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The neon that fails a good circuit0.22 megohms and the switch neon is lit. Fault?

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The question at the end: 0.22 megohms and the switch neon is lit. Fault? The answer is in the notes below.

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Cooker switches often have a neon indicator. Leave one in circuit and test line to neutral at 500 V, and the neon lights — and the reading collapses to something like 0.22 MΩ. A perfectly good circuit has just “failed”. The same happens with lamps left in a lighting circuit: they glow, and the reading drops.

Neon in circuit L–N at 500 V · the neon lights 0.22 MΩ looks like a fault · isn’t Joined in a block switch not fitted yet >900 MΩ the cable, proved
Know what’s on the circuit before you trust a low reading. A neon or a lamp is a path between line and neutral; the meter can’t tell it from a fault.
✋Switching it off doesn’t solve it. With the switch off, the cable beyond the switch isn’t tested — and the neon is often on the load side anyway. Most neons can’t be disconnected either. The answer is the two-stage test.
Lighting circuits: test before the lamps go in. Fifty downlights is fifty lamps to take out again if you fit them first. Your tests don’t prove the lamps work — that’s functional testing.

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