Insulated tails used to supply flats

It's very early..but..reading the article again does it mean putting cables deeper then 50mm is a method of protection still?

I'm not to sure it does, it's a bit ambiguous .

OK, I'm  now near a copy of the 18th, and of course the actual thing is a bit wordy, so apologies for the block quote but '202  is clearly only for cables less than 50mm from surface, anything more than 50mm deep is out of scope and can be routed how you like -

however '203 which is for partition walls made with metal framework, sensibly does not have thick walls as a protection, as the wall will bring any voltage from a buried fault to the surface,and such partitions often have sharp metal edges internally that can snag a cable.

Hope this helps.

522.6.201 A cable installed under a floor or above a ceiling shall be run in such a position that it is not liable to

be damaged by contact with the floor or ceiling or their fixings.

A cable passing through a joist within a floor or ceiling construction or through a ceiling support (e.g. under

floorboards), shall:

(i) be installed at least 50 mm measured vertically from the top, or bottom as appropriate, of the joist or batten,or

(ii) comply with Regulation 522.6.204.

522.6.202 A cable installed in a wall or partition at a depth of less than 50 mm from a surface of the wall or partition shall:


(i) be installed in a zone within ISO mm from the top of the wall or partition or within ISO mm of an angle formed

by two adjoining walls or partitions. 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. 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 l 00 mm thickness or less or partition of

l00 mm thickness or less extends to the reverse side, or


(ii) comply with Regulation 522.6.204.

Where indent (i) but not indent (ii) applies, the cable shall be provided with additional protection by means of an RCD having the characteristics specified in Regulation 415 .1.1.139
522.6.203

Irrespective of its buried depth, a cable concealed in a wall or partition, the internal construction of which includes metallic parts, other than metallic fixings such as nails, screws and the like, shall:

(i)

be provided with additional protection by means of an RCD havi ng the characteristics specified in Regulation 415.1.1,or

(ii) comply with Regulation 522.6.204.

For a cable installed at a depth of less than 50 mm from the surface of a wall or partition the requirements of  Regulation 522.6.202(i) shall also apply.
522.6.204

For the purposes of Regulation 522.6.20 I (ii), Regulation 522.6.202(ii) and Regulation 522.6.203(ii), a cable shall:

(i) incorporate an earthed metallic covering which complies with the requirements of these Regulations for

a protective conductor of the circuit concerned, the cable complying with BS 5467, BS 6724, BS 7846, BS 8436 orBS EN 60702-1 , or

(ii) be installed in earthed conduit complyng with BS EN 61386-2 1 and satisfying the requirements of these

Regulations for a protective conductor, or

(iii) be enclosed in earthed trunking or ducting complying with BS EN 50085-2- 1 and satisfyi ng the requirements of these Regulations for a protective conductor, o r

(iv) be provided with mechanical protection against damage sufficient to prevent penetration of the cable bynails, screws and the like, or

(v) form part of a SELV or PELV circuit...

Also note that if we didn't have the 50mm rule (or something similar) then a cabled chased into a wall on one side would also be considered to be concealed within the wall when looking from the other side as well - and so would have to be within zones w.r.t. that side of the wall too - which probably isn't exactly convenient if you didn't particularly want accessories in the same position on both sides of the wall. Note the exception for walls less than 100mm thick when you can readily see both sides - such an approach would be tricky for things like party walls where you don't have access to the other side.

   - Andy.

Of course if you drill right through the party wall you do rather deserve to get into trouble.

Sometimes it is not the electricians fault

scroll down pretty pics of a party wall issue that is not wiring

I think the article I quoted adds to the ambiguity a bit, it mentions RCD and armored cable/metal conduit as methods to protect cables but fails to add that the >50mm cable depth in a wall is still considered suitable protection against cable damage.

Is the wording in the latest OSG any clearer?

It may be electrically sound and not actually break any  regs but it certainly earns no prizes for beauty or quality of workmanship.

Also things that are that rough on the surface make you wonder about the quality of all the bits you cannot see, have they remembered fire stopping  in ceilings and and holes in joists in the right places  for example?

Untidy, so not good workmanship. I would check all the tails screws in each switchfuse, because I bet they are not tight, particularly as the ties were probably added after closing up! What does the EIC say, who is responsible, no reason not to publish it!

It would be usual to have the switch fuses in the same room as the meters, and certainly within 3m cable length of them. Where are the meters? 


Regards,


Alan.

It's a horror installation,  the other side of the wall is the main intake, all tails are bunched and hanging in cable ties, supplier cable laying on the floor! It just under 3m length on the tails.


The switch fuses have had the covers so badly cut you can get your finger in there. The board they are fixed to is falling off the wall. I honestly thought they were temporary supplies when I saw this!

the earth cables are jointed with a floating connector block in the switch fuse covers, these look to be rated at no more then 30A.

We may end up going the legal route as the automatic fire smoke vents fitted and fire shutter are illegal and the main contractor is denying liability so I'll keep their details anonymous for now. It's a national home builder though....