RV Surge Protector 30A\120VHigh/Low Voltage Protection: Whenever AC power falls below 104 Volt, or rises above 132 Volt, the EMS automatically shuts down power to the RV. The EMS will monitor the power and once the AC power rises above 104 Volt, or below the 132 Volt level, the time delay indicator flashes for the preset time and then automatically restores power to the RV. Time Delay for A/C Compressor: If the AC power is interrupted, or the EMS detects a fault condition, the built-in time delay is activated. A Built-In Lock Bracket allows the user to secure the EMS to power source to prevent theft.Portable Rv Surge Protector, 30amp 120V, provides total electrical protection of RV electronics and complete digital readout of the AC power source. Protects against high/low voltage problems, incorrect AC wiring, and power surges, while the built in display continually scrolls, showing line voltage, current, frequency, and error message. EMS shuts down power if AC source drops below 104V or rises above 132V, automatically restores it once power is between 104V-132V after 136 second delay. Power is also shut down if AC outlet is wired incorrectly, or 220V is detected on the 120V power line(s). The error message notes AC power condition. 30 amp models have surge rating of 1790 joules and 3-mode protection, 50 amp models have 3850 joules, and 4-mode protection. Surge light denotes condition of surge circuit. Portables models are weather resistant, and have a built-in theft device. Hardwired models include remote digital display and hardware.Features:Whenever AC Power Falls Below 104 Volt, Or Rises Above 132 Volt, The EMS Automatically Shuts Down Power To The RVIf The AC Power Is Interrupted, Or The EMS Detects A Fault Condition, The Built-In Time Delay Is Activated3-Mode Surge Protection: This Feature Provides Full Surge ProtectionFeatures Surge Indicator, Reverse Polarity Protection, Open Neutral Protection, Open Ground Protection, AC Frequency Protection, Accidental 240 Volt ProtectionWeather Resistant: Can Be Exposed To The Elements, However, May Not Be SubmergedMicroprocessor Controlled: The Computer Is Driven By A State-Of-The-Art Microprocessor That Is Programmed With Software To Drive The Entire EMSBuilt-In Lock Bracket: Allows The User To Secure The EMS To Power Source To Prevent TheftAutomatically Reconnects: YesWeight: 3.7500Voltage Regulation: 120 VoltAmpere Rating: 30 AmpUsed To: Protect From Damaging Low/ High Voltage Levels and Power Surges When Connected To AC Power SupplyWith Fault Indicator: YesWith Plug Head Handle: Yes