Genset is producing no power

[TicToRyde]

While camping, after a very bad storm, I had the Onan Marquis 7000 running with the rear A/C set on 'auto' and went to bed. During the night I heard the A/C compressor kicking on and off as the temperature would change. Around 4 in the morning I got up to use the boys room and noticed no power to the coach and the genset was still running. All the breakers, fuses, gfi's and the ATS switch have been checked out. I have no power at the junction box or at the main breakers. Before I go an spend a lot of time dropping it out of it's compartment and/or buying an expensive voltage regulator, can anyone think of something that I may have missed? Oh, and I have shot the rings with some contact cleaner already even thought they looked fine. The old gal has 403 hours on her.

Thanks!

[Retired_JSO]

Got it..

[TicToRyde]

Here is the pic of the breakers. Hopefully this works as I have never tried to post a pic before.

[TicToRyde]

My generator has two main breakers. When you overload it they are the first thing to trip. They are located on the side of the generator. One is a 20 amp and one is a 30 amp. I realize that some gennys have just one what I call "main breaker" but this one has two. That's why I have been referring to them at 'breakers'. Everyone that I have asked about this, that's their first question they ask me is if I checked them. To my knowledge and based on the Onan manual that I have, there are no other breakers on the genset itself.

[Retired_JSO]

TicToRyde wrote:
The breakers were the first thing that I checked and they had not been tripped. I did reset them, reset the gfi and all of the other breakers in the coach. I also changed every fuse even though none appeared to be blown.

You keep saying the breakers. Did you go look on the generator (on the green box) itself where it's output breaker is located?

[TicToRyde]

When we removed the cover where the starter switch is, it looks very similar to the pics on this thread.

http://www.mytractorforum.com/showthread.php?t=99700

[TicToRyde]

There is a junction box above the genny and I checked those wires. Also, we put the voltmeter to the circuit breakers. We removed the cover which exposed a lot of wires that slip onto a group of of tabs which are mounted together on the side of wall against the generator. Any wire we could see we put the voltmeter on it. It was registering practically nothing.

[st687]

Where did you check the power on the genny.

[TicToRyde]

I have to remove one of the rear night stands to access the ATS and will give it a whirl but it seems as though there is no power from the genset to the ATS for it to engage.

[MrWizard]

the 'coil' is Inside the relay/contactor

on my 50amp rig, the transfer switch has TWO contactors in the box

one engages when on shore power

the other one engages (after time delay) when the Onan is running

[TicToRyde]

I am somewhat electronically challenged so could you tell me where the magnetic coil is? One reason I haven't concentrated on the ATS is because there is no measurable voltage at the generator itself. I presumed that no power was actually getting to the ATS but I could be wrong?

[st687]

TicToRyde wrote:
Would something like the ATS switch fail in middle of the night when everything seems to be working fine? That's what is puzzling. One minute it's working the next I have nothing.

Yes,if the magnetic coil goes out the contactor opens.

[TicToRyde]

Would something like the ATS switch fail in middle of the night when everything seems to be working fine? That's what is puzzling. One minute it's working the next I have nothing.

[TicToRyde]

Not yet. To get to the ATS switch requires some major work to obtain access. I believe it defaults to the generator but am not sure. I know when I plug in the shoreline I hear it click and then the power comes on.

[st687]

Have you checked the contactor's in the ATS to see if the one for the genny has dropped out.