The transfer switch is a black, plastic box which is usually located high on the bulkhead that separates the front genny/battery compartments from the basement. I have surge protection in our coach and it can take upwards of three minutes for the transfer switch to "see" loss of normal/utility source and switch over to the generator. Sometimes, you almost think it's not working but it eventually switches over.
2012 F350 KR CC DRW w/ some stuff
Cindy and Tom, Toby and Kasey (our Berner and Newfie)
Oh...I forgot the five kids.