main bonds.

[ianmacd]

When installing main earth bonds, is it acceptable to have them terminate in the meter cupboard in an earth block, which has a 16mm tail going into the CU and another 16mm tail going into the PME connection block? Or should the 10mm go all the way into the CU?

Your main bonds need to go back to the MET. That can be inside the CU or external to it. The MET is the first block after the Earthing method (so if you have a TN-C-S supply with connecing to an Earth Block and then onto a CU then the Earth Block is your MET.

 

[AAAMUSEMENTS]

Is there a specific type of clamp available for the smaller pipes used for oil? I have used a standard Tenby on my oil pipe and it looks as though it will be impossible to route the 10mm earth cable through the cable clamp the angle it sits at means there just won't be a gap... will see if I can upload a photo.

Edit added pic. Lighting is not very good but that lower metal plate in the foreground needs to be used to clamp the cable between it and the upper plate, but there is no room at the back of them as the plate is tight up against the pipe.

Also if I were to tighten that right hand set screw, it would cut right into the oil pipe...

Just as an update, and for information, standard Tenby style clamps are unsuitable for use on small bore oil pipe.

The diameter is not sufficiently large to clamp the end of the strap between the fitting and the pipe, and thus the fitting is easily overtightened leading to serious deformation and squashing of the pipe, and an insecure earth fitting.

I now have a section of oil pipe that will have to be replaced. but at least I can use the opportunity to put in a section of 15mm!

headbang