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Polarization

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ronzet

ronzet

Jedi Knight
Offline
ONE MORE TIME....

I have been told that to polarize my regulator and generator for POSITIVE ground requires a quick short between the F and the A pole on the regulator....

I grow weary purchasing regulators....

Thanks..
 
Instruction on how to polarize a Generator:


In all the years I have been in business, I have heard many versions on how to polarize a generator and voltage regulator. Some versions are correct, others are totally wrong.
Polarization is a procedure which matches the polarity for the generator and the voltage regulator. The majority of the vehicles are manufactured negative ground although some of the older vehicles were manufactured positive ground. The generator has to be set up for either polarity. The generator will charge either way, however the voltage regulator has only one polarity. Whenever the battery is disconnected from the vehicle for any reason the polarization procedure should be performed.
The recommendation on how to polarize a charging system is the following: After the installation of a battery, generator or voltage regulator follow these procedures. The terminals on the voltage regulator are labeled with letters and this is where you will do the polarizing procedure. Both of the components will have battery power so do not start the vehicle or turn on the ignition switch before polarizing them. You will need a small piece of wire fourteen or sixteen gauge with alligator clips on the ends. Find the "B" terminal on the regulator and attach one of the alligator clips, find the "D" terminal and touch the terminal with the other alligator clip. You can touch the terminals a few times and it will produce a soft light spark. Under no circumstances touch the "F" terminal or any other part of the regulator or you could damage the regulator.
For the Lucas voltage regulators that have the teminals labeled A1, A, F, D, E, the polarization procedure is the same however the terminals that will be used are the "D" terminal and either the "A" or "A1" depending on which teminal is used on the vehicle. Either terminal can be used if wires are going to both terminals.
Start the vehicle and you should see the red generator light go off on the instrument panel, you may have to rev the engine up a few RPM, generators have a tendency not to charge at idle speed. If you have a gauge on the instrument panel the gauge will respond accordingly.
Look for more technical information in the future on these page.

Sincerely,
Mike Martinez
 
"Whenever the battery is disconnected from the vehicle for any reason the polarization procedure should be performed.
The recommendation on how to polarize a charging system is the following: After the installation of a battery, generator or voltage regulator follow these procedures ..."

???
Is this correct?
I don't know how many times I have disconnected the battery on my positive-ground '64 MGB but it's a bunch, and I have never, not once, not ever, polarized anything when hooking it back up.
Am I misunderstanding something or have I been the beneficiary of the Luck of the Innocents?
 
Ron - Talk to Bob Jeffers at bobj20@comcast.net regarding your charging circuit, he is the expert on the subject. He should be able to help you determine why you are going through so many regulators and will make up a solid state regulator in the original regulator case if you want to go that way. It is necessary to polarize the generator whenever you install a new one so that it will put out the proper polarity. There is no reason to polarize a regulator as it is nothing more than two or three relays and they don't care what polarity is put on them. Polarizing the generator is as simple as disconnecting the two wires from the terminals, attaching a jumper wire to the smaller of the two terminals and touching the other end of the wire quickly to the battery connection at the starter solenoid. This magnitizes the field poles in the correct direction so they will cause the generator to put out the correct polarity when it starts rotating. Reconnect the tow original wires to the generator terminals and you are good to go.

You now have two conflicting stories on polarizing the regulator - pose the question to Bob Jeffers for the correct answer.
Cheers,
 
Ronzi, No. If the vehicle has sat for a loooooooooong time and the residual magnetism has "escaped" from the magnets in the field(kinda like the Lucas smoke) then you may need to polarize it again. But should not need to do this any and every time the battery is disconnected or goes dead.
 
"If the vehicle has sat for a loooooooooong time and the residual magnetism has "escaped"..." The car would have to sit for many years for this to happen. All the generator needs is just the slightest amount of residual magnatism to get started generating electricity. This is because initially the regulator is set to feed back all the voltage from the output to the field coils, which reinforces the residual magnatism in the pose pieces. it is not until the output voltage is somewhere around 14 volts that the regulator kicks in and limits any further feedback and thus any further voltage rise. Even something with as small a voltage as a flashlight battery is sufficient to produce enough magnatism in the field pole pieces to get the generator started.
Cheers,
 
Dave, that's why I extended the long to looooong. As often these cars sit through teardown, storage and then restoration. I think in my other tool box, I still have the Standard/Blue Streak regulator point adjusting tool. I know that I finally got rid of the fishscale that I used for checking regulator spring tension. Let's just say, I do have a little familiarity with the generator, regulator, magneto systems used a few years back.
 
