CIRCUIT BREAKER AND METHOD FOR SENSING CURRENT INDIRECTLY FROM BIMETALVOLTAGE AND DETERMINING BIMETAL TEMPERATURE AND CORRECTED TEMPERATURE DEPENDENT BIMETAL RESISTANCE

摘要

A circuit breaker includes a bimetal electrically connected in series with separable contacts, and an operating mechanism structured to open and close the contacts. A temperature sensor distal from the bimetal includes an output having an ambient temperature signal. A trip circuit includes a first circuit having a first input electrically interconnected with a bimetal output to input a voltage representative of current, a second input electrically interconnected with the temperature sensor output to input the ambient temperature signal, a real-time thermal model structured to provide a corrected temperature dependent bimetal resistance as a function of the voltage and the ambient temperature signal, and an output including a current value which is a function of the ambient temperature signal and the corrected bimetal resistance. A second circuit includes an input having the current value and an output structured to actuate the operating mechanism in response to predetermined current conditions.