Progressive EMS-HW50C unit

Thanks to all for the input. It has given him an idea of something else to check. The power has and is at constant 118-122 V @61 H. Never showed error code and power never disconnected or dropped. The ATS was silent. Sound came from the Progressive EMS and you could put your hand on it and feel it. After reading your inputs and thinking back he says that just a few days before they had replaced the 30 amp breaker on the big generator. Now he wonders if the 50 amp breaker is getting weak. He (being Hubby) says breakers are not meant to be turned off and on constantly and these are turned off and on a lot because we have to check the generator fluid levels almost daily--we turn the breakers off before killing gen--after cranking the gen back up we turn the breakers back on so the gen does not crank up under a full load. Hmm we always turn everything off in the camper so maybe we should stop turning the breakers off since we are not really cranking the gen up under a full load!! BTW we have 50 amp in our camper. The sound has never returned. We may need to get our service guy to replace the 50 amp breaker at the generator. Think we will put our pantry back together and wait and see. Will check on contacts replacement. Maybe we should just bypass the EMS since we really don't need it here with our constant power source. We are totally running on the big generator; no shore power here.