A method for testing low voltage power circuit breakers having an electronic trip unit which includes a display and a microprocessor for controlling various protective functions and storing settings for such functions which can be selected and performed. Entering into the test mode disables functions not necessary for the testing to be performed. A current is injected into one of the phases of the breaker. The technician observes whether the breaker performs within the specifications for the selected protective function. Upon exiting the test mode, the breaker is automatically restored to the settings prior to the testing.