When the MOVs are intact, a surge protector clamps an over-voltage and shunts the excess to ground, passing clean power to the load. A lit protection indicator reports this state.
source-governedDiagnostic estimate. Not a quote, not a substitute for a licensed electrician.source pack dated 2026-06-20 · authority hashes pending
Where to stop. Swapping a plug-in surge strip is homeowner-safe. If the "Grounded" light is off, the receptacle itself may be ungrounded or miswired — confirm with a plug-in tester, and because correcting house wiring means live conductors, if a tester shows an open ground have a licensed electrician verify the outlet. This is general information, not a quote and not a substitute for a licensed electrician.
Electrical Fault Check provides general diagnostic information only. It is not professional advice, not a quote, and not a substitute for a licensed electrician. Do not work on live wiring. If you see smoke, sparks, burning smell, heat, shock, water exposure, or repeated tripping, stop using the circuit and contact a licensed electrician or emergency services as appropriate.