The AVS13is an Automatic Voltage Switcher rated at 13Amps and the AVS15 rated at 15Amps. TheAVS will switch off The equipment connected to it if the mains power go outside Preset acceptable limits and will re-connect -automatically When the mains power teturn to normal. Re-connection takes Place after a delay to ensure stability of the mains The standard Delay on the AVS 13 is 1 minute, and 3minutes on the AVS15. If The delay period must be adjusted then contract your dealer. In Addition to the above protection, the AVS13RL includes RFI (Radio Frequency Intereference) suppression and Extra Spike And Surge Capability. Thus, the AVS13RL provides protection Against over-voltage. Under-voltage, power-back surges, spikes, Lightning & RFI.