# Koehler 7000 7CKM22RV 120v



## Alan (Mar 1, 2013)

Is it possible to get 240 volts ac to run well pump, charge my electric van provide backup power to my home etc?.This 23 hp tagged 120v 6.3KV. 52.5 amp propane generator ser.#280486, spec140245,was built around 1994 for RV use it was removed from the RV, and I now have it running, mounted on a little trailer it has 2 30 amp 120v circuit breakers I measured 120volts on each circuit it runs 120 volt appliances very well. I observed 11 wires entering the service access box from the generator itself. 4 black AWG12 labeled #2 & #4 go to circuit breakers, 1&3 go to neutral post. 2 white AWG 16 labeled N,and P come in box and are connected to an electronic component mounted to the outside of the gen, 5 16AWG black labeled B1,B2,connect to fuse junction block in box,55, 99 and unlabeled go thru to same said electronic component.


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## KRE (Nov 29, 2011)

I do not have a print on that unit so don't know for sure. 
That said take your volt meter and check the potential voltage between the two hot 120Vac legs if it is 230-240 it can be changed to work just fine. If when you do this and the voltage is other than that, about the only way is to do a transformer, for 240. 
If you do a transformer do not over load the primary side, which is 1/2 of the Gen-Set's total rating.


Hope this helps,


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## Alan (Mar 1, 2013)

*Koehler 7000*

I put 1 probe on 1 120v wire #2 and the other on 120v wire #4 the 2 hot wires that go to the breaker switches and it read 2.3volts I did it more than once to confirm. so I cannot get 240 volts from this generator without a transformer, is that correct. what are transformer options?. Is there anyway to get a manual for this model? There is a small 4 terminal receptical on the side of the box it runs to the same circuit board plug as the starter switch any idea of what it is for would be appreciated? I think I will consider selling this as I would be happier with less hp and 240volt capability. thank you so much for your input. Alan


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## KRE (Nov 29, 2011)

2.3Vac means it's the same winding, so a transformer is your only out, with that unit. Many RV units are 120 only. 
I'd have to see a print to tell you about the plug, but most of the time it's either a start mode disconnect or part of the unit's safety system. 
You should be able to run the numbers on your search engine and come up with a print or tech Manuel.
Selling and getting what you need I believe, is your best bet. Many folks are looking for what you have just to run a deep freeze, freg, lights ect when normal power drops.
Good luck with your venture.


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## aandpdan (Oct 8, 2012)

I found a manual for you:

http://truckroadservice.com/barth_attachments/Kohler_Manual_7CKM21-RV_7CKM22-RV.pdf

You MIGHT be able to rewire the generator. It does appear to have 2 sets of windings in the stator hooked in parallel to get the 7kw. The good thing is, they have to be exactly the same in all aspects.

If you wanted to try something, at your own risk, disconnect the 4 leads from the generator. Using a jumper, connect leads 1 and 2 together. Start the generator and check voltages.

Between leads 3 and 4 you should have 240.
Between leads 1 and 3 you should have 120.
Between leads 1 and 4 you should have 120.

Just be aware that there is a jumper on the input side of the circuit breakers that you'd need to remove. The above SHOULD work but watch your loads. You have to balance it between both legs.

Hope it helps.


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## Alan (Mar 1, 2013)

when you say jumper I envision a wire connecting the #1 wire to the #2 wire is that correct? thank you for your help the manual already straightened me out on a few things my ice is rated at 13.8hp. I had determined from another source that it was 23 hp and that did seem out of step for that size gen.thanks again, Alan


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## aandpdan (Oct 8, 2012)

Yes, a jumper is used to connect the two leads together.

*Disconnect *all 4 leads first. Then connect leads 1 and 2 together. Don't try any other load at first - this is just to see if it is possible. If the voltages check out then you can put a load on it.

There are many Generac generators that are wired this way. They have a "voltage switch" so that you can either get 120v at full capacity or 240 at half capacity. 

You should have:
Lead 1+2 = neutral (N)
Lead 3 = Line 1 (L1)
Lead 4 = Line 2 (L2)

Dan


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## Alan (Mar 1, 2013)

*voltage test*

When I hooked up my awg 14 or 16 alligator clip 16" jumper wire across #1and #2 and started the gen up, it started very hard, ran rough, and melted the insulation off the jumper wire before I could check any voltage. I shut it down . are the alligator connectors inadequate and or is my jumper wire to small? any other thoughts. thank you Alan


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## Alan (Mar 1, 2013)

*oops*

I just realized on my gen, as I stated in my orig post #1 & #3 were hooked to neutral not #1 & #2 , my bad.


