Generator wiring for ‘29 Graham

[GrahamPaige29]

Hi guys. Before vivid I sent my 1929 Graham’s generator away to be rebuilt. It was finished and the guy said it’s working fine but I’m confused about the hookup and I can’t contact the guy. My new voltage regulator has connections labelled B , F , and L.  I thought the L was supposed to be A.  There is a thick and thin wire coming from the generator.  I  need help with the wiring. Here’s a photo if the regulator and a clear wiring diagram for the car.   Thanks a lot. Geoff. 

[Oldtech]

 If there is no A connection then I suspect this is a 60's Chrysler regulator for an early ALTERNATOR.  The regulator was just in the field circuit and the L meant (idiot) light.   You need to find out what conversions he may have made to the generator.  it originally had a 3rd brush control. No regulator, just a cutout.  But I'm a bit puzzled. 

Edited May 13, 2022 by Oldtech (see edit history)

[GrahamPaige29]

Olstech. Hmm me too. I'll try to get a hold of the guy. He said he replaced the coils inside but the voltage regulator/ cutoff makes no sense to me either. 

[Bloo]

It doesn't look like the one for the Chrysler alternator. It is too big and the wrong shape in my opinion. Some regulators intended for tractors have a lighting terminal. Offhand I don't recall why. Is there a fourth connection on the other side of the regulator?

 

[GrahamPaige29]

Bloo. I took the unit off and there is a fourth connector under it. It's not labelleded but could this be "a"?

im going to guess that it is.  An I right thinking the large wire goes to "f", the small wire to "a", and the bat wire to the anmeter/battery????

[Bloo]

Almost. The most logical guess here is that it originally had just a cutout and someone installed a regulator. To do that requires a second wire be brought out. The biggest wire would go to the Armature, as that is where the charging current comes from. It must go to the mystery terminal if you have no A or ARM. F should go to the Field (small wire). B or BAT goes to the ammeter, you can depend on that one. L would be unused.

 

This is only a guess. Your mileage may vary.

 

 

 

Edited May 14, 2022 by Bloo (see edit history)

[TerryB]

Check this out, it agrees with Bloo’s idea it’s for a tractor.  The three brush generator would  have 3 terminals, one of which is L for lights.  A four terminal as your picture shows, is for a tractor generator that has a separate regulator.

https://www.steinertractor.com/IHS1258-6-Volt-Saddle-Mount-Generator-Cut-Out-Relay?gclid=EAIaIQobChMI55mJ5PDf9wIV1dOGCh2siQuREAQYAiABEgILcPD_BwE

Edited May 14, 2022 by TerryB (see edit history)

[GrahamPaige29]

Terri  I think that's it. I can't see what else the fourth terminal would be but the "a". I'm going to hook her up accordingly and see if I get current flowing TO my ammeter when running.   I'll just ignore "L". Thanks. 

[TerryB]

1 minute ago, GrahamPaige29 said:

Terri  I think that's it. I can't see what else the fourth terminal would be but the "a". I'm going to hook her up accordingly and see if I get current flowing TO my ammeter when running.   I'll just ignore "L". Thanks. 

Hold it!  I think your generator has the WRONG regulator, assuming the rebuilt unit is still functioning as a three brush.  Read the description, I think you technically have a four terminal regulator.  It is VERY confusing at this point.

[TerryB]

Note from the link I attached

• Note if your tractor is equipped with a voltage regulator, it will have 4 terminals total (3 on one side and one under the regulator or on the opposite side.)

[GrahamPaige29]

Terry. Excuse me while I go bang my head into a brick wall. I'm more confused than ever.   I think I have to find a mechanic locally who's used to antique cars. 

 

[GrahamPaige29]

This seems to have the right terminals. B. F. And A. But should it not also have a "cutout" to keep the battery from draining. Signed, confused. 

[GrahamPaige29]

https://www.steinertractor.com/ABC074-6-Volt-Voltage-Regulator

 

sorry link should be in above post. 

[Bloo]

This type of regulator is used with a third brush generator. The two relays inside are a cutout and a voltage regulator. There is no current regulator, so a third brush is still needed. The difference between this and a normal third brush and cutout setup is that there needs to be a field wire brought out. The other end of the field is still connected to the third brush. Some systems in the mid to late 30s had a setup like that from the factory.

