Changing direction of cable routing

[JohnL79]

Or come from the FCU horizontally and then turn 90deg up to the extractor?

 

[LoveRocket]

OK, fair enough, Banal.

So, if you are correct, GaryMo's solution is not acceptable either?
In fact, if you are correct, there's NO WAY to have an accessory hidden behind a decorative fake extractor chimney (for example), because it's not possible to route a concealed cable to it?

 

[Snark]

Or come from the FCU horizontally and then turn 90deg up to the extractor?

Thanks - I nearly persuaded myself that that might work, but I think that would still give me the same problem of having a cable route with one length (the vertical one in this case) whose position wouldn't be flagged up when the hood's in place.

 

[skenk]

No - it's not still true. If you can't see the accessory than the zone it creates disappears too...

Got a reg for that?

 

[ban-all-sheds]

Got a reg for that?

522.6.6.



Possibly......

 

[ban-all-sheds]

OK, fair enough, Banal.

So, if you are correct, GaryMo's solution is not acceptable either?

If.

I'm wondering though if what I wrote was b****cks.

In fact, if you are correct, there's NO WAY to have an accessory hidden behind a decorative fake extractor chimney (for example), because it's not possible to route a concealed cable to it?

It's not just cooker hoods where you have problems - what happens about wall lights, for example?

OTOH, it's easier to accept a zone the width of a wall light.

522.6.6 says "Where the cable is connected to a point, accessory or switchgear on any surface of the wall or partition, the cable may be installed in a zone either horizontally or vertically, to the point, accessory or switchgear."

Clearly a cooker hood is neither an accessory nor switchgear. But is it a "point"? If you've got a pitched canopy over a range cooker it could be 1m wide, or more, and over 1m high (from the lower surface to the ceiling. There's no guarantee that the cable runs to a location behind the fake chimney, it could be anywhere that's covered by the canopy and chimney.

So are we all happy that a hood like that creates zones in which cables can be concealed that are 1m+ wide, running from floor to ceiling, and over 1m deep running across the entire top half of the wall?

Remember, the zones run horizontally and vertically, it's not absolutely clear if the regulations only require the cable to be somewhere in the zones, i.e. not necessarily that the cable has to also be horizontal/vertical.

I hadn't thought about this up until now - I plan to run the cable to my canopy in a length of steel conduit with a round box at the end, positioned where the cable entry point is, so the zones aren't an issue for me.

But maybe that is the only way it could legitimately be done? I'm certainly not happy with the idea that it's OK to bury cables anywhere in zones that look like this:

 

[spark1]

gary you say
Do you think there needs to be after reading 522.6.6 (v)?

well this reg. advises on cable installation routes and methods..if I ,an experienced electrician ,decide after careful consderation to drill into the 150mm zones what Regulation is being broken?

..by the way I did it again today.

dont get me wrong i agree with the need for safe zones vertical and horizontal but the 150mm zones are in my opinion ill thought out in practical installation terms.

 

[skenk]

No - it's not still true. If you can't see the accessory than the zone it creates disappears too...

Got a reg for that?

522.6.6.

No mention whatsoever of being able to 'see' the accessory???

I'm wondering though if what I wrote was b****cks

What about under-counter outlets, don't they create zones? If you put a bed in front of sockets do they stop making zones!?

With a cooker hood it is often possible to put an accessible flex outlet somewhere behind the hood or chimney panel creating it's own zones.

 

[ColJack]

given that an accessory on one side of a wall creates a zone on the reverse side of that wall as well, being able to see it probably isn't a requirement..

is this going to be a naked wall besides the cooker hood?
if not then an FCU above the cabinet to either side of the hood won't be seen from below but will create a horizontal zone you can run in..

 

[ban-all-sheds]

No mention whatsoever of being able to 'see' the accessory???

The final part of 522.6.6 (v)?

But it makes the whole thing a nonsense if you can't.

Would you think it OK to use a flush box set back far enough to allow a flat blanking plate to be below the surface of the wall, and then plaster over the whole lot? The accessory is still there, you just can't see it. But that doesn't make the zone disappear too?

What about under-counter outlets, don't they create zones?

