LOAD CIRCUIT PROTECTION DEVICE

摘要

Disclosed is a load circuit protection device which is comprised of a temperature estimation unit for estimating the temperature of a wire based on an artificial temperature calculation equation, and a cut-off controller which cuts off a switch when the temperature estimated by the temperature estimation unit reaches the tolerance temperature of the wire. The artificial temperature calculation equation is set by assigning a smaller artificial thermal capacity than the thermal capacity of the wire for the thermal capacity, and by assigning a larger artificial conductor resistance than the conductor resistance of the wire for the conductor resistance, in a wire temperature calculation equation which uses the elapsed time measured by a timer, the current detected by a current detector, and the thermal capacity and conductor resistance of the wire.