Momentary Swiths on Dash for Polarizing the Generator

Is it OK to install a momentary switch on my dash for polarizing the generator? Am I missing anything here? I was just going to use a starter, push button type switch. I always disconnect the battery when we are not using the tractor.

Bruce
Rockdale, Texas

It should take months, years, for the generator to lose polarity.

But I guess you could if it's presenting a problem.

There is absolutely no need for a switch that when pushed can over heat the generator (by a person (not you))deciding it was the starter. Generators 20 years laying dormant have still held their magnetic charge in the pole shoes well enough to start generating. Jim

Do you have to polarize the generator every time? You shouldn't need to; it's not required just because the battery was disconnected. Do you only unhook the grounded cable from the battery?

When I disconnect my Battery after using the tractor, when I reconnect it will not charge until I polarize the generator. Is there something going on that may be causing this?

Thanks
Bruce
Rockdale, Texas

A bad regulator can have a cutout relay that is out of adjustment and won't pull in and connect the generator to the battery. Polarization is done when the tractor is not running. connecting the Bat terminalon the regulator to the Arm terminal. If the generator charges OK when it does charge, the regulator is at fault. If you need to polarize it when running it is for sure the Voltage regulator. You can get by as you are with the momentary contact switch as you intend, but a new VR is the fix. Jim

(quoted from post at 15:27:24 11/03/22) A bad regulator can have a cutout relay that is out of adjustment and won't pull in and connect the generator to the battery. Polarization is done when the tractor is not running. connecting the Bat terminalon the regulator to the Arm terminal. If the generator charges OK when it does charge, the regulator is at fault. If you need to polarize it when running it is for sure the Voltage regulator. You can get by as you are with the momentary contact switch as you intend, but a new VR is the fix. Jim

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Thanks for the tips Jim, When I get out to the farm Saturday I'll mess with it more.

Bruce
Rockdale, Texas

Especially as long as the generator remains assembled, if alls well, POLARIZATION CAN REMAIN OKAY AND
UNCHANGED for months upon months,,,,,,,,,,Re-Polarization is NOT required prior to each tractor re
start,,,,,,,,,,,,,,Polarization is NOT necessarily required if battery is removed or replaced.

HERES WHY Polarization simply passes current through the field coils which imparts a degree of residual
magnetism in the soft iron poles at a certain North South magnetic polarity resulting in the certain + or
- Electrical polarity so it charges at the correct polarity to match the battery. When you remove the
battery thats the same as the VR's Cutout Relay opening which it should?? when the tractor shuts down IE
just because you remove the battery you dont need to re polarize (its already removed by an open cutout
relay)

Failure to charge can happen even if the genny is fine DUE TO A FAULTY REGULATOR

To determine the cause of non charging and see if its more likely a genney orrrrrrr a VR problem, try my
Troubleshooting Procedure linked below. If you want to install a method to polarize fine BUT I DONT THINK
THATS YOUR PROBLEM

https://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ttalk&th=2060825

Hope this helps

John T
John Ts Charging Troubleshooting

Are you "polarizing" the generator with the engine running?

I used that trick when I had a bad VR on my Super A. "Polarize" it and it would charge for a while. A new VR solved the problem. Had to replace it twice because the new VR was bad out of the box.

One of my Cubs sat for over a year, and charged fine once I got it running.

(quoted from post at 07:09:24 11/04/22) Are you "polarizing" the generator with the engine running?

I used that trick when I had a bad VR on my Super A. "Polarize" it and it would charge for a while. A new VR solved the problem. Had to replace it twice because the new VR was bad out of the box.

One of my Cubs sat for over a year, and charged fine once I got it running.

Click to expand...

I've done it before and after starting. Usually reconnect the battery, polarize and then start up. The generator and regulator are new.

Bruce
Rockdale, Texas

I've a generator & mechanical regulator on my Case 188D engine, neither too terribly old. Also have a battery disconnect switch to prevent shorts while I'm servicing. Every single time I disconnect the battery, I must polarize before starting. I considered a switch like you proposed but decided it's just too risky for the charging system. Finally marked & learned which terminals to jump so just takes a sec. Just have to remember to do it before you climb all the way up to the seat!

This post was edited by WilBury on 11/04/2022 at 08:04 am.

(quoted from post at 10:54:56 11/04/22)

(quoted from post at 07:09:24 11/04/22) Are you "polarizing" the generator with the engine running?

I used that trick when I had a bad VR on my Super A. "Polarize" it and it would charge for a while. A new VR solved the problem. Had to replace it twice because the new VR was bad out of the box.

One of my Cubs sat for over a year, and charged fine once I got it running.

Click to expand...

I've done it before and after starting. Usually reconnect the battery, polarize and then start up. The generator and regulator are new.

Bruce
Rockdale, Texas

Click to expand...

f you start one with generator polarization being the opposite of what is needed, you will be trying to reverse charge the battery & likely burn the cut out contacts......battery has lot of muscle!

I think what you are doing is not polarizing but 'exciting" it. I have that on the Cockshutt 50 that I converted to 12 volts. Added on a 37 amp Delco alternator in the process but it will not charge on start up until it is "excited" by momentarily flicking on and off a toggle switch I installed on the dash for just that purpose. You can see it on the ammeter soon as I flick the switch the needle jumps from zero up to at least 15 amps for a minute or so and then settles down as the battery charges. Been doing that for close to 30 years with no harm done.

(quoted from post at 14:51:44 11/04/22)
I think what you are doing is not polarizing but 'exciting" it. I have that on the Cockshutt 50 that I converted to 12 volts. Added on a 37 amp Delco alternator in the process but it will not charge on start up until it is "excited" by momentarily flicking on and off a toggle switch I installed on the dash for just that purpose. You can see it on the ammeter soon as I flick the switch the needle jumps from zero up to at least 15 amps for a minute or so and then settles down as the battery charges. Been doing that for close to 30 years with no harm done.

Click to expand...

I don't see exciting an alternator is the same as polarizing a generator. An alternator needs excitation power supplied to it for it to start charging. A properly functioning generator and regulator set up will start charging from the residual magnetism in the generator, it does not need to be excited by outside power. Polarizing basically sets the direction of current flow from the generator to match the vehicle system, since it can charge either positive or negative systems. An alternator has diodes, so the flow is only the direction the diodes allow, not convertible by simple polarization.

To me having to continually polarize a generator after a battery has been unhooked indicates a problem(s) with the generator and/or regulator. I have pull started vehicles with generators, having a dead or no battery in them, by getting them turning over fast enough that the generator starts charging enough to power the ignition.