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Standard GU10's are brilliant at it!
new house electrics
- Thread starter Paulg31
- Start date
I don't doubt it, but I count them as incandescents, and don't use them. Anything with a filament is pretty likely to have (very brief) very-high-current 'death throes', often enough to trip and MCB!
Kind Regards, John
Well be don't know the OP's choice of illumination.
But given the amount of spare B6's in that board, I would split them.
But given the amount of spare B6's in that board, I would split them.
True.
... and be happy with the fact that switching off one of the MCBs could then leave bits of the corresponding circuit potentially 'live'?
Kind Regards, John
How would the other become live ? What conditions would have to exist ?
As I said, what is colloquially called 'borrowed neutral' can, in practice, be a 'borrowed line' (either will result in trips if the two circuits are on different RCDs). These situations usually exist when there is 2-way light switching and either neutral or line for one of the lamps is taken from the other circuit, usually because of the convenient proximity of a suitable cable.
Kind Regards, John
And if you have 2 lighting mcbs on the same rcd, why is there a shock risk ?
If there is a 'borrowed line' and you switch off just one of the MCBs (e.g. to do work on the corresponding circuit), some parts of the circuit will still be getting 230V via the other MCB.
Kind Regards, John
Yes ok. If you went disconnecting the neutrals you could get a shock.
I thought the guidance was that you should isolate both conductors before working on the circuit? (Flip the rcd)
I thought the guidance was that you should isolate both conductors before working on the circuit? (Flip the rcd)
Not only that. Even without disconnecting anything, there could be a live conductor at one of the switches on the 'switched off' circuit - which would be a hazard (L-E shock) whether or not the neutral were disconnected.
As above, isolating the neutral to the circuit in question wouldn't necessarily help. If both circuits were on the same RCD (as they would have to be) and you 'flipped the RCD' that would obviously make things safe - since the L feed to both circuits would thereby have been disconnected. In passing, as far as the regs are concerned, isolation of neutral is not necessary in TN installations.
Kind Regards, John
Not only that. Even without disconnecting anything, there could be a live conductor at one of the switches on the 'switched off' circuit - which would be a hazard (L-E shock) whether or not the neutral were disconnected.
i don't agree with that.
The neutral supply to the isolated circuit has to be disconnected.
i don't agree with that.
The neutral supply to the isolated circuit has to be disconnected.
There's a splendid article with diagrams in the Wiki explaining the problem.
Ban. You know no one reads the wiki.
And I would much rather derive the problem from first principles, so I can learn how the circuit works.
And I would much rather derive the problem from first principles, so I can learn how the circuit works.
Well - create yourself the problem, and learn how it can bite you then.
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