The Martindale Buzz-It features and audible indication of the correct wiring status of sockets, making it ideal to use in awkward areas. Three bright, long-life LEDs also illuminate to show the wiring is correct, therefore if there is no sound and any LEDs are unlit, you know there is a fault. Faults are easily identified by the pattern of the lit LEDs.
With the audible indication, the Buzz-It can also be used as a basic fuse finder, when the correct fuse is pulled the buzzer stops.
Note: Like all other standard socket testers, the Martindale CP501 will not detect common earth and neutral or earth neutral reversal.