Called out to elderly couple's house today - no power. All 3 lighting circuit breakers are tripped and mainswitch is off. Quick check reveals PIR lightswitch faulty and 1 lamp failed. Replaced the PIR switch for standard 1G2W switch and reset everything, seems fine now. Question is, how did mainswitch end up off? See pic for setup. The old guy is a retired engineer and is becoming 'confused'. He has added PIR switches all over the place and other 'mods'. I'm thinking most likely he has switched it off but wife swears blind he hasn't. Have recommended EICR. Mainswitch is BS5419 and seems fine, resets to ON against slight spring pressure but doesnt seem worn. Just to satisfy my slight doubts, this is just a mainswitch right? can't trip under fault conditions? I have googled and have come across plenty of these before and have never known one to fail in this way if indeed it has failed. Any chance the recoil of 3 tripping mcb's could throw the switch? seems unlikely to me..also seems odd that all 3 would trip for single circuit fault. Anybody come across anything similar?
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