chasing in electric cables

[bassmonster]

what type of housing do i need to use to chase in electric cables into the wall? can i use plastic or steel?

 

[Pensdown]

I'm trying to understand your question.

I'm assuming you're asking what type of capping do you need to cover the cables you have just chased in?

If you have run the cables within the approved zones then you can use plastic. If you have run the cables outside of the approved zones then you must use steel. In this instance the steel capping must be earthed.

Mots of us agree that oval conduit is better than capping but it's your choice.

 

[bassmonster]

sorry for not being clear. I basically want to insert the cables into the wall as currenlty they are housed in trunking above the surface of the wall.

 

[Cristino]

ignore! misunderstood the question

 

[BJS_Spark]

If you have run the cables outside of the approved zones then you must use steel. In this instance the steel capping must be earthed.

Steel capping will not protect cables run outside of the zones. You would need to use earthed metal conduit or go to 50mm deep outside of normal zones.

 

[Adam_151]

IIRC (becuase I can't be arsed to dig out my regs from somewhere on my desk under all the papers) they say something about an earthed metal covering suitable for use as a cpc, this can clearly aply to pyro and SWA, but would you use capping as a cpc?....

I am however a fan of earthing capping in zones

 

[Qedelec]

The main use of capping is to protect the cables from the plasterers trowel. Regs allaw cable to be unprotected as long as they are run horizontally or vertically from an accessory.

 

[ban-all-sheds]

sorry for not being clear. I basically want to insert the cables into the wall as currenlty they are housed in trunking above the surface of the wall.

http://www.niceic.org.uk/downloads/C5-43.pdf

http://www.niceic.org.uk/downloads/concealedcables.pdf

http://www.iee.org/Publish/WireRegs...les_concealed_in_thin_walls_or_partitions.pdf

 

[Pensdown]

If you have run the cables outside of the approved zones then you must use steel. In this instance the steel capping must be earthed.

Steel capping will not protect cables run outside of the zones. You would need to use earthed metal conduit or go to 50mm deep outside of normal zones.

Earthed steel is not there to protect the cable it's there to put an earth fault on the system if a nail goes through it into the cable.

Hey Qed, good to see you back. I hope everything's rosy in your garden and you're spending your first million wisely

 

[bassmonster]

thanks for the info guys. i've bought plastic conduits which will house the cables

 

[ban-all-sheds]

So they will all either be in recognised zones, or more than 50mm deep, will they?

 

[homespark]

Earthed steel is not there to protect the cable it's there to put an earth fault on the system if a nail goes through it into the cable.

Sure enough, this is a good idea, but (imo) not a requirement of the regs. Plus, it's a fiddly enough job installing metal capping without having to earth it too! If it's installed within the zones, then someone whacking a nail into it is being very careless. What if it was plastic capping? Then they would not have the benefit of any earthing, other than the CPC. Or, say it was just PVC/PVC embedded in plaster (allowable, but not recommended).

I'm only going on about this, as I recently installed metal capping (unearthed) for a minor works job as part of my NICEIC assessment, and am hoping I didn't get it wrong! I used metal instead of plastic as It offers better mechanical protection.

 

[BJS_Spark]

Earthed steel is not there to protect the cable it's there to put an earth fault on the system if a nail goes through it into the cable.

It is there for protection as said previously from plasterers trowel, but you still can't use it earthed outside the zones as protection from nails or other puncture, which is how your post read.

 

[Pensdown]

522-06-06

i) incorporates 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 bla bla bla

iii) be enclosed in earthed conduit, trunking or ducting satisfying the requirement of these regulations for a protective conductor OR be mechanically protected sufficient to prevent penetration of the cable by nails and screws and the like.

iv) be installed in a zone bla bla bla

In summary, if you can mechanically protect the cable to prevent penetration by nails and screws etc, the protection does not need earthing even if its a metallic material. However, a nail gun will penetrate most materials including steel conduit so section (i) or paragraph 1 of section (iii) would normally be adopted.

Although not ideal, earthed metal capping complies with 522-06-06. Earthing the capping is pretty straight forward using a pop rivet and a short fly lead of cable with a ring crimp on one end

 

[homespark]

In summary, if you can mechanically protect the cable to prevent penetration by nails and screws etc, the protection does not need earthing even if its a metallic material. However, a nail gun will penetrate most materials including steel conduit so section (i) or paragraph 1 of section (iii) would normally be adopted.

Although not ideal, earthed metal capping complies with 522-06-06. Earthing the capping is pretty straight forward using a pop rivet and a short fly lead of cable with a ring crimp on one end

It's a bit confusing...should I be concerned that I haven't earthed the metal capping (which is within the zones)?
Too late now as I've filled the chases!