Wiring faults are indicated by one or more of the LEDs failing to illuminate, with the pattern of lit LEDs indicating the type of fault detected. This fail-safe system means that any LED not lit indicates a fault. The robust ABS housing has a sculpted shape for easy removal and there is a look up chart on the tester for quick fault diagnosis.

The plug induces less than 5mA of earth leakage, well below RCD trip thresholds.