Plugging into shore power.... Buzzing noise

gemert wrote:

enblethen wrote:
Transfer switch, shore power relay.
Locate model number and post.

X2, 2 relays in the transfer switch. One for shore power and one for genny power. If you are comfortable working with electrical components you may just be able to clean the contacts on the relay. Make sure all connections are tight first though. Good luck.

I agree, but I might also add to ensure that all power is isolated before working on any relay contacts or electrical devices. Electricity is very unforgiving. JMO

My transfer switch clicks when it engages and buzzes when plugged into shore power. The click is the relay pulling in and the buzz is a 60cycle hum. Most of them buzz and operate perfectly normal. Unless there are other problems associated with it, or it's just unbearable to hear, I wouldn't worry about it.

2 OTHER TID BITS OF INFO
previous owner of it probally 8 years probally never used shore power, just gen
2nd Im using a power cord reducer from camping world 50amp to standard plug 15amp.
I only want to plug in to keep batteries topped off and run lights inside maybe while doing stuff inside.

thanks ....... the buzzing is loud, hard to believe it would be an ok noise

Buzzing in the relays can be a couple of things.
Loose mounting
Loose connections
Loose coil mounting.
Depending on make and model of transfer switch, relays can be fairly inexpensive. Complete transfer switch are not always inexpensive.

Thanks I'll look around and report back

Is there a transformer in it Xtransfer switch. It could be loose laminations.

There is no transformer but the coils are constructed in the same manner and can delaminate. More apt to be loose.

The transfer switch on our 2013 Winnebago Adventurer was noisy. It was hard mounted to the storage cabinet wall. I stopped at Lowes and bought several rubber washers about 1/4" thick. I loosened all the mounting screws and removed them one at a time. With a screw removed and the remainder loose I slipped a washer between the switch box and the cabinet wall, then replaced the screw. When all the washers were in place I tightened all the screws. No more noise transferring through the cabinet into the coach.

Glad I don't have a transfer switch and am still at a loss for what they're good for, as there are better places for spending money.
Just something else to go wrong IMO.

Rap the automatic transfer switch box with your hand. It might quieten it down if that's what it is. Mine buzzes like that sometimes.