A load circuit protective device calculates increasing temperature of wire of a load circuit with a first predetermined sampling period determined by a clock signal for normal operation when a semiconductor relay is on to estimate the temperature of the wire. The cams apply a force to the piston by way of a lifter for providing mechanical advantage so that a smaller motor may be used to rotate the cam. The core chips each include a plurality of memory arrays. The control unit is electrically connected to the first and the second AC switch units which may be turned on and off thereby to control the first and the second inductors which charge the input currents and discharge the input currents to the first and the second storing devices.