 

If it is a generator originally intended for a setup like that, the third brush is probably non-adjustable. If it is a conversion of the original generator, the third brush can be set higher than it could have reasonably been set with just a cutout, but must be still low enough that the generator won't overheat. That means substantially less than the rated current listed in the manual, usually.

 

Edited May 14, 2022 by Bloo (see edit history)

[TerryB]

6 minutes ago, GrahamPaige29 said:

This seems to have the right terminals. B. F. And A. But should it not also have a "cutout" to keep the battery from draining. Signed, confused. 

Yes, I’m confused too.  Normally the third brush inside the generator acts as the regulator for output voltage. A cutout relay connects the generator to the battery.  The cutout engages when the generator output exceeds the battery voltage.  I’m not sure why you have two output wires on the generator if it’s third brush unless it’s not a third brush generator.  Bloo has replied, I want to see what he says.

[TerryB]

1 hour ago, Bloo said:

Almost. The most logical guess here is that it originally had just a cutout and someone installed a regulator. To do that requires a second wire be brought out. The biggest wire would go to the Armature, as that is where the charging current comes from. It must go to the mystery terminal if you have no A or ARM. F should go to the Field (small wire). B or BAT goes to the ammeter, you can depend on that one. L would be unused.

 

This is only a guess. Your mileage may vary.

 

 

 

Looks like this earlier post from Bloo is how your generator must work.  His connections to your regulator now make sense. ( I think but my head is starting to hurt😀).

Edited May 14, 2022 by TerryB (see edit history)

[GrahamPaige29]

If I recall correctly, the original box on my generator had the two relays inside it. As Bloo said, one out be the cutout and the other a voltage regulator. If I order this unit

https://www.steinertractor.com/ABC074-6-Volt-Voltage-Regulator

i am guessing this would work with my third brush generator. However I'm still unsure as to where the two wire emerging from the generator would be run. One is insulated, the other is thinner and uninsulated. 

[TerryB]

1 minute ago, GrahamPaige29 said:

If I recall correctly, the original box on my generator had the two relays inside it. As Bloo said, one out be the cutout and the other a voltage regulator. If I order this unit

https://www.steinertractor.com/ABC074-6-Volt-Voltage-Regulator

i am guessing this would work with my third brush generator. However I'm still unsure as to where the two wire emerging from the generator would be run. One is insulated, the other is thinner and uninsulated. 

Yes, that has me confused as well.  The large insulated wire is most likely the generator output wire or “A” terminal wire.  The uninsulated is strange.  If it was a field wire I would still expect it to be insulated.  

[TerryB]

Didn’t the generator rebuilder bother to hook up the wires? Seems odd…..

[Bloo]

99% the big one is the Armature (provides charging current), and the little one is the Field (used for control). I too would want to know for sure, in case someone modified it badly. Is there a band you can take off to inspect the brushes?

 

Here is what I would expect to see. The biggest wire should go to a main brush. The other main brush should be grounded. These 2 brushes are directly across from each other, and might be larger. The smaller wire should go to the field, which are the windings in the outer housing of the generator. The other end of those windings goes to the third brush. It's the one at an odd angle compared to the others, and it might be smaller.

 

Edited May 14, 2022 by Bloo (see edit history)

[GrahamPaige29]

Bloo I might have time tomorrow to owe her up and look. I'm guessing you're right about which one is which.  I think I'll order the regulator I referred to. It's only 30 bucks and seems correct. One other question. Should the body of the generator have a good solid ground to frame ( positive?). Thanks so much. 

[GrahamPaige29]

Sorry I meant open her up. 

[Bloo]

Yes, the case must be grounded. The only difference on a positive ground car is all the current flows in the opposite direction. Everything else is the same.

 

The charging current flows in a circle, from the Armature brush, through the cutout, then it branches 1) to power stuff in the car and 2) through the ammeter to charge the battery. Then, the two branches come back together where they ground. Then the current goes back all the way to the generator case, which is connected to the other armature brush, completing the circle.

 

Or, maybe it flows backwards, it doesn't matter. No part of the circle is more important than another, so bad connections anywhere will cause you grief.

