Earth rod

[Carlosfandango]

This might sound like a daft question to some of you guys. I've never had to work with TT systems before and I'm wondering how you go about getting a spike into rocky ground? The job I've been to look at has a spike in just now but the Ze at the mains is 107 ohms. I need to get this to an acceptable reading. I'm led to believe the area is build on bedrock! Any advice?

 

[shanky887614]

Here you go Shanky from BS 7430 section 10.2 ....

A number of rods or pipes may be connected in parallel and the resistance is then practicallyproportional to the reciprocal of the number employed so long as each is situated outside theresistance area of any other. In practice this is often assumed to be satisfied by a mutual separation equal to the driven depth. Little is to be gained by separation beyond twice the driven depth.
So 1.8 it is then.​

Sometimes I think im psychic with the amount of bs that comes out of my mouth that is actually useful.

got told by an engineer at schneider that lad is too clever lol.

 

[GLENNSPARK]

My test gear is one of the first things that gets packed!

well..
if thats your comfort blanket...

everyone needs to feel wanted Archy....