Discuss Commercial premesis in the Commercial Electrical Advice area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

sparks1234

-
Arms
Reaction score
85
In a commercial building that is owned by a landlord and then each office area has its own water supply and distribution board.
The sub-main comes from a panel from the main installation in the basement so the sub-main is a TN-S but main incomer is usually a TNCS.
When form filling you are asked what type of supply at the origin, I take it this means the main incomer where it enters the building, when asked for the Ze, what do you put in? is it a limitation as you cant turn the supply off to disconnect the earth.
As for the bonding, are they enquiring as to the bonding for the main building or your particular zone?
 
Hi.

When it isn't possible to measure Ze and PFC, then you are permitted to use the value obtained from the DNO by enquiry. For a TN-C-S they'll just tell youit should be less than 0.35 and tell you to calculate PFC from that.

Is there a main water incommer in the basement where the supply is branched off to each unit??? If so then the water should be bonded here back to the MET at the main intake and, point of entry to each unit.
 
Hi.

When it isn't possible to measure Ze and PFC, then you are permitted to use the value obtained from the DNO by enquiry. For a TN-C-S they'll just tell youit should be less than 0.35 and tell you to calculate PFC from that.

Is there a main water incommer in the basement where the supply is branched off to each unit??? If so then the water should be bonded here back to the MET at the main intake and, point of entry to each unit.

The water comes into the building and rises up through the risers and spurs off to each office. So I am assuming that you would need to be satisfied that bonds are in place in the basement and at entry to the office to satisfy the cert. Assuming that the pipe to the office is copper not plastic
 

Reply to Commercial premesis in the Commercial Electrical Advice area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock