Plugging into shore power.... Buzzing noise

Just a quick suggestion..If you are going to change out that transfer switch, before disconnecting ANY wiring, grab your camera phone and take a few nice clear pics of how everything is wired up in the current unit. Also, if needed, mark the wires in whichever way necessary for you to remember what goes to where. (Wouldn't hurt to take pics with the wires marked before dis-assembly.)

Same thing happened to us while we were traveling out west last summer. Turned out to be the transfer switch. Call the mfg. and was told by the tech that a little buzzing can happen if dust or dirt gets in the transfer switch housing. We had ours replaced when we got home because the noise made my wife nervous. If it gets really loud it might be ready to go. You might not hear it with the generator on because the generator is louder.

Slojoe72 wrote:
^^^^. Is that wired the same? Would like an easy install, one that is wired the same.

The actual wiring is pretty straightforward, the length of the wires may be an issue. Because of the size of the wires involved and the limitations on the inside of the ATS enclosure they tend not to leave a lot of extra wire to work with. Different ATS boxes have slightly different wire lug locations. So if you decide to change to a different mfg, study the box layout and/or see if there is any play in the existing wiring if you need it.

They come pretty well marked and include instructions. Biggest problem would be labeling your wiring as to where they come from and where they go. The color coding should be the same. Black+ power, Red = power, White = neutral, Green + ground.

^^^^. Is that wired the same? Would like an easy install, one that is wired the same.

The ESCO LPT50BRD is the one I used, also a 30 amp version is available. Again, it has shore power priority and DC relays, so no hum.

I would look at the one you have and get one as close as possible.
Transfer switch

Ok sorry so long getting back
It's a Todd engineering power switch
Model ps250
I think I read they are out of business, what you recommend to replace?

Do you have auto start on genset? Turn off breakers on genset if you do. There should be no 12 volts.
Test the wiring before touching with meter or 120 volt test lamp.

Slojoe72 wrote:
soooo if I turn off the 2 main power 1 for the house batts, and other for motorhome disconnects, there should be any power at those wires ...... correct.

Don't know why there would be any 12vdc battery power in that area, but just to be sure and safe and especially if you're not well versed in electrical theory and using a voltmeter, shut off and unplug everything and you most certainly want to be unplugged from shore power. You might even want to remove the -neg. ground cables from your batteries, as you never know what might be by-passing your battery switches.