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## aandpdan (Oct 8, 2012)

If you didn't disconnect the other wires you just shorted out your generator. Hopefully it's OK and the 14 gauge wire burned up first.

I've attached a copy of the wiring diagram with the modifications I'm describing, if it passes the test.

The *RED* area I highlighted, you need to remove that jumper from the breakers. 

In a nutshell: swap the wires going to leads 2 and 3 on the generator.

Wire 2 gets relocated to lead 3 (circuit breaker feed).
Wire 3 gets relocated to lead 2 (ties in with lead 1).
Lead 4 stays the same.


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## Alan (Mar 1, 2013)

I cant seem to post


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## Alan (Mar 1, 2013)

I had disconnected all the wires including the jumper on the breakers . this generator had 1 & 3 going to neutral, 2& 4 went to the breakers as I described in my original post .If I swap then I will be connecting 1&2 to neutral & 3&4 to the breakers and connect them with that jumper the way 2&4 were before, is that correct? Your last reply tells me to wire it the same way it was originaly I am confused. thanks for your understanding


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## aandpdan (Oct 8, 2012)

No, I don't say to wire it as the original. Yes, 1&2 should go to neutral now. 

Look at the diagram I attached. Hook it up like that.

You've removed the jumper between the breakers. Good. You can not use it if running 240 volts.

Then, swap the wires going to terminals 2 and 3 on the generator. That's it. 

Keep the breakers off then start it. 

Can you measure the voltage before the breakers? The line side? It just avoids any problems with receptacle configuration, etc.


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## Alan (Mar 1, 2013)

*rewire*

I followed your test proceedure exactly in every detail, and the jumper wire insulation melted I assume it was a dead short. I will not attatch wires 1 & 2 together after seeing that. there are no number labels inside my control box,what I call neutral is labeled GRD & then there are the 2 breakers. I decided to measure the AC voltage from all 4 AWG 12 black wires coming from gen individualy unattatched with it running for what it is worth they were 1=66, 2 =49, 3 =92, 4=80. the other test wire was clamped to equipment ground terminal.


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## aandpdan (Oct 8, 2012)

Looking at your readings it appears there may be multiple windings in the alternator. Without a diagram we can't know for sure.

We tried.


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## KRE (Nov 29, 2011)

Alan said:


> I decided to measure the AC voltage from all 4 AWG 12 black wires coming from gen individualy unattatched with it running for what it is worth they were 1=66, 2 =49, 3 =92, 4=80. the other test wire was clamped to equipment ground terminal.


Those numbers tell me, you have two windings that are in-phase. They have to be out of phase to increase potential.


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## Alan (Mar 1, 2013)

thank you very much for all your help guys I learned alot I like that ,we had some smoke but no fire,the whole exchange was .challenging & fun. I have hooked back up the way it was & given my wife a lesson on how to use it. I maybe putting it up for sale or trade in the future so I can get that 240 volts.and thanks again.


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## Alan (Mar 1, 2013)

Is it .nessesary & what is the proper way to ground this machine if it is on a rubber tired trailer for general use. and what if I wanted to use it with an interlock system to feed my existing home in case of outage would that require different grounding.


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## KRE (Nov 29, 2011)

I would not hook a 120Vac only unit to a home for a number of reasons. If it were me and knowing what your goal is I'd, suggest just running cords to that unit should you need it before you acquire what/need.

As far as grounding once you acquire your wants/needs, inquire with your local electrical inspection office. The regs are all over the place depending where you live. NEC states one thing, local states differently, and what works the best for safety and lightening, is completely different yet.


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## aandpdan (Oct 8, 2012)

KRE said:


> Those numbers tell me, you have two windings that are in-phase. They have to be out of phase to increase potential.


The kicker is, if he's measuring from one lead to ground, unless the stators are tapped, he shouldn't read anything for voltage.

I'd love to know exactly how the generator is wound.


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## KRE (Nov 29, 2011)

aandpdan said:


> The kicker is, if he's measuring from one lead to ground, unless the stators are tapped, he shouldn't read anything for voltage.
> 
> I'd love to know exactly how the generator is wound.


Many, Stators (rope start engines and otherwise) are internally grounded. This type of winding has many advantages, but some disadvantages as well.


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