I've had 3 campers. I always keep my TT's plugged into shore power all the time... but ... there have been a few exceptions when I've forgotten to plug them in, especially in the winter when shoveling snow or snow plowing the drive where the cord crosses. Anyway, bottom line is, I have on occasion allowed my TTs house battery go without charging, and when the battery gets so low, the converter inside (the main electric panel) in all 3 campers beeps! The firs time this happened, it took forever to figure it out. Plugged shore power back in and it quit. It's possible the occasional beep is because your house battery is low and your converter is trying to let you know.