The UL Listed PowerKey AC Machinery Access Control System is designed to limit the access to powered devices to authorized users only. Power is supplied to the controlled device after a valid code has been entered. After the device has been switched off, PowerKey AC will sense the load reduction and begin a time out before restricting access. Once this time has expired, a valid code must be entered in order to supply power to the device again. PowerKey AC also monitors the circuit for an overload. If an overload has been detected, PowerKey AC will automatically shut down and the LED’s will begin flashing alternately to indicate the condition.