# Extension Leads in commercial offices



## frank (Feb 6, 2007)

Trickster.

IT- equipment must be directly connected to a socket outlet or at the least not more than one in line extension. There are problems connected with earth/grounding of IT equipment hence the rule. Think of the common bond earth arrangement in earth dual sockets for IT ( I am assuming by the way you are in the UK) 
The health and safety /fire issues you raise are fundamental but mention the residual fault currents that circulate in these circuits and the effect these will have on the correct operation of logic circuits.

Frank


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## trickster77 (Apr 28, 2007)

Thankyou frank, great help. Would you happen to know whether this is covered in bs7671, the electricity at work act or health and safety law


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## frank (Feb 6, 2007)

Covered in BS7671 but can't locate it for you just now.


Frank


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## Minky (Dec 30, 2007)

*High Intergrity Earthing*

I had a similar problem,best solution was to allow one trailing gang if really necessary,but not preferred method.
If possible install extra socket outlets,but be sure that the earth conductors are seperate at each outlet,that is if the circuit is wired as a ring,then ensure one conductor to one terminal,and seperate terminals at the DB.Only L and N conductors are wired into the same terminals.Also for best results connect the earth bar to a seperate earth electrode if possible,this will ensure a 'clean' earth or at least will give you a fairly low impedance path to earth to carry the earth leakage current generated by appliances connected to the circuit.Not a good idea to put IT equipment on an RCD also,so if possible you may wish to fit switched fused outlets to each piece of equipment,this also makes it harder for the opportunist thief to take that expensive new TFT monitor!!.


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