Voltage regulator question

Mathias NY · Jul 9, 2012

I am about to reinstall a 6v regulator onto my generator. It isn"t a new regulator, it is the same one that was removed a week ago. It worked at that time and the tractor has not been run since.

Do I need to repolarize the regulator? I"ve never really understood this process, don"t know if it"s even needed, and don"t know how this should be done.

Thanks for the help.

teddy52food · Jul 9, 2012

You don't polarize the regulator. But do the generator.

teddy52food · Jul 9, 2012

What are you working on? it makes a differance if it is an A or B curcuit.

55 50 Ron · Jul 9, 2012

If you put it back together with the same polarity (+ to + and - to - ) as it was and only being apart a week, it should not need polarization. However doing the polarization again does not hurt anything.

Polarizing is done by momentarily touching a jumper wire between Bat and Arm terminals on the regulator and it is as teddy52food said, this polarizes the generator not the regulator. Of course this is done after everything is "wired up".

Janicholson · Jul 9, 2012

With respect, Only on an "A" circuit style gen. Not correct for a B circuit. Jim

souNdguy · Jul 9, 2012

as teddy said. gennies get polarized.. not regs.

most mechanical regs work with either polarity.. though if a mechanical reg is stamped with a specific polarity.. it will last longer set that way due to the metal on the points.

Mathias NY · Jul 9, 2012

Thanks for the replies.

It's an Autolite generator with negative ground. Generator has 2 wires that screw into the bottom of the regulator (which are not accessible when the regulator is attached). The regulator has one wire that goes to the ammeter.

Does this make it an A or a B circuit? I assume the wire that heads to the ammeter is the 'Bat' terminal. Which one is the 'Arm'?

JMOR · Jul 9, 2012

(quoted from post at 14:28:38 07/09/12) With respect, Only on an "A" circuit style gen. Not correct for a B circuit. Jim

know that it isnt the "book" way to polarize a "B-ckt" gen, but.............I have never had anyone be able to explain why the "a-ckt" Batt to ARM will not polarize a "B-ckt" generator, too. current should feed into VRs ARM terminal, into the generator's ARM AND through the VRs field control contacts & into the generator's field coils. Why not??????????

Janicholson · Jul 10, 2012

In a "A" circuit system, the field is externally grounded by the VR or Charge control switch. It gets its power from attachment to the arm (hot) brush inside the gen, or from a third brush picking up electricity (a little remotely) from the commutator segments. Thus when the bat to gen (or arm) jumper is used the field gets current through their windings. This creates residual magnetism in the iron of the field poles.

In a "B" circuit system, the field is grounded inside the generator directly to the case. The field terminal is provided with voltage from the regulation system (not grounded at all). Thus polarizing a B circuit requires flashing the Bat to the F terminal. Momentarily energizing the Field coils to make residual magnetism of the correct magnetic polarity.

Polarizing improperly can and will ruin regulator control components, or not do anything. Jim

barnE · Jul 10, 2012

Rebuilt lots of gens on cars. Never polarized very many. Worked okay anyhow. Dave

55 50 Ron · Jul 10, 2012

Thanks, Jim.

I'm not ashamed to say I'm a retired engineer and I didn't know about the "A" and "B" circuits. Sure seems to me that generators and voltage regulators should be marked as to which ("A" or "B") they are.

mEl · Jul 10, 2012

(quoted from post at 15:05:19 07/10/12) Thanks, Jim.

I'm not ashamed to say I'm a retired engineer and I didn't know about the "A" and "B" circuits. Sure seems to me that generators and voltage regulators should be marked as to which ("A" or "B") they are.

Improperly polarizing a B circuit can burn the VR points and stick them together, there is a special procedure for polarizing a B and the field wire must be disconnected to do so

Voltage regulator question

Mathias NY

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teddy52food

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teddy52food

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55 50 Ron

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Janicholson

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souNdguy

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Mathias NY

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JMOR

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barnE

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