Plugging into shore power.... Buzzing noise

We have had a noisy transfer switch also. We noticed this especially after running the generator and switching back to shore power. Make sure there is nothing on when you plug in. No large draw right when you start like frig that will switch automatically from gas to electric, AC with setting low enough it kicks on right away, etc. When it happens, sometimes we shut the main circuit breaker off, wait a minute and flip it back on and buzz will go away. We also noticed it seems to be worse in cold weather. Just something we have learned to live with at times. Ours is random.

On our last motorhome, a 2003 Cross Country, it had a loud buzzing sound when plugged into shore power. It was a noisy transfer switch. The dealer replaced it three times before getting a quiet one.

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.

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

With gen ..... No noise

Could be transfer switch issue.
Start genset and see if it the same.

There's not a chance this could be normal. I jumped back waiting for it to go boom. All that's there is the shore wire and a black box. I pulled the black box cover off and it's just where all the wire connect. It says gen wires come in, shore wires come in and one set of wires go out to motorhome. I think the converter is on the other side of coach where batteries are.

We have a 2001 with a Trace 2000 watt inverter. Yes it does buz. I think it's more of a hum. Not to worry.

Converter

Motorhome is a 1999 holiday rambler 40' class A diesel