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Stroker
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5,458 Posts
Discussion Starter · #1 ·
Hi,

got a 1 wire alternator to wire up, googled it and discovered that they don't have a 'dash light' igntion on facility!?

Is that right?
I got the alt by default, so will have to get over the dash light glitch.
I do have an ammeter dial in car so will have an idea of charge etc.
So does that mean I have to run the charging wire from the alt thru the ammeter then to starter?

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I do have the instructions with a single wire kit and it suggests one maxi fused lead to the starter and one to the fuse box!?
Dunno about the fuse box lead as there's a main feed going there from the the starter anyway (batteries in the boot).

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Also, I do have three relays to feed under the bonnet so trying to find an insulated terminal like this to avoid too many wires lashed onto starter.



Had a swatch at Premier and CBS but struck out :cry: Any ideas?

Cheers!
KJ
first of many sparky questions to come! :wave:
 

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I'm Not Jed Clampett
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2,725 Posts
One wire alternators don't have a warning light 'cos the current to excite the field comes from the one wire.
 

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drag race addict
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1,392 Posts
One wire alternators don't have a warning light 'cos the current to excite the field comes from the one wire.
eau contraire...:D
They do need a warning light. You need a bulb with two connectors.Ign switched 12v to one side of the bulb,and the other side to the terminal on the alternator..:tup:
 

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I'm Not Jed Clampett
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2,725 Posts
eau contraire...:D
They do need a warning light. You need a bulb with two connectors.Ign switched 12v to one side of the bulb,and the other side to the terminal on the alternator..:tup:
Can you explain how that works then? The one wire is connected to the alternator B terminal at one end, and to the unswitched positive at the battery end, so how would the bulb ever light with 12v on both sides of the filament whenever the ignition is turned on?
 

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I'm Not Jed Clampett
Joined
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2,725 Posts
Hi,

So does that mean I have to run the charging wire from the alt thru the ammeter then to starter?

Also, I do have three relays to feed under the bonnet so trying to find an insulated terminal like this to avoid too many wires lashed onto starter.



Had a swatch at Premier and CBS but struck out :cry: Any ideas?

Cheers!
KJ
first of many sparky questions to come! :wave:
If you want to connect to your ammeter (check the full scale amperage first-it may be a lot less than your alternator will poke out when the battery is a bit flat, you may end up with the needle jammed off the scale) just connect from the alternator B terminal to the load side of the ammeter, the battery will be connected to the other side of the ammeter anyway.

What about using one of these boxes for your power connections:
http://www.vehicle-wiring-products.eu/VWP-onlinestore/battconns/battconn.php#jbox

Alternatively, you could make something up using some 2BA or M5 brass screws and nuts mounted on a lump of Tufnol or similar engineering plastic, this is what I have hidden under the dashboard of my old truck.
 

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drag race addict
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1,392 Posts
Can you explain how that works then? The one wire is connected to the alternator B terminal at one end, and to the unswitched positive at the battery end, so how would the bulb ever light with 12v on both sides of the filament whenever the ignition is turned on?
because terminal B is a ground until the alternator starts creating current so i'm led to believe.
I'm not a time served electrician but the guy who told me how to do it is,and the cadillac(and my own car)that i fitted a one wire alternator to works the way i described.
Surprisingly the light is on when just the ignition is switched,then when the car starts the light goes out AND it charges too!
 

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I'm Not Jed Clampett
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2,725 Posts
because terminal B is a ground until the alternator starts creating current so i'm led to believe.
I'm not a time served electrician but the guy who told me how to do it is,and the cadillac(and my own car)that i fitted a one wire alternator to works the way i described.
Surprisingly the light is on when just the ignition is switched,then when the car starts the light goes out AND it charges too!
Don't know about the alternator on your car, but a standard 1 wire alternator is connected to the +12V side of the battery i.e. a permanent live, if it had a ground connection on the B terminal it would flatten the battery PDQ.
 

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drag race addict
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1,392 Posts
Don't know about the alternator on your car, but a standard 1 wire alternator is connected to the +12V side of the battery i.e. a permanent live, if it had a ground connection on the B terminal it would flatten the battery PDQ.
But....if it had 2 wires like both of the ones i described had..:pmsl:
Forget everything i said.It's the pills i tell ya.:incheek:
 

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drag race addict
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1,392 Posts
That's not a 1 wire,which is the mistake i made..lol
A one wire has just the big thick wire and nothing else.I was thinking one wire as in one wire other than the thick one.:D
 

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I'm Not Jed Clampett
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2,725 Posts
I've wired mine up and it works. You have a 12v switched supply to lamp, but don't ground lamp wire it to small spade terminal on alternator, And other small terimal goes to a 12v supply to monitor voltage for built in reg in alternator!

Heres a link to a pretty picture...http://mightymo.org/public_html/images/Projects/DelcoOneWire/DelcoSI.jpg

Cheers Rich
Yep, that's a diagram for a Delco 10SI which is a three wire alternator, I've rebuilt several of those, I have one on my truck. Excellent piece of kit, but not a one wire alternator. One wire alternators conjure the field voltage up using a special type of internal regulator, so only need the Batt. connection.

My experience of one wire alternators has been that they don't tend to charge until the motor is revved up a bit, so I wouldn't rush to fit one to one of my rides.
 

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Stroker
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5,458 Posts
Discussion Starter · #12 ·
Thanks for the replies!

Been a canny learning curve on this stuff.

Googled it as well and there's loads of info out there. One site said 1 wire alts still have the other terminals.

I had a look at the 80amp Summit alt I got and blow me there's a rubber block which has the two other terminals hidden under it!?
I will hook up the ign sense lite and see if that still functions.

Think I've got all the info I need for a stab at it.

http://mightymo.org/Proj_OneWire.html
http://www.alternatorparts.com/FAQ.htm

Stueee, you got some great tech tips on your website too! :tup:

cheers
KJ
 
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