LocostUSA.com

Hey, folks - I just posted my ongoing conversion to one of these alternators (in my build log), which I picked up a couple of days ago for my Zetec-engined build. It's an OEM type, fitted to Geo Metro, Suzuki Swifts, and other GM tiny vehicles back in the '80's and '90's, and judging by the embossing on the sheet metal stamping over the back portion, made by NipponDenso (so, it's a Denso alternator).

Problem is, it has a round connector socket with three prongs in it (no problem making actual connections - standard, female spade connectors will work fine). Despite Googling my brains out, I can't find a diagram specifying which of the wires goes where. Of course, the large lug that's not in the round connector goes to the battery, but the three small ones...I figure one of them goes to +12V (ignition source) as the exciter, one goes to the dashboard ignition warning light, and the third goes to...where? And, which one is which??

Now, as these are tiny, cheap, plentiful, and powerful enough (55 amps) for Locost builds, I'm certain that some here have used them.

Can anyone enlighten me as to which posts in the connector (posts are numbered for convenience, in the photograph below) go where? I'd really appreciate the help!!

Thanks in advance!

Here's a pic of the connector socket -


and one of the alternator itself -

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/

I have an alternator bible here , the nippon alternators with that plug configuration are wired in two ways depending on model. I will need the number to give you the right info. On all of them terminal 3 is the ignition live, 2 is the ignition charging light and 1 can be a charge sensing terminal which goes to the battery or an earth wire. So really need to know the serial number/model of the unit.

Bob

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Build Log viewtopic.php?f=35&t=16640&p=187700#p187700

Mancave http://s1116.photobucket.com/user/mypic ... ow/mancave

I Googled "Denso Alternator wiring" and found this http://westfield-world.com/daihatsu_alternator.html

The picture of the car looks like yours so it must be right

Also give Bob the number...

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
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Thanks, guys! Clearly, I missed the pertinent links!

Bob- that still helps. Unfortunately ther are no casting or other numbers on the alternator, save for a damaged & incomplete UPC sticker. Nonetheless, I intend to bench-test the unit, using my lathe - if pole 2 shows continuity to ground, I'll know what it's for. If it doesn't, providing 12v to it should signal the unit to crank out current, right?

And Horizonjob's link has a couple of alternatives for wiring what appears to be the same unit, with that pole shown as +, but not -.

Thank you, gentlemen! I have a solid starting point and, when I can confirm what seems to work best, I'll report back.

- Mike

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/

I used one similar to that but I think it only had 2 connections in there. I didn't use the dash light one in my car. Sorry I'm no help.
Kristian

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V6 in a book frame build. Now registered.
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I did some more searching, and it looks like this is a Nippondenso 100211-6720 unit (I know it was for an '89 Suzuki Swift, and this appears to be the correct one for that year/model). I searched that model, and found this -


It looks like terminal #1 in my labelled photo is a "dummy" connection, which I assume means it's not used (or, it's intended to confuse morons like me...in which case, it's working!).

I tried spinning the alternator up on the lathe, with a 12V test light, but got nothing at all. Possibly, it needs to have the exciter wire connected before it will make any output at all.

Then, just for laughs, I tried my digital meter for continuity on the various poles to ground (the alternator's outer housing).

None had continuity...EXCEPT the main "BAT" post. My rudimentary knowledge of electrickery leads me to worry that this is a baaaad thing. Or...is it? Should there be continuity to ground (alternator not connected to anything except the multimeter), or does that mean it's internally shorted & a dud?

I also tried resistance to ground from the BAT pole, and got a reading of 6.8-7.0 ohms, settling at the 7.0 mark. I'm sure you electrical gurus out there can tell me if the above is bad or good?

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/

You will need to make sure terminal 1 is properly identified because if it is a charge sensing terminal and its not connected the battery will boil.

From the bible D is earth not dummy.

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Build Log viewtopic.php?f=35&t=16640&p=187700#p187700

Mancave http://s1116.photobucket.com/user/mypic ... ow/mancave

I think I'll take it to my local alternator testing place to be sure. I need to know if it works anyway, before I commit totally to using it, and hopefully they can confirm which poles do what. I don't want to take a chance & fry the diodes or something!

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/

Alternator testing shop confirmed the alt is fried (rectifier is cooked), so they're rebuilding it for me. Turns out that the terminal labelled #1 in my photo really IS a "dummy" terminal - on these alternators, that terminal isn't actually connected to anything inside. Apparently Nippondenso uses the same connector plug on other alternators that do use #1 for something. The black & white diagram I posted, above, is actually correct.

On the plus side, they were extremely impressed with the stepped adapter bushing I'd made to adapt the large 6-rib GM pulley to the smaller 15mm shaft of the ND alt. The counter guy actually called in the techs to see it - they liked it, a LOT. Have lathe, will travel, eh?

Hopefully, I'll have it back tomorrow.

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/

Its a shame about the fried alternator but at least it gets rebuilt and the terminals identified, there are plugs available for these if you need them with short tails http://www.ebay.com/itm/1-x-Connector-N ... fa&vxp=mtr

Bob

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Build Log viewtopic.php?f=35&t=16640&p=187700#p187700

Mancave http://s1116.photobucket.com/user/mypic ... ow/mancave

Thanks for the link! That will make life easier.

I'm keeping my fingers crossed that the windings etc. turn out to be okay. If so, I'll be happy - I'll have spent over $80 on a used alternator, but the place that's rebuilding it is as good as they come, so it should be as good as a thoroughly tested, hand-built alternator can be - a piece of equipment I'll never have to worry about again. Thankfully, it's also (as it turns out) dirt-simple to wire.

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/

I am using the same alternator on some of my projects, the same basic model comes in a few different lug/mounting styles and pully`s. Some are serpentine and others are v belt, the chunky mounts on the daihatsu version are the easiest to mount.

Bob

I got these from the local breakers and got the plugs at the same time

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Build Log viewtopic.php?f=35&t=16640&p=187700#p187700

Mancave http://s1116.photobucket.com/user/mypic ... ow/mancave

They sure are sweet units - powerful enough for a Locost (mine makes 55 amps), pretty much the most compact around, easy to make mounts for. I just got a call back from the alternator shop - its all fixed (problem had been shorted diodes - I'm guessing that's why it was just sitting on the seat of the car in the wrecking yard), fully tested, and ready to go.

Of course, I didn't get a connector with it, but as the socket has standard size spade connectors inside (and I have dozens of 'em), it will be a snap to wire up.

Seems like a sound $40 investment to me. Happy camper here!

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Scratch building, at continental-drift speed, a custom McSoreley-design framed, dual-Weber 45DCOE carburated, Zetec-engined, ridiculously fast money pit.

http://zetec7.webs.com/