Why can't twin & earth be run diagonally?

[jimmyn197]

I've been left with a bit of a mess by an electrician. He came in & put a hole in my brick work (which I've now fixed) and didn't chase the twin and earth into the wall. I thankfully didn't pay him a penny & he's never asked for it (I think he knows he ****ed up) but he also isn't willing to come back & fix it.

My next job is to chase the twin and earth into the wall, the only issue is the twin & earth is connecting to something to the bottom left of the plug socket it's coming off. Meaning I was planning on just running it diagonally downwards but I've read twin & earth can only run horizontally & vertically. Why is this?

 

[martygturner]

well its stop people inadvertently drilling into the cables...see.. https://flameport.com/wiring_regulations/BS7671_selected_subjects/zones_concealed_cables.cs4

 

[ericmark]

Surface clipped any direction you want, buried unless armoured cable it needs to follow safe routes. So one can if you wish have it diagonal as long as you can see it is cable.

Also any buried cable also needs RCD protection.

Also if from a ring, it must be 2.5 mm and supply only one BS1363 item be it a socket or fused connection unit. So it has some where a 13 amp fuse.

 

[jimmyn197]

Surface clipped any direction you want, buried unless armoured cable it needs to follow safe routes. So one can if you wish have it diagonal as long as you can see it is cable.

Also any buried cable also needs RCD protection.

Also if from a ring, it must be 2.5 mm and supply only one BS1363 item be it a socket or fused connection unit. So it has some where a 13 amp fuse.

I like the surface clip idea but the only issue is it's going behind a splashback, so I could just recess it in a bit hide it behind the splashback (as no one will be drilling into that) and I won't plaster over them.

The cable has RCD protection & it goes to just a fused spur with a 3amp fuse as it's for a boiler.

 

[jimmyn197]

well its stop people inadvertently drilling into the cables...see.. https://flameport.com/wiring_regulations/BS7671_selected_subjects/zones_concealed_cables.cs4

Ah I see. I'll probably surface mount them behind a splashback as no one will drill into the splashback.

 

[hovertoast]

Surface mount is no longer surface mount if you cover it with splashback.

Concealing cables outside of safe zones is a foolish thing to do.

 

[flameport]

no one will drill into the splashback.

No one - except when they do to install a utensil rack and damage cables where they shouldn't be

which is the very thing which resulted in someone being killed

Experience: my wife was electrocuted

'A screw fixing the utensils rack to the wall connected with a live wire under the plaster and electrocuted her'

www.theguardian.com

 

[jimmyn197]

Surface mount is no longer surface mount if you cover it with splashback.

Concealing cables outside of safe zones is a foolish thing to do.

No one - except when they do to install a utensil rack and damage cables where they shouldn't be

View attachment 326146

which is the very thing which resulted in someone being killed

Experience: my wife was electrocuted

'A screw fixing the utensils rack to the wall connected with a live wire under the plaster and electrocuted her'

www.theguardian.com

Hmm, that's fair enough. Maybe the right thing to do is get this electrician back as I can't see how else I'll tackle this as he's put it in a really awkward position where it can't go vertically or horizontally (and I'm not too skilled with electrics if it wasn't already obvious)

 

[fixesthingssometimes]

Can you add an extra socket? So one in the legal place then go horizontal?

 

[ericmark]

Not sure what a plug socket is. If it is a new socket, then it must be RCD protected, I have quoted Emma Shaw's death many times, but today the RCD would trip first.

 

[sparkwright]

No one - except when they do to install a utensil rack and damage cables where they shouldn't be

View attachment 326146

which is the very thing which resulted in someone being killed

Experience: my wife was electrocuted

'A screw fixing the utensils rack to the wall connected with a live wire under the plaster and electrocuted her'

www.theguardian.com

Surely it could be argued that running a vertical cable within the width of that rack IS in a safe zone, as it has a very large electrical unit above it.

 

[flameport]

Appliances and current using equipment do not form cable zones. Only the point, accessory or switchgear.

For the benefit of those who wish to 'interpret' such things and waste the next 10 pages arguing over it, those three items are:

Point (in wiring). A termination of the fixed wiring intended for the connection of current-using equipment.

Accessory. A device, other than current-using equipment, associated with such equipment or with the wiring of an
installation.

Switchgear. An assembly of main and auxiliary switching equipment for operation, regulation, protection or other
control of an electrical installation.

Appliances and current using equipment are none of those things, whether they are fixed or portable.
Any zone would only be that formed by the FCU, socket outlet or other connection point, not the entire extractor assembly.

 

[sparkwright]

So, to keep it simple, where can you bury the wall a supply cable for the cooker hood if you aren't using an accessory such as an FCU?

I would imagine where you want the cable to emerge from the wall would have to form the cable zone, and that a junction box would be fitted - that is of course even if the unit does have a pre-fitted flex.

I would also imagine folk would have to dismantle things to determine where the cable may or may not run - something which many, many people would not do.

There will be other units, not necessarily cooker hoods, where the cable entry is nowhere near the wiring termination.

My thoughts (without making stuff up) are that the entire width and height of the unit should, or could, form a wiring zone, to deter people drilling there - only no one would be aware of such a rule even if it did exist.

Just thinking out aloud here - I have no strong opinions on this as such.

 

[ebee]

So, is an Electric Shower a point or an accessory or switchgear?
Are we allowed to have a buried cable behind it if it is not running in the zone of protection created by a switch/isolator for example?

 

[flameport]

So, is an Electric Shower a point or an accessory or switchgear?

According to the definitions it is none of those things.

The terminal block inside could possibly be considered a point for wiring termination, but that only makes the zone the same size as the cable.

The shower itself does not form a cable zone because it is current using equipment.