Patent ID: 6788515
Filing Date: 2004-09-07
Classification: H02H

Abstract:
An over-current control device comprising:a step-down transformer; a rectifier for rectifying the output of the transformer; a time/current characteristic circuit wherein the time rate of voltage increase and decrease simulates the thermal characteristics of the time-to-melt in a fuse element and the time-to-reset in a circuit breaker, said time/current characteristic circuit being connected to the output of the rectifier; a minimum trip level circuit responsive to said time/current characteristic circuit and comprising a voltage-monitoring integrated circuit chip and a first switching device, wherein said integrated circuit chip transitions from a low output state to a high output state based on a threshold voltage level sensed at the input of the integrated circuit chip, thereby controlling said switching device; and a tripping circuit responsive to said minimum trip level circuit and comprising a second switching device, stored energy means and a latching relay, wherein said latching relay is controlled by said second switching device and is powered by said stored energy.