830 24v Electric start

Plant Doc

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A bare wire caused voltage regulator to burn up. Ordered new after market regulator and had generator professionally rebuilt. Replaced bad wire and installed new Generator and Regulator. Now it will not charge. I remove the regulator cover and pushed the Bat points together and it did charge, but the points would not release and burned up. I cannot get an original Delco regulator as they are no longer available and the new after market regulator supposedly is a direct replacement. I just bought and installed another new after market regulator from a different supplier and it still does not charge. I cannot afford to burn up another $100 regulator. It seems the generator will charge if the bat points are manually pushed, but it will not charge on its own. Even if I push the field points manually it does not charge. This is not my tractor but I was the one that rewired it 15+ years ago and it has worked great until this bare wire caused some damage. I traced all the wired to make sure they were all good and making good connections. I feel it is this after market regulator causing the problem, but do not know how to confirm it. All help will be appreciated.
 
Have you polarized the generator? Momentarily jumper between BAT and ARM terminals on the regulator to do this. Now with the tractor running at fast idle hook a voltmeter between the A1 terminal of the generator and the A2 terminal of the generator. You must have at least 25-26 volts to close the cut out relay portion of the regulator. If you don't hook a jumper wire between the F terminal of the generator and the A2 terminal of the generator and try again. If you still don't have the required voltage the generator itself needs tested. Let us know what you find.
 
When he manually closed the cutout points he polarized the generator.

Problem is you should NEVER, EVER, EVER push those contacts closed manually. That's the quickest way known to man to "let the smoke out" of the regulator and/or generator.

If the generator is charging, they WILL close. If it is NOT, pushing them closed is just plain DUMB, and fixes NOTHING.
 
(quoted from post at 15:57:08 08/30/17) A bare wire caused voltage regulator to burn up. Ordered new after market regulator and had generator professionally rebuilt. Replaced bad wire and installed new Generator and Regulator. Now it will not charge. I remove the regulator cover and pushed the Bat points together and it did charge, but the points would not release and burned up. I cannot get an original Delco regulator as they are no longer available and the new after market regulator supposedly is a direct replacement. I just bought and installed another new after market regulator from a different supplier and it still does not charge. I cannot afford to burn up another $100 regulator. It seems the generator will charge if the bat points are manually pushed, but it will not charge on its own. Even if I push the field points manually it does not charge. This is not my tractor but I was the one that rewired it 15+ years ago and it has worked great until this bare wire caused some damage. I traced all the wired to make sure they were all good and making good connections. I feel it is this after market regulator causing the problem, but do not know how to confirm it. All help will be appreciated.


1. STOP manually closing the cutout contacts!

2. "Full field" the generator (for a quick testing period) by jumpering "A2", and "F" at the generator. If the generator then charges at full capacity, it would point to a bad regulator, if not, a bad GENERATOR.

3. If you'd like, email me at [email protected] and I'll send you some helpful info.
 
Did the rebuild shop test run the gen. and reg. on a test bench before you picked it up ? If it worked properly there something is likely not wired up correctly.
Those 24V systems are not "normal" and are too easy to fry stuff when you go poking around like on a 12 volt.
 
As typical Bob and I agree, let me add a bit of theory FYI...

The way its SUPPOSED to work is ONLY after the gennys output EXCEEDS battery voltage, the cutout relay (between gennys output and battery) closes so the genny can get connected to the battery to charge it. HOWEVER if its not producing and you force and hold the relay closed you are connecting the battery to a low resistance current path via the genny thru the contacts which can over current and overheat and damage them SO I AGREE ITS A BAD IDEA TO FORCE AND HOLD (or they stick) THE RELAY CLOSED !!!!!!!!!! Its ONLY supposed to close AFTER voltage of genny rises sufficiently NOT before..........

You are supposed to Polarize BEFORE starting using the external MOMENTARY jumper wire method because if you start and the genny is opposite polarity from battery you could damage the VR or possibly genny !!!!!!!!!!! A closure of the cutout relay would "polarize" but current passes thru the relay contacts versus my preferred external "momentary" jumper wire method again BEFORE starting........

NOTE even if rebuilt at a shop and ESPECIALLY since the 24 volt genny is a two wire ISOLATED from case frame device the polarity may be different then when you take it home and connect it to your tractor !!! That's why one should correctly Polarize BEFORE starting.. I hope you didn't start at the wrong polarity and possibly damage the VR or genny YIKES

If you FULL FIELD the genny that creates max charge condition and essentially by passes the VR's control function so if its properly polarized BEFORE starting (to avoid risk of damage) and you then start and full field the genny if it still don't charge (and all else and wiring is okay) the genny and NOT the VR must be the problem. HOWEVER if it charges when manually full fielded but NOT otherwise, the VR and not the genny is the problem.

I have the Official John Deere 24 Volt System info as a PDF file, its one great source of help and technical information, sounds like Bob has you covered on that.

John T Too long retired Electrical Engineer and rusty so no warranty lol
 
Thank you John T. Before your reply I did as Bob suggested and put a jumper between A2 to F. It did not charge and just as I was going to test voltage between A1 and A2 I got a call from my wife. So I think you can guess where my time was devoted to next. As soon as I run a voltage test on the Generator I will keep you posted. Thanks for your info.
 

Pushing those cutout points together when the belt is removed . Is the best way to polarize and function check the generator. Opening the field points when motoring should increase the RPM's .
 

Hmmm...I just a few months ago bought a 830 24v regulator at the local Deere dealer...was shocked they had one in stock!
 
You're welcome thanks for the feedback BUT ITS BOB YOU MOST OWE THE THANKS INSTEAD OF ME, I just happened to agree with him as is typical....

On the 12 volt genny its output is across the Armature and the Grounded Brush, while on the two wire isolated from case frame ground 24 volt genny, it's still across the armature which is the A1 & A2 terminals and should well exceed the battery 25.2 full charge volts under open unloaded conditions IF ITS ANY GOOD. Then with FULL FIELD (by passing VR function) it should produce max charge....

I just hope it wasn't started with the genny at opposite polarity !!!!!!!!! POLARIZE FIRST If Bob doesn't e mail you the Official John Deere 24 volt system info and what else he has, I can try, BEWARE of some mis-information out there. FWIW I attended Buick and Deere's 24 Volt Seminar and it was great and whatever Bob posts I always like also.........

John T
 

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