UK Black cable off supplier's incoming cable?

[impish15]

Hi,

Any suggestions what this black cable is coming off the supply's incoming cable? Its a TN-S system, I thought it could be the earth conductor but the cable is black not green/yellow, plus it looks much smaller than 10mm2 plus there is already an earthing conductor coming off the sheath going to the MET.

Any advice welcome
Dennis

 

[mainline]

I've never had an issue with it outside. And it's been used by thousands of satellite and aerial installers over the years.

There must be different types, the stuff I have used has crumbled.

I just did a quick search on the internet and found some say its ok and some say to cover it in pvc tape.

Self Amalgamating Tape 25mm x 10m - The DX Shop Limited

Self Amalgamating Tape 25mm width x 10m reel Perfect for weatherproofing cable connections.

thedxshop.com

There are different types one being rubber and one being PIB whatever that is.


Self Amalgamating tape is typically made from EPR rubber, EPDM rubber, butyl rubber or PIB (polyisobutylene)

Like this stuff isn't UV resistant

Self-amalgamating Tapes – Low Voltage Rubber Tape HTAPE-POWER600 19x6.7 (711-00200)

711-00200

www.hellermanntyton.co.uk

 

[DPG]

There must be different types, the stuff I have used has crumbled.

I just did a quick search on the internet and found some say its ok and some say to cover it in pvc tape.

Self Amalgamating Tape 25mm x 10m - The DX Shop Limited

Self Amalgamating Tape 25mm width x 10m reel Perfect for weatherproofing cable connections.

thedxshop.com

Must have been cheap stuff.

Never heard of covering it with pvc tape. The rubber layer formed should be sufficient.

 

[impish15]

Just did a Ze test with the newly installed earthing conductor and got 0 ohms!!!!!!!!

 

[mainline]

Just did a Ze test with the newly installed earthing conductor and got 0 ohms!!!!!!!!

Did you try nulling the leads

 

[impish15]

Did you try nulling the leads

Yes leads all nulled before testing

 

[mainline]

Yes leads all nulled before testing

Have you another mft to try or another set of leads

 

[impish15]

Have you another mft to try or another set of leads

Good shout. I’ll grab one from the other electrician I work with and test on Monday

 

[Jim_e_Jib]

I will have to tell the amalgamating tape around the junction box to the alarm cable in my field to the barn that it should not have lasted twenty years, naught tape.

You have a field and a barn? You kept that quiet.

What ever next - a former owner of property in mainland Europe?

 

[mainline]

Must have been cheap stuff.

This is the stuff that I've been using, I bought a dose of them a few years ago, I see that it was discontinued in 2019.

 

[mainline]

Good shout. I’ll grab one from the other electrician I work with and test on Monday

I wonder if you are using fluke, as there was something about double nulling causing problems.
Let us know how you got on.

 

[impish15]

I wonder if you are using fluke, as there was something about double nulling causing problems.
Let us know how you got on.

Interesting didn’t know about the double nulling issue. Yes using a fluke 1653. I’ll keep you updated next week once re-test done

 

[telectrix]

This is the stuff that I've been using, I bought a dose of them a few years ago, I see that it was discontinued in 2019.

been searching for S/A tape in Green/Yellow. can't find any anywhere.

 

[mainline]

Interesting didn’t know about the double nulling issue. Yes using a fluke 1653. I’ll keep you updated next week once re-test done

Do you have any news ?

 

[impish15]

Do you have any news ?

Hi apologies for the delay, I have only got around to re-doing the test yesterday as caught up between jobs. I used my colleague’s tester and got 0.10 then I re-tried my Fluke considering the possible double nulling when I did the test previously and got 0.11 so looks like I might have double nulled when I did the test before. Thanks for the heads up on that

 

[davesparks]

I asked him at the time and he said it was electrical tape. Assuming he should have used self amalgamating tape?

It doesn't matter, it doesn't need any tape at all.
The lead sheath is fine to be left exposed, the extra layers on top were there for extra protection underground or in harsh environments.