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Rotating Diodes Checking


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  #1  
Old 11-09-2017, 09:23:08 PM
EnginePat EnginePat is offline
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Smile Magniciter Diodes Checking

I was looking at a onan 12mdjc that the owner claims the rotating diodes are bad in it , he said a friend checked them and that's what's wrong with the machine. Could I please get schooled on the proper checking procedure.
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MODEL 12MDJC-3R/2268R
SPEC 0968061905
120/240 1 PHASE 50 AMP
06SX1N3B
12JC33N4C
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Last edited by EnginePat; 11-10-2017 at 12:34:36 AM. Reason: Wrong title
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  #2  
Old 11-09-2017, 09:45:02 PM
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Jim McIntyre Jim McIntyre is offline
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Default Re: Rotating diodes checking

This is a magniciter set, right? No rotating diodes in it.
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Old 11-09-2017, 10:07:13 PM
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BigBlockChev BigBlockChev is offline
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Default Re: Rotating diodes checking

If that is the set in your post then I'm with Jim, if it is a different one let us know. Rotating diodes are a bit of a pain to check. They are covered in the YD gen end manual, but a certain amount of disassembly is required. Cheers Dan
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Old 11-09-2017, 10:11:30 PM
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Default Re: Rotating diodes checking (magniciter )

The Owner of the set said the diodes that were under the cover of the bell end were bad. I asumed they were the rotating diodes. Are there diodes in a magniciter end?
This is the set they may be in.
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Last edited by EnginePat; 11-10-2017 at 12:35:51 AM. Reason: Wrong title
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Old 11-09-2017, 10:48:33 PM
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Default Re: Rotating diodes checking

Yes there are diodes under the endbell on a magneciter set, they are not rotating diodes , they can go and are not hard to replace , nor are they very expensive. There is a good thread in the stickys on magneciter theory and troubleshooting. It is long but enlightening. Cheers Dan

https://www.smokstak.com/forum/showthread.php?t=45741
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Old 11-09-2017, 10:50:12 PM
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Default diodes checking (magniciter )

Thanks Dan!
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Last edited by EnginePat; 11-10-2017 at 12:36:45 AM. Reason: Wrong title
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Old 11-09-2017, 10:57:03 PM
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Default Re: Rotating diodes checking

And make sure that you take a good look at those saturable reactors. Make sure they're a nice tan color and not burned. Seller could be trying to pass off bad reactors as bad diodes.
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Old 11-09-2017, 10:59:45 PM
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Default Re: diodes checking (magniciter )

Right tan color good! Black ng!
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Last edited by EnginePat; 11-10-2017 at 12:37:44 AM. Reason: Wrong title
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Old 11-10-2017, 01:12:34 AM
pegasuspinto pegasuspinto is offline
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Default Re: Rotating Diodes Checking

REALLY REALLY simple to toss the magnecitor regulator and pop in a Power-Tronics unit. Works quite well. Assuming the rest of the set is OK I wouldn't worry much about the magnecitor being bad.
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Old 11-10-2017, 02:27:22 AM
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Default Re: Rotating Diodes Checking

You could do that, but you would be replacing a few rugged possible points of failure with what, hundreds? thousands? Of delicate points of failure. Better to just buy a YD generator equipped set in the first place, and keep a few spare regulators on hand.
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