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Onan 12.5JC Sorting it Out


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  #51  
Old 02-10-2018, 07:51:51 PM
consolenut consolenut is offline
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Default Re: Onan 12.5JC Sorting it Out

But the incorrect jumper alignment. Could it have caused the voltage issues I was describing earlier. I have since changed it V1 & V4 per the diagram.

However the weather isn't cooperating now to do anymore work on it today.
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  #52  
Old 02-11-2018, 10:51:18 AM
Wayne 440 Wayne 440 is offline
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Default Re: Onan 12.5JC Sorting it Out

Here you go- ref your PM.
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  #53  
Old 02-11-2018, 05:00:44 PM
armandh armandh is offline
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Default Re: Onan 12.5JC Sorting it Out

Quote:
Originally Posted by consolenut View Post
So which drawing are you referring to armandh
the ones on the first page posts 1,2

post 1 numerates the neutral cluster
post 2 diagrams low Y with every winding reversed from as connected

that will work

but yes I would do double delta or zig zag for US residential
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  #54  
Old 02-11-2018, 07:48:58 PM
consolenut consolenut is offline
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Default Re: Onan 12.5JC Sorting it Out

Thanks for your help guys. I do have one question. I have a 50 amp RV plug in my power panel. It has 2 hots a neutral and ground as described in the link below. It has and requires a neutral connection. If I send L-0 to ground in the generator control box. Where will my neutral connection be from the generator to the panel. As im assuming i need one. On my 6.5 my neutral and ground were tied together and connected to the neutral bar in my power panel. Any help appreciated

http://www.myrv.us/electric/Pg/50amp_Service.htm
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  #55  
Old 02-11-2018, 10:34:31 PM
consolenut consolenut is offline
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Default Re: Onan 12.5JC Sorting it Out

Thanks for your help. I'm gone. It seems everything Im reading the JC won't work in the configuration I want. So its off to the scrap yard this week. I'll stick to my 6.5NH.

Mods. Please feel free to close thread
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  #56  
Old 02-12-2018, 01:08:55 AM
Wayne 440 Wayne 440 is offline
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Default Re: Onan 12.5JC Sorting it Out

There are literally thousands of JC sets in operation in just the configuration you seek. I would like to see whatever it is that you are reading that states otherwise. Of course, if I was closer, I would try to get between you and the "scrap yard".
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  #57  
Old 02-20-2018, 04:01:59 PM
consolenut consolenut is offline
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Default Re: Onan 12.5JC Sorting it Out

well after a new board from.flight systems im back to square 1. ive still got high voltage. 145V and the machine i believe is running correct speed. its rock solid stable just way to high. the voltage pot is turned down. the damping pot is at 50%. ive checked the resistamve between t1 & t2 and its 14 ohms give or take. flight systems said that was okay
i measured resistance hitting start button and its quite stable. now at a loss on what to do! any ideas?
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  #58  
Old 02-20-2018, 04:27:16 PM
Wayne 440 Wayne 440 is offline
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Default Re: Onan 12.5JC Sorting it Out

I don't know what to tell you from hundreds of miles away, except that I would like to have that machine sitting in my shop. Sounds a very interesting issue to figure out that might keep me occupied for a while.
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  #59  
Old 02-20-2018, 06:35:30 PM
consolenut consolenut is offline
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Default Re: Onan 12.5JC Sorting it Out

well an incandescent light dont flicker. and the machine is at 1800rpm confirmed in a tach and dwell meter. frequency says its off but the voltage is steady at 130. everything points to the machine runnjng normally. power outage is 2 hours in.

my only thought is that frequency meter isnt reading right.
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  #60  
Old 02-20-2018, 07:09:50 PM
Max Thompson Max Thompson is offline
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Default Re: Onan 12.5JC Sorting it Out

What is the frequency meter reading? "IF" it is all wired correctly, running at 1800 rpm, and you have the jumpers on the new board in the correct position, all should be good. A $20 investment in a Kill-A-Watt meter may be a big help, I use mine often.

I just reread most of this thread and your responses do not instill a lot of confidence that everything is wired correctly.

I would not connect the set to your panel or anything other than a load bank until I was positive it is producing correct voltage and frequency from no load to full load.

Might be worth while to go back through "all" connections and double check things.

Please do not take any of this personally, NO offence intended. I have made more than my share of mistakes wiring these sets up.
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