Ze Reading query

[malcolmsanford]

Your quite correct only the Ze can be taken at the origin, You can though at a sub main take a Zdb and this is normally done with bonding and earthing connected. Then on the Schedule of Results you note it on the deviation section at the bottom.

This is allowed because in many circumstances espicially in commercial/industrial it is virtually impossible to disconnect the main earth conductor at the origin to do the Ze, and therefore impossible to do any work on any part of the installation.

The test is carried out and the value recorded. If there is any difference between the recorded value of Ze and the recorded value Zdb then this difference is the value of the parallel paths associated with the earthing and bonding conductors and this value must then be added to all subsequent measured values of Zs.

 

[telectrix]

Think this is getting a bit too involved. Installation is established, up and running. I read Zdb just to establish that there was an acceptable earth in place before energising my new circuit. Tomorrow, hopefully, they will have finished potato picking and storing and then I can finish installing the lighting, roller shutter door supply and complete testing, including measuring or enquiring the value of Ze . The main reason thet the ring main I had installed had to be up and running was to provide a supply for power tools, mine and the door installer's.

 

[Jimmy Boy]

I see Malcolm thanks for clarifying that's really good info I didn't realise Zdb could used for a new installations as there isn't a box for it on a EIC, thought it was more for a PIR good info tho.

telextric I wasn't having a pop at you BTW I am not like that I am just deeply interested in different methods people use for installs if I am learning it's all good.
ATB S

 

[telectrix]

didn't think you were, was just trying to make my point with as few words as poss. for a sunday when we should all be having a lie-in, waiting for her indoors to do full english in bed, lol