How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Hank F. Your Own Question
Hank F.
Hank F., Technician
Category: Small Engine
Satisfied Customers: 14682
Experience:  Certified on Onan and Generac generators
Type Your Small Engine Question Here...
Hank F. is online now
A new question is answered every 9 seconds

I have purchased a 3.3kva onan lpg generator which had only

Customer Question

i have purchased a 3.3kva onan lpg generator which had only ran an hour before an electrician put a screw through a wire and stopped it working. The company which made motorhomes here in aus just took it out and fitted a new one and this one sat in the corner for a few years until they where moving and put it up for sale. I purchased it and downloaded wiring diagram etc. I checked all measurements and eventually found the transformer had open circuit and when i removed it found the under side all melted. i purchased a new one fitted it, plugged in the stator wiring(which i think maybe the problem) and the unit started and ran perfect (the unit looks brand new oil, air cleaner etc as new). I fitted the geny and asked my electrician which one of the 5output wiring set ups to use as the output wires(4 of them) had been cut off when removing from the motorhome and i wanted to fit a 240volt power point to run a house with no power through a invertor/charger 12v. It started and worked for a while but i notice the lights inside were flickering. I then tried to start our air con which is smal and this unit should run and all hell seem to break loose, the invertor started making all sorts of noises, the geny surged and carried on so i turn it off. I tried to use the vacuum and same sort of response. So i removed plastic cover and gave the slip rings a good clean and re started . iT IS THE SAme, it will run a fan and now when i plug the invertor in the geny dies and code 12 comes up which is overvoltage. I am starting to think i may have wired up the stator wires which were unplugged(obviuosly the elec was trying to find what he had done) or i have wired the power point up wrong, it is wired with only one of the output wires from the circuit breaker as the pos a nuetral wire that is also earthed to the body and an earth wire which is also earthed to the body of the generator, so neautral wire and earth wire are basicaklly joined. i found this difficult to understand but the elec assured me that is ok, however he did not see the geny only the onan wiring diagram. I have a feeling i either have the plugs wrong on the top of the stator connector block or the wiring at the power point i fitted, any ideas?
Submitted: 1 year ago.
Category: Small Engine
Expert:  Hank F. replied 1 year ago.
Hello, my name is ***** ***** I am going to assist you with this. What is the full model number of the genset?
Customer: replied 1 year ago.
Customer: replied 1 year ago.
That's wiring diagram. Dis you get my message or can you not help
Expert:  Hank F. replied 1 year ago.
Sorry, I work 2 jobs, and help on Just Answer in the evenings. I was unable to log on last night, as I was having some upgrades done to my computer. On all of the KY units I have worked on, it was impossible to get the 2 stator plugs mixed up. The wires are not long enough on the one plug to be able to reach the wrong socket.But you can double check yours.All the wires on one plug are labeled P5-XXX, and all the wires on the other plug are labeled P6-XXX.The plug with the P5 wires goes toward the back of the unit, away from the carburetor. Without being able to see how you have the unit wires, I would suspect you have something wired incorrectly.You need to fully check the wiring connections against the wiring diagram - especially the reconnectable area. If that all checks out good, you may actually have a voltage regulation problem.
Customer: replied 1 year ago.
Hi at the stator there are two large plugs and the wiring that comes out of those plugs then plugs into the loom wiring with individual plugs which included a splitter wire the wiring diagram I could find shows 5 or 6 ways to plug those wires in depending wether it's 110v 240v 3 wire 2 wire etc etc this is the question I have on the wiring diagram which is the correct wiring for this unit thanks
Customer: replied 1 year ago.
Sorry just to add I was also asking about the 4 wires I had coming out of the unit for mains power they have been cut and just left through the hole outside the unit the problem is there are 4 not 3 and a 240v plug has three so we are unsure which ones to use and it seems to directly corilate to the wiring diagram if the stator leads I was talking about To assist the 4 leads are red and brown which cine from the circuit breaker we are only using the red as one power wire also a green which is to the body and are using as earth and a thicker black wire which comes down from the stator wiring and has a eye terminal and says negative or neutral in it and that branches out of the eye terminal and comes out as a blue wire which we used as the nuetral however as I said I am not sure if the wiring they is plugged in bear the main stator plugs is correct and the wiring diagram shows about 6 deferent ways to wire it up. I think you would need to look at the wiring diagram for this unit to assist me in any way with my original question. Thanks
Expert:  Hank F. replied 1 year ago.
I am looking at the wiring diagrams. I am actually an Onan technician.The problem is that we don't use 50 Hz units here in the states, so I have never had to rewire a unit. Do you only have the wiring diagram you mentioned, or do you also have diagram(###) ###-#### ***** you wire the load lines depends on whether you want 3 wire 120/240, or 2 wire 240.
Customer: replied 1 year ago.
