A protection and indication apparatus

摘要: A protection apparatus (48) is provided which in addition to protecting electronic equipment (5) from overvoltage transients also able provide an indication of whether or not said are due impedances associated with poor earthing. In one embodiment the includes input terminal (42), output (60) and a ground reference (62) transient blocking unit (50) arranged isolate response destructive voltages. gas discharge tube (46) conduct currents voltages earth connection point (62); indicator (58), such as fuse circuit breaker placed series indicate presence voltage resulting interaction earthing impedance.