Would these count as extraneous conductive parts???

[oharaf]

Currently carrying out some minor changes and up grading a CU for a Landlord.

The CU is located in the very substantial cellars of a property, these cellars used to be air-raid shelters during the war.

As a result of their previous use the pillars that the ground floor sits on were strapped in heavy steel / iron which is now more rust than anything.

There are a few steel / iron lintels as well, the floor above has been replaced, not that that has any bearing on the issue.

Now my gut feeling is that I need to link all these parts together with bonding and terminate into the MET block.

Anyone got some views on this? I feel I am correct but I don't want to do anything not required.

 

[captaincargo]

If the steel pillars are part of the foundations then quite a large area of them will be buried under the house therefor, my view is they can introduce an earth potential so must be bonded.

If like you state,the pillars are just wrapped in this steel then no they do not need be bonded.

 

[Spark123]

One way to tell if it is extraneous is to conduct a measurement between the said item and the MET. If the resistance is below 22KΩ then it can be considered to be extraneous hence needs to be bonded.
If it is above 22KΩ then it doesn't need bonding.

 

[oharaf]

Top hole 123 that will do it for me.

 

[Taylortwocities]

I'm not sure how you'll clamp your bonding onto a large rusty pole though...

 

[flyingsparks]

I'm not sure how you'll clamp your bonding onto a large rusty pole though...

Cant beat crimp eyes, and a tec screw for bonding steels, with a warning tag from a ec clamp under it..

 

[RF Lighting]

I normally use a CT crimp, and tap a thread into the steel beam

 

[oharaf]

Yes alot of rust however, a good scrubbing with a grinder will reveal some shiny steel hopefully, drill a hole and crimp, nut n bolt and a tag should do it

These steels definitely go into the ground, 2 sections of them covering a distance of 30m!!!!!!

My good that will be some bonding.

Will be taking the camera with me, there are some beautiful sights to behold.

The top floor is served by a 20A radial!!!!! Well it was supposed to be but somehow someone has managed to cut right through the cable that ran vertically up through 2 floors 110cm from the wall without an accessory in sight!!!!

Needless to say we have had to turn this into a ring final!!!!!!

The CU is 'fixed' onto some old skirting board that the wood worm have been munching for years

The DNO board is 10mm chip board that has soaked up years of damp and when I went to upgrade the bonding it crumbled ALOT so a nice job for them