Patent ID: 7788055

Claim:
A method of calibrating a circuit breaker having a signal chain including a current transformer, a burden resistor, a stored energy circuit, and a controller, the circuit breaker including a memory coupled to the controller, the method comprising: writing a calibration instruction routine in a first location of the memory; connecting a current injector to the current transformer; injecting a test current into the circuit breaker signal chain at a high temperature by the test current injector, the test current having a test current peak; measuring the test current peak of the test current in the circuit breaker signal chain via the controller; storing test current peak data indicative of the test current peak in a second location of the memory; reading the test current peak data from the second location of the memory via a communications interface; comparing the test current peak data with nominal current data related to the test current; determining a calibration factor based on the comparison; creating, by the controller, a specialized calibration table based on the calibration factor and a nominal template modeled from the current transformer; and writing the specialized calibration table to the second location of the memory.