Load shedding relay/contact in generator panel.

[General Lee]

Just got a 20KW automatic standby generator installed. A contact or relay (which ever you wish to call it) was installed for the Hot water tank. This contact will shed the load from the water heater in the event the genny starts to get over loaded. The relay is in the new sub panel and I noticed it is constantly "Humming" like a light ballast does. I'm told it is normal and the electrician is coming out in the morning to do the first start up and test runs. He's going to check it out but stated they switched to a new brand that is much quieter (Which I have). The old ones they used were clacking like a old pick up truck.

My question is, is he correct in that slight humming is normal? I'm new to this kind of generator set up and have never heard a fuse panel hum in my entire life. What do you knowledgeable folks say about this?

 

[cqaigy2]

Don't know about your humming problem, but i sure like the idea about load shedding.