A system for testing electrical power circuits in a home or office building includes a circuit breaker tester unit having circuitry which is electrically connectable to a circuit breaker panel and which monitors the service voltage provided to the circuit breaker panel and the current and voltage measurable on the outputs of circuit breakers within the circuit breaker panel under no load and load conditions, a portable outlet tester unit used for testing the proper connection of the wiring in the home or office building to which power outlets therein are connected and a load bank having test loads capable of being selectively switched into electrical communication with the output of a respective circuit breaker residing in the circuit breaker panel in order to test the operability of the respective circuit breaker in the panel.