Thom,
Your top picture is the transfer switch. Your second picture is the generator control box.
I could not find a wring diagram of the transfer switch but it is just the two contactors and a single relay. The idea is that the power fed to the AC panel is by default feed from the generator, unless there is voltage present on the shore power side. If there is the contactor closes (after a few seconds) and one contactor opens and the shore one closes.
I attached a pic of mine. Same setup, yours has semen’s contactors and mine has Eaton. Yours is arranged in the box better, as you can not see the relay which is under the large power wires on mine.
Hope you got this fixed by now, if not any electrician should be able to change the relay.
Transfer Switch
Relay behind the wires
Joe and Becky Carter
Aiken SC
1993 Prevost LeMirage XL with 8V92TA and Allison HT 755CR
1994 Angola Conversion
2007 Jeep Liberty Toad
joe81au at gmail.com