I purchased a Progressive Industries HW50C (hard wired)after I lost two of my three air conditioners while on shore power at a campground. After the fact I discovered I was not the only one who lost equipment. I’m still not sure whether the problem was low voltage or a power surge. The weather was hot and thunder storms were frequent, may it was both?
I have since had the HW50C disconnect me from power twice in similar conditions. I would not be without a HW-50C, I view it as cheap insurance.
Recently I purchased a 50 amp Hughes Auto-former (portable) to boost low line voltage at campgrounds. The Auto-Former prevents the HW-50C from disconnecting the coach when the line voltage drops. Last weekend, during a particularly hot day, I noticed the line voltage shown on the HW50C was down to 107volts, the power is disconnected at 104. I plugged in the Auto-Former and watched the voltage increase to 118 volts. Also cheap insurance.
50ft Kingsley Coach Custom, towing GMC Crew Cab