Earthing

[Sparkii]

Hey guys,

I'm looking at a job just now and im a little unsure about the main bonding of incoming services. At the moment it's a large industrial unit and the plan is to make 11 smaller units that will be rented out. Each will have it's own 3ph board supplied by 40A isolator, gas meter and water meter. Do i need to bond the services in each unit from each DB, or would an earth from the main earth bar to the services as they enter the building be sufficient? All pipework in the building runs through each unit at high level and drops down to the individual meters

Thanks in advance

 

[Engineer54]

If these industrial units have it's own DB and are completely separated by the fabric of the building, then Yes, you will need to conduct a bonding exercise at each unit. The Units should be considered as you would in a block of flats, where exactly the same situation exists, with common service pipes branching and entering each dwelling....

If the building is a steel framed building, then you may use the steel frame of the building to bond out these services, and the Individual Unit DB's. But as the pipes enter the building, they will still need to be bonded by a copper conductor as well as the buildings structural steelwork to the main switchboards MET...

 

[Sparkii]

yep, all units separated by blockwork/plasterboard partitions. thanks for clearing that up