New to Forum with an Earthing Spike Question

[GHDirect]

Hi all, new to forum.
Need to install a "temporary supply" to assist my building plot.
I have supply pole on site which feeds existing property by overhead single phase 80 amp feed to wall mounted supply box. Existing property to be demolished so the local electric supply company are moving this box onto their pole in coming weeks and suggested I fit a similar box on other side of pole to hold my consumer unit and they will fly lead into it.
No problem except I need to put in an earthing spike. Not sure what size earth cable required from consumer unit to spike to meet regs. Can someone advise?

Regards
GHDirect

 

[telectrix]

chapter 54 bgb.

 

[Sintra]

Not so much the size of cable more important to get the size and the location of the earth electrode correct to obtain a decent Ra value.

 

[pencilpusher]

E54 will be along shortly!!

 

[Engineer54]

Just use 2 X 5/8'' extendable rods coupled together to give you depth and stability, and use a 10mm earthing conductor!!

When everything is completed and the DNO give you a new PME supply (assumed) to your property, you can use this now temporary earth electrode to connect onto the new MET as part of the Multiple Earthing arrangement!! So in essence, it won't be temporary, but a permanent earth electrode. It will need to have an Ra value of around
20 ohms or less for a meaningful connection to a PME supply though!!

 

[telectrix]

as sintra says. a 3ft rod is next to useless. use screwed rods at least 2. go for depth. 10mm cable should suffice unless part of the cable is buried and not protected., in which case go for 16mm. make sure RCD protection is fitted.

 

[D Skelton]

Tel beat me to it. Yes, it needs to be sized using an adiabatic equation with a min size of 4mm if not mechanically protected. This assumes also that your main earthing conductor is not buried at any point.

 

[glasgospark]

Hi all, new to forum.
Need to install a "temporary supply" to assist my building plot.
I have supply pole on site which feeds existing property by overhead single phase 80 amp feed to wall mounted supply box. Existing property to be demolished so the local electric supply company are moving this box onto their pole in coming weeks and suggested I fit a similar box on other side of pole to hold my consumer unit and they will fly lead into it.
No problem except I need to put in an earthing spike. Not sure what size earth cable required from consumer unit to spike to meet regs. Can someone advise?

Regards
GHDirect

Do you know how to conduct a earth electrode resistance test and have the appropriate meter , no point installing it if you can't test if its ok