2005gulf
I have a 2005 motorhome with a Generac Quietpact 40G  item # 0047000   Series QP-40G    Serial 3881816    phase  1    it has 108 hrs on it  i bought this motorhome about 2 months ago and could not get roof A/C or microwave to work when generator was running, it works fine on shore power , so i had a Auto tech who works on my vehicles check to see if the generator was putting out any voltage we checked glass fuse on front and the 30 amp breaker switch both are good  we removed the couch inside the motorhome and found 3 wires that come out out the generator and are connected inside a box with wire nuts to a 6 foot wire that runs to the transfer switch . he unhooked the wire nuts and tested for voltage coming from the generator , he said it was  0.55 and that there was no voltage , about a week later i had my brother perform the same checks on the glass fuse and 30amp breaker and the wires coming out of the generator , he got the same results  0.55, we removed the generator from the motorhome and checked the slip rings they were a little dirty , we then cleaned them with 400 cloth we looked/checked the brushes they move back and forth in holder and looked fine no chipping or odd looking wear , we reinstalled and started generator still no voltage , i was told how to hook up hand drill and spin backwards to recharge field inside generator.  did that . still not putting out any voltage , was told to hold down generator start switch for a short time after generator starts that did not fix anything , looking for advice , thanks
Quote
78buckshot
Not having much experience on RV generators I will offer an educated guess. The generator has some type of voltage regulation and a system to excite the field, either one or both of those systems is suspect. If you can get to the wires for the brushes test those with an ohm meter to see if the rotor has open or shorted windings, same with the stator. If no shorts to ground and windings showing some resistance you will need to search for the voltage regulator and maybe an excitation circuit breaker.
Quote
Peddler
Jump battery voltage to the #4 wire on the voltage regulator while monitoring the voltage at the main breaker on the generator side.  It should jump up to over 60 volts AC line to line.  If you can do this with the #4 wire still attached to the voltage regulator then the voltage may go on up to 240 volts more or less.  If it does you are not getting a field flash if it goes up then falls back off when you remove the battery voltage then we'll have to check the DPE circuit but it is most likely the voltage regulator.
Quote
78buckshot
Thanks for the help Peddler.
Quote