Grounding a Wall Mounted Data Cabinet

[Jin]

I have recently taken over in the IT side of a medium company and one of the things I have noticed is a terribly installed wall mounted Data cabinet.

I have spent the weekend sorting it all out so it all comes up to spec but wanted to clarify on some points.

It is currently mounted on the wall but has not been earthed.
Power is ran from a 13amp BS 1363 from the trunking below to a small UPS in the cab. The UPS then breaks out onto a BS1363 PDU within the cab which is for a number of smaller DC powered devices (12, 24 and 48v transformers).

There is also a number of network switches installed (max, 250W), this is all grounded to an earth bonding bar that I have installed into the rack.

My question is, what do I earth the bonding bar to? Would it be acceptable to earth it to the earth in the ring main running below the wall mounted cabinet?

 

[Pete999]

Does the flex feeding the cabinet not have a cpc

 

[Jin]

Does the flex feeding the cabinet not have a cpc

It does but some of the equipment that the UPS powers does not and this equipment is then has presentation elsewhere such as the router which is DC voltage but also connects to POTS or the CCTV.

Maybe I am being overcautious but I have always thought that metal data cabinets should always be earthed. Certainly seems to be the case for Data racks.

 

[Ian1981]

I can only comment from experience but whenever asked to install data cables and power for a cabinet it is requested by the data company that a 10mm bonding connection is made to the cabinet back to the consumer unit.

 

[MisterE]

Whenever we installed wall mounted data cabinets we requested (from the electrical contractor) a dedicated spur to a twin 13 amp socket mounted above or to the side of the cabinet position with a 6mm bonding cable from the nearest board. (We'd indicate the required position by the use of a sticker when surveying the site taking into account the cabinet size, ceiling height, furniture and the route of the data cabling trunking etc.)
Then when the data cabinet was installed the 6mm cable would be bonded to the cabinet earth stud, not forgetting the cabinet manufacturer's bonding kit for the door and any detachable side panels.