 

[Bloo]

I wouldn't be in a big rush to order that regulator. I am not sure it will work, and am trying at this moment to figure it out, but I don't think there is enough information there. Also it looks like there might be camera distortion making it look narrow, and it might be a 3 relay regulator for a 2 brush generator. In any event, it doesn't look like it is meant to mount on a generator.

 

Is there something wrong with the regulator you have?

 

Edited May 14, 2022 by Bloo (see edit history)

[Oldtech]

Good thinking here people: at first I thought it was a tractor regulator, then I changed my mind. Can you show us the top if the regulator with the lid off. If it has a cutout we can likely confirm.  (only one set of contacts). It makes sense that the connection underneath is the armature but strange if it isn't marked some way.  And yes, it would help to know where the wires go inside the generator. 

[Bloo]

@GrahamPaige29, if you do have a look at the brushes, please take note about which main brush the third brush is closest to. I would expect it to be closest to the main brush that connects to the armature terminal. If by some chance it is closer to the main brush that grounds to the case, we will need to know it in order to make any decent guesses about how things should work.

 

I found the document that describes a third brush with regulator system with an L terminal for a tractor. While most of the it is spot on, the section we are interested in, the one that describes the "combined voltage current" regulator, seems deliberately obtuse and misleading.

 

http://www.navioneer.org/riprelay/The Navion Files/Delco_Remy_Generator_Regulators.pdf

 

And here is Delco document 1R-116 that @Peter R. posted in a Pontiac thread that describes normal 2-relay third brush setups without the "combined voltage current" feature and without an L terminal.

 

https://forums.aaca.org/topic/371632-generator-for-1936-deluxe-8/#comment-2302632

 

I'm not sure these documents help at all, as how to proceed will probably have more to do with what @GrahamPaige29 finds out when he has a closer look, but I thought you guys might want to see them.

 

[GrahamPaige29]

Hey guys.  I will take some serious photos today.  Thanks a lot.

[GrahamPaige29]

Hi guys. I dug up the original regulator.  I can see three terminals Bat  A. And  F. Thought that would be the case. I’m not sure why my rebuilder discarded this unit but maybe it’s safe to say it’s not working.   The generator does indeed have the three brush system and he installed new windings.   

[GrahamPaige29]

The new unit he put on the generator has four terminals. I’m guessing that it’s the wrong one as it has the additional “l” terminal.   I’m wondering if this unit would be suitable to install?  Link in post below. 

[GrahamPaige29]

Here’s the one I’m looking at…

https://brillman.com/product/6-volt-delco-voltage-regulator-generator-mounted-premium-quality/
 

PS. Does “Gen” on this unit equate to A?

[TerryB]

I would say yes, Gen=A or armature terminal.
 Last night I did more research on the “L” terminal on an antique farm tractor site.  Apparently the L terminal was used on some tractor voltage regulators and was connected to a terminal on the lighting control switch of the tractor.  When the tractor lights were turned on with the switch, some power was drawn from the L terminal. This in turn caused the generator field control circuit inside the voltage regulator to “bump up” the output of the generator to compensate for the power draw of the lights.  Not using this terminal on your car application should not interfere with the operation of the regulator.  Another interesting note on the tractor site was the use of “G” or generator instead of A for armature just like the regulator from Brillman.  I think you could use the regulator you have but I do think the one from Brillman looks more appropriate for your car.
 

I had a Dodge pickup that had a three brush generator and simple cutout relay mounted on it.  To regulate the output, the third brush was movable and you set the generator for best compromise output for both day and night driving by changing the position of that third brush.  A screw held the brush in place.  You would loosen the screw, move the brush until the desired output voltage was reached at the battery and then tighten the screw.  Not very complicated.  The downside of this setup was if the output was set too high it would overcharge the battery and run the cells dry.  Your regulator system that controls the field coil current based on load is much better.

[GrahamPaige29]

Hey Terry. Thanks a lot. I think I'll hook up the system assuming the bottom unlabelled terminal is armature. If L. being there has no effect on the system when not used I can stick with what I've got.   So field thin wite armature thick wire and bat to anmeter. 

[TerryB]

Don’t forget it may be necessary to flash the field of the generator to get it to work properly.  This action magnetizes the generator metal frame which in turn gets the output “ready to go” as the armature spins up to speed.  This card explaining the process may be of help.

 

 

[maok]

If originality is not a concern, just stick a one wire alternator in it.

