The handheld Megger DET20C ground resistance clamp tester can be used to test lightning arrestors to verify their condition to successfully dissipate the energy from a lightning strike.
The system is tested by clamping the spring-loaded jaws around the arrestor conductor and then inducing a current in order to make a direct measurement of the resistance to ground.
The instrument can also be used for general earth testing of multi-grounded systems as well as to measure leakage current.
Test results can be stored in onboard memory and downloaded to a computer if required. Fixed-interval measurement logging is also possible.