Transfer Switch Questions

Hit it with a rubber hammer if you have the room. It may "fix" the problem. Either temporarily or for a long time

Sometimes the transfer switches that appear to be integrated into the power center really just bolt on the back and are separately replaceable without too much difficulty.

As was mentioned, the exact construction does vary a bit with different models, particularly for 50A transfer switches, but in every case it will be based around one or more electromechanical contactors, possibly with some slight electronic control circuitry and often (in the case of multiple contactors) with mechanical interlocks to preclude the possibility of having more than one source active at any time. I don't think there are any purely solid state transfer switches around, at least not for RV use.

What is make and model of your transfer switch?
Different models function differently and vary on number of relays.
There is a recall on some Iota 50 amp transfer switches.

On our 30 amp it's just a double pole single throw relay with a time delay. Normally closed side is tied to shore power. Relay is activated when I crank the generator.

I will assume the 50 amp has 3 poles.

I replace ours this past spring. Relay was still working but had intermittent power when I wiggled the wire bundle. Found the wires to the relay had gotten hot and melting the wire nuts, burned the wire open, and burned an inch or so of insulation. Relay contacts were oxidized a bit so I decided to replace it.

Not sure when it happened as we didn't smell anything and everything worked fine until I moved the wire bundle during a solar installation. I think that during a previous electrical repair, the wire nuts were left slightly loose or the wires weren't clean and caused a high resistance.

There are two large electro/mechanical relays that have a printed circuit control board. The two relays are interchangeable/replaceable.