TNS Earth clamp bust ?..

[liddley]

Hi Guys, Just a quick question regarding the earth clamp on a Domestic TNS system. The property we are rewiring at the moment has a TNS supply and the earthing clamp on the paper lead supply cable has rotted and is unusable. I spoke to DNO (Northern power grid) and asked if they could renew it for us. The call centre said no do it yourself or pay £160+ to have it converted to PME. I thought that if their equipment was faulty they were responsible for it and had to fix it. I know some sparks just stick a pipe bonding clamp round the cable and use that? I don't fancy doing anything with the cable because it looks knackered. Is a bonding clamp acceptable as long as Ze is correct?

 

[Marvo]

They're probably just taking a chance. I'd just tell them it's their equipment so fix it! I'd also decline point blank to attempt any repairs on a cable of that age.

 

[Zebra Stripe]

And make some sandwiches, a flask of tea and prepare for an extremely frustrateing day
oh heck..I cant spell

 

[telectrix]

i can't dance, but am i bothered,,,, am i bollox.

 

[R G]

The clamp required is a phosphor Bronze clamp , suitable for use on the lead sheath without the electrloytic reaction , I used to have loads on the van , The ruling regarding this is if the DNO supply the earth connection it is then their responsibility to maintain it ..

 

[Zebra Stripe]

Its a bit of a grey area.....they will/may say there resposibility ends at the sheath...yours is the earthing conductor and its connection to the sheath.....however, there's not a chance I would put my life at stake to connect to the cable sheath mentioned in the OP

 

[R G]

Old mates of mine I had worked with for years on the DNO (Jointers)mostly do service alterations but have a massive back log on earth upgrades , Probably thats why they would like you to do it , Tell them its leaving the installation un safe , its their responsibility

 

[Marvo]

If the clamp is broken is there an earth on the installation at present.....

 

[telectrix]

only through the gas and water. dangerous situation. DNO emergency number. what's the standing charge on the bill for?

 

[liddley]

No earth at moment, but system not in use and isolated, all old stripped out and ready for new install. The scabby old earth cable looks like it rotted off ages ago very small csa looks 4mm ish.

 

[Engineer54]

Contact the DNO Area Engineer and explain the situation, reminding him that they have a duty of care to maintain their equipment to a recognised safe standard!!

Not that i'd ever recommend doing so, especially if you feel that you are not confident in doing so... But if you were to replace the earth clamp yourself, then you're only real option is to use a constant pressure spring clamp, that will not cause any detrimental affect to PILC cable. Hepworth earthing clamps require a special tool that is doubtful you'd ever use again...

 

[GLENNSPARK]

No earth at moment, but system not in use and isolated, all old stripped out and ready for new install. The scabby old earth cable looks like it rotted off ages ago very small csa looks 4mm ish.

well...you do right getting the DNO to come out early and sort their equipment (including earthing arrangements) first...as it can take them upto 6 weeks to turn up...

 

[GLENNSPARK]

this is the reason why a Ze should always be carried out at survay stage....

a very good example of why here...

 

[Engineer54]

Its a bit of a grey area.....they will/may say there resposibility ends at the sheath...yours is the earthing conductor and its connection to the sheath.

Not so, ...If it's a DNO supplied earthing point, then they have a duty to maintain that earthing point. If that means converting to a PME connection from a TN-S connection, then so be it, they have maintained th provided earthing point, and fulfilled their duty of care!!

 

[liddley]

If I wanted to go ahead a pay for PME ,Northern Power Grid quoted up to 10 weeks for works to be carried out.God knows what time they will quote for a free repair of there equipment . We will see tomorrow when I phone them again.

 

[Engineer54]

If I wanted to go ahead a pay for PME ,Northern Power Grid quoted up to 10 weeks for works to be carried out.God knows what time they will quote for a free repair of there equipment . We will see tomorrow when I phone them again.

Why would you pay, it's their problem not yours, or your clients!! Just insist on talking to the Area Engineer. Don't whatever you do, waste your time talking to the office telephone girl!!