Hello David,

"You now have two conflicting stories on polarizing the regulator".

The version you gave is correct, it is simply the polarity of the field, nothing to do with the regulator as you say.

The term used over here in the U.K. is quite descriptive, "Flashing the field".

Alec
 
We have laws against that flashing stuff here.
 
"The term used over here in the U.K. is quite descriptive, "Flashing the field".

"We have laws against that flashing stuff here."

Yeah, we try to avoid using that term too freely over here, it tends to make the vice squads nervous /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
Cheers,
 
I have used the method Dave D. Described on many cars and it works like a charm every time, changing polarity is a very simple procedure (a little more complicated if you have an electric tach) that can be accomplished in a few minutes and is the best way to go if you plan on putting in negative ground accessories, such as a modern stereo-in my humble opinion.

I am also skeptical about the every time you disconnect the battery statement, I disconnect the battery all the time on my car, never re-polarize--no ill effects, actually no effects whatsoever.
 
Thanks David....

Now the real question... I bought the generator from VB and it has an etched warning that the generator is wired for negative ground. Mine is still positive ground.

I realize the simplicity of polarizing the field coil in the generator... I must wonder, however, if this generator is HARD wired with the field and the D terminals in fact reversed.

If I have wired the D (yellow) to the field terminal and the field (yellow/green) to the D (owing to a difference in the internals of the generator) then no matter how often I polarize (flash) the field it will never polarize correctly.

Comments???

I will probably pull the generator out of my B, swap pullies, and use it for the time being until I can sort this mess out... I have NEVER had a problem with any of my generator based cars until I got this generator from VB.

I am feeling very, very, very frustrated... /bcforum/images/%%GRAEMLIN_URL%%/wall.gif /bcforum/images/%%GRAEMLIN_URL%%/wall.gif /bcforum/images/%%GRAEMLIN_URL%%/wall.gif /bcforum/images/%%GRAEMLIN_URL%%/wall.gif /bcforum/images/%%GRAEMLIN_URL%%/wall.gif /bcforum/images/%%GRAEMLIN_URL%%/wall.gif

So OK... Time for a beer... /bcforum/images/%%GRAEMLIN_URL%%/thirsty.gif
 
Ron - If the field and output terminals are crossed, you need a rfund or a correct generator from VB. I woubt that the field terminal can handle the current being drawn from the generator. You can check that the generator is polarized by removing the leads from the generator, jumper the two terminals together, then connect the red lead from an analog meter set to read 25 or 50 volts full scale to ground and the black lead to the jumpered terminals. Start he engine, but DO NOT REV IT UP! Slowly increase the engine speed while watching the meter. It should read up scale and increase as the engine speed increases. The generator should keep increasing with the engine speed, but do not allow it to go above 20 volts. As long as you get an upscale reading up to to 20 volts, the generator is good and putting out the correct polarity. If the voltage read up scale but will not reach 20 volts, the generator is polarized correctly, but not putting out sufficient voltage to work in the system. If the meter reads down sclae, the generator is not polarized correctly.
Cheers,
 
Put the dang generator on. Polarize it, and go for a ride. This is not rocket science folks.
 
Jack,

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Put the dang generator on. Polarize it, and go for a ride. This is not rocket science folks [/QUOTE]

I know that... BUT, when you do it right, check it again, and then it STILL doesn't work... argh.... /bcforum/images/%%GRAEMLIN_URL%%/wall.gif

Anyway, got a new regulator, my generator from my B, and a jumper wire, will install this evening... As for the VB generator, on the shelf and when I get around to it, I'll figure out what is amiss...

Thanks... Oops.. gotta go fix my Rocket.... It launches this weekend.. /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
Ron - If you are still having a problem when you get all through, I would seriously suggest taking the car over to a local auto electric shop (not Auto Zone, Kregers or that ilk, a real auto electric shop where they have greasy old generators, starters and alternators laying on the bench and have them look the system over). It might be a good idea to take along a diagram of the cars electrical system. If I had the car in front of me, I could get things straightened out, but doing it by remote control from 1500 miles away does more closely approach rocket science. The people at the auto electric shop should be able to sort thing out for you in a short time.
Cheers,
 
John Twist of University motors has posted a video on how to polarize the generator on You Tube. I think the title was "Polorize the MG" or something similiar. If you haven't been watching these you may want to check them out. He has done one or two new ones every week for a while and I have found them really helpful. Paul.
 
John really does us all a real service with these.
 
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