which code

[stevep23]

Hi Folks
First a bit about me. I work as a multi skilled technician with a electrical bias for a large company in the north west, with redundancy looming I decided to concentrate on the electrical side of my training back in 2008 and successfully completed 2391, with a view to going it alone. At the last minute I had the rug pulled from under me and couldn’t go with the redundancy payment which would of helped to get things going, it didn’t seem to be a good thing at the time but I realise I probably had a lucky escape seeing how some of you guys have had a tough time in past few years. Hope things pick up soon.
I have carried out a periodic inspection for a friend who is having a really hard time at the moment with serious illness in the family and youngsters to look after. My question is about which code for a DB in his garage with the 6mm T&E supply from the main consumer unit in the house. The cable is in plastic trunking for the first 2 meters up the wall on the outside of the house and from then on clipped direct until it reaches the garage. There is a water point below the garage DB and the supply characteristics for house is TN-C-S. I have read a lot on the site about exporting/ not exporting PME but could do with some help.

 

[telectrix]

how is the 6mm protected at the CU? is it from a MCB or henley blocked?

 

[jaresquire]

Is the water point metallic or non-conducting?

 

[stevep23]

The 6mm is in the trunking before passing through the wall and cavity into the CU and a 32A MCB

 

[stevep23]

The water point is 15mm copper pipe

 

[telectrix]

the cpc in that 6mm T/E is only 2.5mm, not sufficient csa to bond the water pipe in the garage back to the MET. either run a separate 10mm from MET to garage water, or make the garage TT. ( all circuits in the garage would require a 30mA RCD ).

 

[stevep23]

Thanks telectrix I have suggested making garage TT but because of time [FONT=&quot] constaints etc the work could not be carried out so need to enter this on the certificate would you enter this as a code 1?
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[telectrix]

code 2 IMO. it's not an immediate danger. i would, however , fix a bond to the water, assuming it's an extraneous conductive part.

 

[stevep23]

Thanks again telectrix water does have bond and cu's main isolation is via 30mA RCD

 

[telectrix]

might only warrant a code 4 then. if it complied with the regs. at the time of installation.

 

[Bul]

Telectrix
Can you explain a bit about "or make the garage TT". It's just that I have never heard of a sub circuit(?) this way. How would this be done in practice?

 

[telectrix]

you disconnect the cpc of the feed cable at the load end, then whack a rod in to earth the garage installation.

 

[opsman]

T&E cable shouldn't be clipped direct outside. It isn't suitable for the solar radiation it will be subjected to and will degrade over time. It should have some form of mechanical protection i.e conduit or trunking. This constitutes a code 2 departure.

 

[Farmelectrics]

how many rods would you put in telectrix would you be ghappy with one

 

[D80]

T&E cable shouldn't be clipped direct outside. It isn't suitable for the solar radiation it will be subjected to and will degrade over time. It should have some form of mechanical protection i.e conduit or trunking. This constitutes a code 2 departure.

It may be just that we don't get a lot of sun in Northern Ireland, but I've seen T&E clipped direct outside showing no signs of problems after almost 30 years...