TN-S Code Two??

[gap30]

Was talking to a friend earlier about the number of installs i have been to recently with no main earth, he told me that the NICEIC are now saying any TN-S with no soldered connection (earth clamp on metal sheath etc) should be made into a TT and Code 2 it, bear in mind this is for a large social housing company. I recently discussed this myself on my 12 month NICEIC renewal and was told roughly the same thing. Anyway i have reported this several times to Scottish Power on some consumer unit upgrades, when i have spoken to guys from Scottish Power about this they are happy with an earth clamp in most cases.

My friend reckons the NICEIC are soon going to insist on this.

I always thought another way around this was to use a Hepworth clamp (have never done so myself tbh)

Thoughts anyone?

 

[Knobhead]

Thats a new one on me.

Great how mis-information gets about.

 

[Engineer54]

I would hazard a guess that most of the DNO's underground distribution network cables are still based on the PILC cables installed donkey's years ago, which gave sterling service for 60, 70, 80 years, to virtually the whole countries distribution networks at HV/MV/LV. Many still giving sub 0.20 Ze values on the LV too!! OK, many are now, or being converted to PME, due to corrosion in sections of these cables, but most are still in service, and probably will be for a good many years to come!!

 

[Knobhead]

A few years back I diverted a PILCSWA that had been installed in the 1930’s. When I made it off again it was in perfect condition inside the hessian outer serving. OK it’s a messy job cleaning the armours and lead but the tar preserves them perfectly. Never want to make of a DWA again though, they are a pig to make look good on the wiping cone. We still had some tape armoured, I managed to avoid them.

 

[Engineer54]

It'd be wrong for me to ignore your statement that you have witnessed the DNO fitting a clamp,I've no reason to doubt your integrity. But I can say I have never seen it personally,and dont expect to!

Just a little more information on the DNO's still using 951 clamps, from the commercial/industrial section of the forum.

They just cut back the armouring and bonded the clamp to the lead outer sheathing and applied a resin to the exposed area.

From what I saw it was just a 951 clamp and a tar like resin from a mix. I will take a picture tomorrow and post.

We'll know for sure it seems, tomorrow with a photo!!

 

[Engineer54]

Never want to make of a DWA again though, they are a pig to make look good on the wiping cone. We still had some tape armoured, I managed to avoid them.

They are a pig to make off into a gland too, even the single wrap armoured cables are!! Far easier to terminate them onto a top hat gland (similar to the photo above but not coned) or cone gland, with a nice heat shrink adhesive tube covering!! lol!!

 

[Knobhead]

Davis of Derby used to make a stalk gland for normal DWA I enjoyed working with them. It was just the PILCDWA I hated.

For PILCSWA CMP made a lead lined gland. They were a doddle to use.

 

[Engineer54]

Ah, ...never actually worked with PILC STA only the PVC stuff, with which i think was BICC brass glands, (similar build to a standard SWA gland, but for steel tape) and certainly not easy to make off trying to keep the wrap tight while securing to gland.
The one thing i remember vividly though was how easy it was to slice your hands to ribbons with that steel tape!! lol!! They made a gland for the DWA too, but only ever got to watch that termination being made off, ...that and listening to lot's of swearing and seeing things being thrown all over the place!! lol!!

 

[Knobhead]

Ah, ...never actually worked with PILC STA only the PVC stuff, with which i think was BICC brass glands, (similar build to a standard SWA gland, but for steel tape) tap) and certainly not easy to make off trying to keep the wrap tight while securing to gland.
The one thing i remember vividly though was how easy it was to slice your hands to ribbons with that steel tape!! lol!! They made a gland for the DWA too, but only ever got to watch that termination being made off, ...that and listening to lot's of swearing and seeing things being thrown all over the place!! lol!!

You been spying on me?

I'd like to hear the arguments about using the armours as the CPC.

 

[Engineer54]

You been spying on me?

I'd like to hear the arguments about using the armours as the CPC.

You'll get no detrimental arguments from me!! lol!!

 

[telectrix]

nor me. as i've not worked with the stuff.

 

[Engineer54]

Tony, ...Are you asking for arguments about the lead sheathing of PILC, or armouring as a whole on SWA and STA cables etc??

 

[Knobhead]

DWA. I've no qualms about the integrity of a lead sheath.

 

[Engineer54]

DWA. I've no qualms about the integrity of a lead sheath.

So what would be your thoughts on using the DWA as the CPC?? You sound a bit doubtful?? lol!!