flow of power.

Curtis
TheYellaBrick
02-17-2010, 08:00 AM
Wouldn't that be the same as using the big posts in the same way ? That's how I have it wired now, but when I turn off the master, it does NOT kill the engine as required by most sanctioning bodies..
curtisreed
02-17-2010, 08:14 AM
You have it wired from large to large, or small to small?
johnracer
02-17-2010, 11:00 AM
Wouldn't that be the same as using the big posts in the same way ? That's how I have it wired now, but when I turn off the master, it does NOT kill the engine as required by most sanctioning bodies..
Not necessarily. Depends on which side of the cutoff the alternator is hooked to. If it's attached to the battery side or to the pos batt post, the car will shut off but the alt wire will always be hot. If it's attached to the car side, the car will continue to run because the alternator is supplying the power. By the way, when this occurs, the alternator voltage will be unregulated and will go to 20+ volts when you turn off the switch.....ever been told you could test an alternator by unhooking the positive battery cable? That's why you shouldn't. It'll supply 20+ volts to the entire car if the alternator is working......

I'd think the small posts on the switch would be independent of the big posts on that kind of switch or you could use a relay
Johnny
fla1976
02-17-2010, 01:26 PM
The easiest way is to put the wire from the alternator through a heavy duty relay. The relay is deactivated when the switch is turned off and the alternator will stop putting out current.
THERATTLER
02-17-2010, 01:39 PM
i would say hook the alternator wire to the small post that is not common to either big post in the off position
bowtie4542001
02-17-2010, 02:54 PM
Does anyone have a diagram of this. Sorry I gave some wrong info DD
TheYellaBrick
02-17-2010, 04:09 PM
No offense all, but this might be one of those 'teachable moments' that Barry is so fond of. We're getting all sorts of differing ideas here so I'm STILL in doubt as to the correct connection(not like the French Connection :shock:)
fla1976
02-17-2010, 04:25 PM
http://www.kitcarmag.com/howto/cutoff_switch_install/index.html
http://summitracing.custhelp.com/ci/fattach/get/110/1020353780
http://summitracing.custhelp.com/ci/fattach/get/111/1020354217
THERATTLER
02-17-2010, 05:27 PM
the whole idea is that the alt. wire not be hooked to batt or starter side of switch in OFF position, an ohm meter will tell you right quick which small termanal that would be...jmo
TS1955
02-18-2010, 04:05 AM
Wouldn't that be the same as using the big posts in the same way ? That's how I have it wired now, but when I turn off the master, it does NOT kill the engine as required by most sanctioning bodies..

Wire it to the big post of the switch on the SAME side your battery is cable is wired.

TS1955
suicidebomb
02-18-2010, 05:25 AM
Wouldn't that be the same as using the big posts in the same way ? That's how I have it wired now, but when I turn off the master, it does NOT kill the engine as required by most sanctioning bodies..

Wire it to the big post of the switch on the SAME side your battery is cable is wired.

TS1955

There you go, now wire the hot wire to your ignition, through the switch on the small terminals. When you turn off the switch, all electrical power is dead. Only thing I'd do different, is I'd put the Alt. wire on the opposite side of the switch, as TS1955, but his way will work fine too.
fla1976
02-18-2010, 06:01 PM
You have to break the connection to the alternator. When you disconnect the battery with the switch, the engine will stay running because it is running off the alternator. It is the same as disconnecting a battery with the engine running, the engine runs off the alternator. That is why you break the circuit to the alternator. Try it by using the battery switch and when it stays running, disconnect the alternator wire. The engine will then die.
TheYellaBrick
02-20-2010, 07:58 AM
I really appreciate all the input guys !
It is just a matter on common sense once I 'thought' about it !????????
Sometimes 'things' just don't compute as easily as they once did :shock: :shock: :oops: :oops: :oops: :oops: :oops:
ohiomafia
03-02-2010, 08:42 AM
The absolute best way to wire a one wire alternator is through a 4 post master kill switch....this reducess the number of connections (compared to using a large solenoid) and isolates all power from the vehicle. If you have a 4 post switch that has 2 large post and 2 smaller, I'll bet money that switch isn't capable of handling the amperage. If you research it...the smaller posts are only rated fro 20 amps continous. Cole Hersee 75912 is the switch needed... If you do not decide to use a 4 post...wire the alternator directly to the battery...do not terminate it to the battery side of the kill switch. The battery acts as a filter and reduces the chances of the alternator inducing noise.

Jeff Brandenburg
Dykes & Strippers
TheYellaBrick
03-02-2010, 09:20 AM
I appreciate the info !
I certainly don't have to worry about noise interference as it's a full tilt boogie race car with unrestricted 3" from collector to rear bumper. :shock:
curtisreed
03-02-2010, 10:18 AM
Welcome Jeff.
ohiomafia
03-02-2010, 02:36 PM
Welcome Jeff.

Thanks! Don't know why I never thought to look through the junks forum...LOL
TheYellaBrick
03-02-2010, 09:48 PM
Someone better scab in another seat into the 'Bus' ! We got us another newby !
Welcome aboard, Sir !
ohiomafia
03-03-2010, 06:17 AM
Someone better scab in another seat into the 'Bus' ! We got us another newby !
Welcome aboard, Sir !

Ok ok...I'm a newb! LOL I'll let this www.dykesandstripperscustomwiring.com negotiate my assigned seat on the bus! LOL
friendyomi
05-25-2010, 10:38 AM
don`t have any idea.
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