I have a 2000 motorhome with the original 8k quiet diesel…

What is the Year, Make and Model of the RV? ALL you need to do is check for voltage on the hot and neutral and see if you have power at the TS you will have incoming shore power, incoming generator power. IF you have AC voltage on the black and white (black should be hot white should be neutral) check the output side and see if you have voltage, if you ONLY have AC voltage on one side that it is bad. The relay can stick and once they do that they should be replaced. From what I can tell the TS 30 is a 30 amp transfer switch, click HERE and have a look. No worries on the phone service.... Robert

220 would be one HOT leg and sometimes owners plug into that and it is VERY damaging to the RV. IN a RV you have TWO 110 legs to equal 220 NOT 220 direct for a 50 amp service, your cord would have 4 prongs, a 30 amp service is ONE 110 volt hot leg cord would have 3 prongs. I am a little confused if you have a 50 or 30 amp service if you have that TS30......

OK

Honestly I am not sure on the inverter I am going to put your question back up for other experts, I do not know when another expert will respond, they come and go daily. No need to respond back to this as your question will be back up on the active list. My goal is for you to be satisfied and I am unsure if you have a 30 amp transfer switch with a 50 amp service.... Not something I have seen.... Robert

You don't want to have the genset running at the same time as the shore power is plugged in. Not good! You can damage the ATS. On measuring the AC voltage, you want to check between the red or black which are positive feeds and the white which is neutral. So based on that what is the voltage?

Not a problem. No dumb questions here. The ATS is the automatic transfer switch. Check the incoming AC power there and the power out. First with the one source and then the other. Let me know what you find and the AC voltage.

That genset puts out two 120 VAC feeds. One must be working for sure. Did you check the breakers on the set? Are you sure that someone hasn't mis-wired that ATS? Did it ever work properly?

And it sounds like someone added that 30 amp ATS and that the OEM ATS is still there. Did you look for one at the end of the shore cord?

The white wires are negative or neutral leads and carry no power. You test for AC power between the white and black. And you can't.......unless someone wired this up wrong.

The breaker on the genset may not be functioning properly. You could try checking the input on the genset side and see.......especially, if that is not the same on both legs. And you always want to test under load if you can. Switches and breakers that are failing do so more often under load.

Almost no load at all IF nothing is on. Best to have a manual on the genset to do that. Let me see if I can find one online for you. There should be two feeds and with a TS30 transfer switch you can only switch one leg. There has to be another one (ATS) there someplace.

If you don't then you could have AC power from two separate sources at the same time. That would be a bad situation. This had to have a 50 amp ATS from the factory. The lines from the generator and the shore cord end up there. What is the year, make and model of this RV?

See if this manual link is helpful........http://www.wanderlodgeownersgroup.com/downloads/ONAN%20MANUALS/Onan%20HDK%20Parts%20Manual.2pdf.pdf

It should have been an exploded view parts manual for the genset. If you can't find the OEM transfer swtich you might want to call in a good mobile tech for some assistance.