RCD testing device CP501

loop impedance

With over 2 million of these socket testers sold, the Martindale CP501 is the most popular socket tester available. The classic check plug is a quick and easy way to ensure that 13A sockets are correctly wired, indicated by 3 bright long life LEDs. 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