Sorry but the best way for a safe installation is to employ an electrican.
Need to earth back boxes? Earth sleeves etc.
- Thread starter Draughtsman
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Sorry but the best way for a safe installation is to employ an electrican.
You're probably right.
Junction boxes and cable ends with insulation tape under the floor boards suggest a poor quality of install and/or maintainance,
The red taped ends are just markers, they're not connected to anything. They just highlight that these are the cables that already go through the wall and are therefore to take the power to the new circuit in the room over the old car port.
That junction box though, is a bit rough.
That junction box though, is a bit rough.
To what, and where, were you planning to connect your new sockets to the supply?
Do you have a set of calibrated test equipment that can measure
Continuity (low ohm meter)
Insulation resistance
EFLI tester
Other tests may be necessary depending on your answer to my first question.
Do you have a set of calibrated test equipment that can measure
Continuity (low ohm meter)
Insulation resistance
EFLI tester
Other tests may be necessary depending on your answer to my first question.
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So is the way that some cables are too close to the floor.
That whole area is a mess, and needs rectifying.
Then there's the issue of the testing which should be done on the new cables before and after making them live...
Rectifying! I see what you did there...
Those cables passing over the threshold brickwork and under the floorboards? How far down should they be?
The plasterboard ceiling shown is 4.5" below top of joist, the top of the ceiling plasterboard batens is only 2.75" below top of joist.
Those bricks in the top course have been cut, they're only half a brick deep, I could masonry drill off the end of one top brick and then use one of those drills with a 90 degree crank to get a fairly low hole thru the joist below those pipes?
The plasterboard ceiling shown is 4.5" below top of joist, the top of the ceiling plasterboard batens is only 2.75" below top of joist.
Those bricks in the top course have been cut, they're only half a brick deep, I could masonry drill off the end of one top brick and then use one of those drills with a 90 degree crank to get a fairly low hole thru the joist below those pipes?
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For cables as long as you get them 50mm below/above the surface where they're not free to move out of the way you'll be ok. Or you can protect them with steel plates but no one agrees what thickness is enough. Basically enough to stop casual drilling or screwing.
Just take out a vertical mortar joint beween two bricks, and put 2 cables thru that gap (the outer leaf stops a brick and a half lower so I could pass over the top) ? It would be almost 50mm below floorboard surface, I could put a steel plate over the top to cap it off. With a corresponding hole in the adjacent joist over the top of the battens..
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A functional Earth is not a protective conductor. It's all irrelevant though, as we were not discussing functional Earthing.
.... I think that some rather odd (incorrect?) things are being said in this discussion.
The premise seems to be that a "live conductor" is one that is 'intended to carry current during normal use' and, give or take some uncertainty about what 'intended' would mean, this can be taken to mean that a CPC can be considered as a "live conductor" (because, in some circumstances, it may carry {very small} currents during normal use).
However, that does not appear to be what the BS7671 definitions actually say. For a definition of "Live Conductor" one is referred to "Live Part" and that talks not in terms of a conductor (or other part) which 'is intended to carry current during normal use' but, rather which is "intended to be energized in normal use". "Energized" is not defined, but would you really say that we "intentionally energize" CPCs? For what it's worth, I wouldn't.
If the intention were that CPCs should be considered as "Live conductors", there would be quite a lot of implications (at least some of which would make little sense), because of various requirements in relation to live conductors. For example, isolation in a TT installation would then require isolation of the CPC - something which would be contrary to other regulations and arguably potentially dangerous.
I would therefore suggest that, attempts on the part of anyone to 'be clever', aside, the generally-accepted view that CPCs are not 'live conductors' is both sensible and almost certainly the intention of BS7671.
Kind Regards, John
The premise seems to be that a "live conductor" is one that is 'intended to carry current during normal use' and, give or take some uncertainty about what 'intended' would mean, this can be taken to mean that a CPC can be considered as a "live conductor" (because, in some circumstances, it may carry {very small} currents during normal use).
However, that does not appear to be what the BS7671 definitions actually say. For a definition of "Live Conductor" one is referred to "Live Part" and that talks not in terms of a conductor (or other part) which 'is intended to carry current during normal use' but, rather which is "intended to be energized in normal use". "Energized" is not defined, but would you really say that we "intentionally energize" CPCs? For what it's worth, I wouldn't.
If the intention were that CPCs should be considered as "Live conductors", there would be quite a lot of implications (at least some of which would make little sense), because of various requirements in relation to live conductors. For example, isolation in a TT installation would then require isolation of the CPC - something which would be contrary to other regulations and arguably potentially dangerous.
I would therefore suggest that, attempts on the part of anyone to 'be clever', aside, the generally-accepted view that CPCs are not 'live conductors' is both sensible and almost certainly the intention of BS7671.
Kind Regards, John
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A Live conductor is one that has a potential different to the ambient ( Ground or equipotential "Earth" ) potential. it does not have to be carrying a current to be Live.
If the Neutral is to considered as Live conductor then any conductor connected to the Neutral will have the same potential as the Neutral.
Hence if the Neutral is to be considered as a Live conductor then the MET, CPC and all items bonded to the MET have to be considered as being Live as well.
As I said, if 'energizing' means deliberately connecting a conductor to such a potential, then that's what the BS7671 definition seems to be saying.
Quite - if the above is true, then so probably is this. However, as I said, it makes little sense in terms of some regulations - do you really think that it is 'intended', sensible or necessarily 'safe' to include isolation of the CPC in the name of 'isolation' (in TT systems)?
Kind Regards, John
That is really going to depend on the definition of "energise".
But when you intentionally supply something which in normal operation creates a potential difference between the cpc and true earth so that you intentionally cause current to flow in the cpc......
I'm sure it is.
So maybe those who claim a definition for "live conductor" which ends up making a cpc one should reconsider their definition rather than falsely claim that cpcs are not intended to carry current during normal operation.