Everything works on Shore Power, Nothing on Generator

Generator runs fine. Starts up and runs easy. Only thing I noticed is it will make a lugging nose on and off. But not as bad as when the A/C's were working and first powered on.

Also everything works as it should when on the 30amp shore power. I have a 50amp system but the RV park we are at only has 30amp power. It's just when I plug the power cord back into the coach that the A'C's, TV's microwave etc won't work. Crazy thing is water pump, lights etc still work?

Also I have noticed that the guy that owned it before me installed a disconnect from the house batteries to the engine battery. That way when you toggle the switch you cannot start the vehicle, generator etc. Also is supposed to isolate the engine battery so that if the house batteries run down you can still start the Motorhome by switching off the disconnect. That also is not working. I can start generator or coach with the switch toggled I the protect position which to shouldn't be able to do.

I noticed that it started doing this when I installed new Trojan Deep 6 batteries. But we have been on a few trips since then with no issues. Just figured the switch was bad or something.

Yes all fuses inside the coach have been checked and all breakers flipped off and back on including the 2 on the RV Guardian Generator.

I'm stumped. Thanks for the help so far

Three possible answers .. Note this assumes the generator actually runs.

Some background: If the generator fails then in the case of most modern ONAN generators the generator will shut off soon as you release the START button and give you a low-battery, not cranking fast enough, code. You know it was cranking fast enough cause you heard it start.. ONAN monitors the output and shuts down if it is not within lmites.


now: The suspect list:

#1 and 2 are circuit breakers on the Generator itself.. On mine unless the sun is at just the right angle it is hard to read the OFF and ON labels (There is no "tripped" position) so I stuck a peal and stick on to indicate, in my casem, the OFF position (since that side had room for it) Brother P-Touch, always at your side.

Suspect #3 is the transfer switch.. IF YOU HAVE ONE,, sometimes they fail to transfer.. This is epically true if you start the generator while connected to shore power (or shut down while connected to shore power) and have Air Conditioners running. this can cause one heck of what is called an "inductive spike" which arcs across the contacts and welds them in position.

Suspect 4 is also the transfer system.. On some RV's it is manual, You need to plug the shore cord into a matching outlet on the RV.

Check the auto transfer switch if you have one. Also make sure the power cord is plugged into the outlet if you do not have a auto transfer switch. Check breaker at generator. Ours will trip but it looks like it is Ok. You must flip it off manually then flip it back on.

Good advice.

1. Turn OFF and back ON, both on-generator breakers.
2. If #1 not the problem, the ATS is the next suspect. IF,repeat IF you are safe working around electricity, open the ATS and check for power IN and OUT.
3. If no power IN from generator, check connections between generator and coach wiring.

If you have an energy management system, it MAY be preventing your generator power from reaching the coach if it is too low. It can be too low(zero) if the generator circuit breakers have tripped or if the generator is out of adjustment for the proper voltage and frequency.
Your transfer switch is working otherwise you would not have any power to the coach from shore power. ALL input power goes through the transfer switch, whether it is on generator or shore power.

2chiefsRus wrote:
have you checked the breakers outside on the front of the generator?

Also X2.....

have you checked the breakers outside on the front of the generator?

X2 on the Automatic Transfer Switch.

it could be your auto transfer switch is not switching you between shore power and the genset. have you checked that to see if there's voltage coming out (don't get zapped!)