[Bloo]

Who made the generator? is there a tag on it or anything? How about the original regulator? What are the numbers?

 

I think if it were mine I would try to get the old (original?) regulator going, but I would probably start by using the one the rebuilder put on it. New production mechanical regulators don't have a great track record, and I certainly wouldn't be buying any more of them for now. Maybe it's fine. Have you used it and was it not working? What was the original issue?

 

As for replacements, one that was linked way back early in the thread mentioned a "b circuit". "A circuit" and "b circuit" refer whether one end of the field is grounded, or if one end is connected to power. That is a common distinction in 2-brush systems, but I would expect a 3rd-brush-plus-regulator system like this with 2 relays inside the box to always be an "a circuit", so that one probably wasn't right.

 

Edited May 15, 2022 by Bloo (see edit history)

[Bloo]

5 hours ago, GrahamPaige29 said:

Here’s the one I’m looking at…

https://brillman.com/product/6-volt-delco-voltage-regulator-generator-mounted-premium-quality/
 

PS. Does “Gen” on this unit equate to A?

Yes, GEN and ARM or A are all the same thing. That terminal connects to one of the main brushes inside the generator. I also suspect this is the correct regulator for a system like yours. I am never 100% sure without complete information, but this one looks right.

 

Edited May 15, 2022 by Bloo (see edit history)

[studeboy]

Some tractor charging systems with a 3rd brush have the small wire go to a lighting/ charge control switch. it has a resistance coil in it. Pushed all the way in gives minimum charge rate. Pulled out to the first notch gives a high charging rate. Pulled all the way out turns on the headlights and the high charging rate. I have used and seen Massey Harris and John Deere tractors with this set up. 

[Oldtech]

11 hours ago, GrahamPaige29 said:

The new unit he put on the generator has four terminals. I’m guessing that it’s the wrong one as it has the additional “l” terminal.   I’m wondering if this unit would be suitable to install?  Link in post below. 

That is the wrong unit. My first guess was correct. There is no cutout. It is for an alternator. You need the tractor type.

[Bloo]

I disagree that it is for an alternator. That is the tractor version. The cutout is the relay on the left and the voltage regulator is on the right. You can also see the current winding on the regulator (the exposed heavy piece of magnet wire) that runs from the vehicle side of the cutout, which is also the "L" terminal, to the "BAT' terminal. This is all documented (badly) in that PDF I linked earlier in the last page or two. The text doesn't make much sense, but the illustrations match this. The L terminal powers the lights on a tractor.

 

I agree that is is the wrong unit, but I still think it might work. I am unclear on what behavior is supposed to be "new" in the tractor unit with the "L" terminal vs. the automotive versions (going back to the mid 30s) that have no current winding and no "L" terminal (and work fine). If it makes any difference at all, it probably is not an improvement when not being used on a tractor.

 

One thing I am unclear on from the PDF is whether they eliminated any other windings on the relays when they added the current winding in that "L" terminal version. If the windings are all there, you could just connect to the "L" terminal instead of the "BAT" terminal and you would be back to the automotive version.

 

http://www.navioneer.org/riprelay/The Navion Files/Delco_Remy_Generator_Regulators.pdf

 

I would still like to know what make and model of generator we are working on. Are there any tags? Any numbers?

 

Edited May 16, 2022 by Bloo (see edit history)

[Bloo]

2 hours ago, studeboy said:

Some tractor charging systems with a 3rd brush have the small wire go to a lighting/ charge control switch. it has a resistance coil in it. Pushed all the way in gives minimum charge rate. Pulled out to the first notch gives a high charging rate. Pulled all the way out turns on the headlights and the high charging rate. I have used and seen Massey Harris and John Deere tractors with this set up. 

 

There is no voltage regulator in that setup. Chevrolet used that in the mid 30s. In my opinion it is brilliant. On a 3rd brush alternator of the "normal" type with only a cutout, it will keep charging as hard as it can when the battery is full because there is no voltage regulation. Driving at night there was never enough current, and driving in the daytime with a fully charged battery there was too much. This system you describe sets a lower charge rate with the headlights off, and matches the car (or tractor)'s needs far better, while still allowing the driver to turn the charging system on high if he knows his battery is low. It was a huge improvement over what was typical at the time, and all it took was one extra switch contact and a resistor to accomplish.