Main Earth Connection

[MvP Electrics]

hi all,a friend of mine sent me this pic today. it looks like a ec14 or ec15 earth clamp to me. i was taught never to use this as a connection to armoured. am i correct or is this ok?

thanks


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[xraytek]

If I remember correctly this book lists it as wrong and gives a regulation number that the issue fails to comply with, although the reg number is quite a general statement.

The main problem being that this type of clamp can squash and damage the insulation of the live conductors if too tight.

 

[Spudnik]

I come across this nearly all the time with TNS.

Contact the DNO and ask for a proper connection.

 

[slocm3105]

I find it hard to tell the difference between a normal clamp and spring loaded clamp without really looking close. Ive rung the DNO many times about this and they say that they always fit spring loaded ones now though for the reasons already mentioned above^^.

 

[claire_r]

90% of tns supplies I go to are earthed using this bs951 clamp. It doesn't comply but there is nothing you can do about it except note it down as the dno aren't interested

 

[Ridgey88]

if the TNS supply has the old blck earthing conductor connecting to the MET looks like 4mm2 can we connect to that clamp with a new bit of 16mm2 or is this down to the DNO? im on about the original clamps with the soldered connection.

the reason i ask is because i did a board change and it had the old black 4mm2 and i crimped a lug ont the 16mm2 and connected it to the clamp on the tns earth sheath in addition to the existing earthing conductor. hope this makes sense!

 

[slocm3105]

if the TNS supply has the old blck earthing conductor connecting to the MET looks like 4mm2 can we connect to that clamp with a new bit of 16mm2 or is this down to the DNO? im on about the original clamps with the soldered connection.

the reason i ask is because i did a board change and it had the old black 4mm2 and i crimped a lug ont the 16mm2 and connected it to the clamp on the tns earth sheath in addition to the existing earthing conductor. hope this makes sense!

I'd just put an MET there with the existing 4mm from the lead sheath going into it. Then whack ur 16mm from ur consumer unit into that MET. Dont touch their stuff I say .

 

[Spudnik]

I'd just put an MET there with the existing 4mm from the lead sheath going into it. Then whack ur 16mm from ur consumer unit into that MET. Dont touch their stuff I say .

I very much agree, although i am guilty of running a new 16 to the sheath clamp.

NOT recommended, as there is a very high risk of over tightening the clamp and...............

 

[MvP Electrics]

thanks for all the replies. went to the job to help my friend out. called edf on behalf of the client they told me 10weeks for a cut out and change of the main earth. be a good xmas present for the client i suppose.

 

[Ridgey88]

I was going to use this as one of my examples for my niceic assessment next week, should I remove this then? It is secure looks very good but if your not meant to touch there stuff then I suppose I shouldn't of done it! Just wondering if the nic man will have a problem with it as that's the last thing I want!

Cheers

 

[pevvers]

I would say he will have a problem with it if you admit to doing it!