Maybe they stop at the point where a fixed object, like a worktop or a cupboard prevents you from seeing the accessory?

Imagine the following scenario. Someone wants to run a concealed cable up the wall, from below the floor to above the ceiling. He suggests that in order to create a safe zone he'll put a box + blanking plate part way up, but in order not to make the thing look untidy he will position the box + blanking plate where it will be covered up by a cupboard screwed to the wall.

OK, or not OK?

If you put a bed in front of sockets do they stop making zones!?

Is there not a difference between an item of movable furniture and something fixed to the wall?

With a cooker hood it is often possible to put an accessible flex outlet somewhere behind the hood or chimney panel creating it's own zones.

But what if you then conceal the flex outlet?


Take a step back and look at it all logically, from first principles.

Why do we have "safe" zones? What are they for?

They are there, surely, to provide a known route for cables to be buried. We want cables to be buried for cosmetic reasons, and we want the routes known so that we don't drill into the cables by mistake.

So - we say "where there is an accessory there are zones extending horizontally and vertically". So when you see the accessory you can tell where the zone is.

Note that the concept of needing to be able to see the accessory in some circumstances is recognised by the final part of 522.6.6 (v).

But if the position of the accessory is not known, because it too has been concealed by a fixed object, then the positions of the zones are also unknown, and I suggest that if you don't know about the existence of a zone then you haven't actually got one, because it no longer does the only thing it is supposed to do.

 

[ban-all-sheds]

given that an accessory on one side of a wall creates a zone on the reverse side of that wall as well, being able to see it probably isn't a requirement..

"Where the location of the accessory, point or switchgear can be determined from the reverse side, a zone formed on one side of a wall of 100 mm thickness or less or partition of 100 mm thickness or less extends to the reverse side."

How would you determine the location if you didn't know where the accessory was? That requirement, surely, means (for example) that if you know there's an accessory Y mm from the ceiling and X mm from the doorway you can determine where it is on the other side of the wall.

If you don't know that there's an accessory Y mm from the ceiling and X mm from the doorway because it's been concealed then you cannot determine its position, and therefore the zone does not extend to the reverse side.

So that's an explicit example of where not being able to see the accessory means you don't have a zone.

But in general terms? If you don't have a visible accessory then you have no knowledge of any zones, and given what zones are for can you be said to have one if you have removed the evidence of it's existence?

The zones aren't painted on the walls, they are imaginary, i.e. you are supposed to imagine their presence given the presence of accessories. If you conceal the accessories and thus prevent people imagining the existence of the zones do the zones still exist?

 

[holmslaw]

..

 

[ban-all-sheds]

The safe zones are very unsafe and have been invented by moronic members of the IET totally devoid of common sense.

Be that as it may, they are defined, and anybody who takes the trouble to find out can find out.

And always remember you are not allowed to run cables behind skirting boards either horizontally or vertically ie ANY cable behind a skirting board does not comply with the regs. Therefore the only acceptable way to wire is from high level to low level thus avoiding skirting boards.

So does a zone below a socket disappear if part of it is covered up by a strip of decorative wood?

Assuming I wanted white painted skirting, what if I had a gap in the skirting where the cable was, and filled it in with plaster which I carefully moulded to look just like the skirting and then painted?

The cable would not be behind the skirting, but what would be the difference?

Why do you say that you are not allowed to run cables behind skirting boards either horizontally or vertically even if there is a zone there?

Does BS 7671 define the term "skirting"? When does "skirting" become tall enough to be classed as "panelling"? Are you allowed to run cables behind panelling as long as they are in zones created by accessories?

Does the 150mm corner zone stop at the top of the skirting?

I'm not sure you're right on this one....

 

[GaryMo]

gary you say
Do you think there needs to be after reading 522.6.6 (v)?

well this reg. advises on cable installation routes and methods..if I ,an experienced electrician ,decide after careful consderation to drill into the 150mm zones what Regulation is being broken?

..by the way I did it again today.

If you drill into a 150mm 'safe zone' then you risk drilling into a cable of some sort. That's about it really, though to be honest, it's a possibilty no matter where you drill as I guess we've all witnessed totally random routes to accessories.

 

[holmslaw]

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