Dyer's 50 amp portable RV surge protector is designed to protect your RV's electrical system from the dangers of faulty electrical power. If the voltage level drops below 102V or rises above 132V it removes power. Once the voltage resumes, power is restored to the RV with a time delay to allow for AC head pressure bleed off. This unit will monitor for faulty wiring from the power pedestal and protects from reverse polarity and the dangers of an open neutral condition.