Hi I would expect I would need three wire 240volts the diagram I have is called reconnection wiring and shows 5-6 different ways to wire the stator wires and that has a direct result on which if the wires you use at the power outlet socket. The one we thought it was has the two stator windings in series one side of the two stator woes left one foes to the circuit breaker and into the power outlet plug the other end if the two joined stator windings goes down to earth then bridges from that eye terminal to the nuetral of the power plug and then just the earth wire to earth. That leaves the brown wire from the circuit breaker nit connected and I have a feeling this us not correct and maybe we use one side if each stator for pos and nuetral but then do we get the nuetral from the other two stator wires joined through the splitter plug we thought hat would only give us 110v. If you could tell me which connection diagram we need to use that will probably answer all my questions. I don't have the reconnection page in front of me but there is about 6 different ways to hook up the stator wiring. If you could just tell me which picture from left to right say number 3 or picture 4 that would be what I need pkease. Cheers
Customer: replied 1 year ago.
What confuses me to is what does two or three wire mean all our power outlets have three wires pos. nuetral and earth
Expert:  Hank F. replied 1 year ago.
When you change those wires, you are not rewiring the stator. You are reconfiguring the output - there is a huge difference. If you are wanting a 3-wire, 120/240, you need to use the second drawing from the left.On it, note that the neutral is isolated, not bonded with ground. I am not sure how your 240 works over there.But here, for 240, you need to have 2 hot wires - not one. ON a 3-prong plug, you would have 2 hots, 1 neutral, and no ground. If you have a single hot wire carrying the full 240, and the other wires are neutral and ground, Then you need to connect the genset as 2 - wire, 240 only. That would be The last drawing on the right.
Expert:  Hank F. replied 1 year ago.
Ground, or what you call earth, is not counted in wire count. A 3 wire system will have 2 hot legs, and a neutral. Each hot leg would carry 120 volts. On a 2 wire system, you will have 1 hot carrying 220 or 240, and a neutral. You just explained to me that you use a 2 wire system - not a 3 wire system.
Customer: replied 1 year ago.
Ok so just to clarify if I want 240 v out of our standard 3 prong power outlets I would want to use a two wire system and which picture is that again just to be sure and ill have a look when I get home. As I said there us two wires coming down from the stator to the circuit breaker and then each one if those two wires hooks up to a red and a brown which come outside the generator waiting to be hooked up it sounds like I should be using both if those wires one as a pos and one as a nuetral and then just the green earth wire to the body and the body to a ground wire. I was told by my electrician that our neatest wires must be bonded to earth so would that mean I just keep that eye term to the body and use that wire from the stator as the earth on our three pin plug anyway I'm still a little confused i think but if you can just clarify which picture number I will look when I get home thank you
Expert:  Hank F. replied 1 year ago.
If electrical code where you are at requires a bonded neutral, then you need to use the 5th picture from the left.You will only use 1 circuit breaker.T1 and T4 will go to the splitter, T2 will be the ground, and T3 will be the hot leg to the breaker.
Customer: replied 1 year ago.
Hi again ok it was wired to diagram 5 already. I changed it to diagram 7 and started it up and it is doing the exact same thing. I have a small fan plugged in to one outlet and that is working fine but when I plug the invertor/charger into the other outlet plug the voltage fluctuates and the charger does not start and then the geny turns off with fault 12 over voltage now when I first got this going last week it was not doing this it would actually run the charger etc but I noticed the lights inside we're flickering. I then tried to start our small air con unit and I think that's when things started going a bit funny but it would still run the 70 amp charger and tv lights etc in the house. Then when we ran the microwave it started playing up and turn off. And then when we tried to run the vacuum the next day the lights inside would ho really bright them dull down and the vac would speed up etc no it is at the stage we have basically no power or very little. I did read up and it said it could be slip rings dirty so I have them a clean with scotchbrite pad and it made it no better maybe worse nit sure if related though. Any suggestions were i go from here.
Customer: replied 1 year ago.
One thing I have noticed is the geny speed never seems to change even when it was working ok a few days ago Also I have just noticed through a little hole on the bell housing I can see some of the stator windings and they have some black windings mix km with some red the bigger holes in the back of the bell housing show clean red windings but through this little hole I can see some black colour wires mixed with red.
Customer: replied 1 year ago.
I'm having some real issues I have another Yamaha 2,4 kva and when I plug that in the Yamaha geny revs up and the charger fires up on the invertor then I start the onan geny and plug in a fan it works fine then I plug the house wire in that runs to the invertor/charger and the light on the invertor goes green saying it us getting power the tv light etc work inside but the charger does not start So I unplugged everything from the onan and took the vacuum outside and plugged it in. As soon as I switched it on the geny turned off and code 12 came up. I have checked all ohm reading on stator and they all seem to be in the range specified except b1 b2 which is giving lower readings but looking at the diagram that is for the vr2 chsrger and when started it is charging perfectly It seems any largish load and it dies. The only thing I have not checked us the slip ring ohms as I cannot find what number leads on the pcb to test
Do you have any clues as to what might be going on.
Expert:  Hank F. replied 1 year ago.
The slip rings will not cause this problem.Without being able to get my hands on this unit, and give it a proper load test, the only thing I could think of would be that the voltage regulation part of the controller is bad.
Customer: replied 1 year ago.
Thank you for your help.
Expert:  Hank F. replied 1 year ago.