Temp supply and earthing

[sr771]

Hi, after your invaluable experience on this please, doing a refurb of a smalll office block and am putting in some temp supplies to 110 tranny and tea room. Power currently off as building unused for some time, but dno, prob edf!!, coming out to reconnect and then later move cut out. Have heard from other sparks they may want earth rod for the temp supply, what are your experiences. The surrounding area is car park and the building has a basement so putting in a rod may prove difficult. Thanks for your time

 

[volt-dropping]

I was told at 17th edition course by select lecturer that a main bond onto any main steel h-beam or girder sunk into foundations was a good way to overcome sub-standard electrode results meaning even with an earth spike the earth was insufficient after the associated tests were carried out.

If the building has an h-beam girder frame i think this may be an acceptable method but i would check with your local electrical regulatory authority .

 

[bugsy]

If its an existing building with an existing cutout and switchgear the DNO will just reconnect the supply ,
however if your doing a stripout I disconnect and stripout all redundant cabling , then supply your kit via RCBO'S

 

[Sintra]

If you ask for a temp supply then the DNO will make you install an electrode.

Earth Electrodes

All of the following can be used as earth electrodes :

Earth rods or pipes

Earth tapes or wires

Earth platesUnderground structural metalwork embedded in foundations

Welded metal reinforcement of concrete embedded in the Earth (excluding pre stressed concrete)

Lead sheaths & metal cable coverings provided the following conditions are met :
a - the cable covering must be in effective contact with Earth
b - the permission of the cable owner must be obtained
c - the owner of the cable must be able to inform the owner of the installation of any changes to the cable which may affect it suitability as an earth electrode 542.2.1, 542.2.5,


A metal gas or water pipe must not be used as an earth electrode. 542.2.4

 

[chris gray]

only ever once had dno give us a temp supply.
they stated they wanted an electrode in at the end of a minimum 9meter of cable?
didnt get where they got that figure from tbh?