earthing

[andekoch]

Is it only me or do the rest of you also find that 80% plus of the places you do work on have no main earth from the CU to the distributors terminations.

It also amazes me that the distributor cant tell you what type of system they have at the property. Sometimes the type is obvious especially if TNCS or TNC but not so easy to spot if TNS or a very old installation. What advise in these cases?

 

[electricAl]

Sometimes the type is obvious especially if TNCS or TNC but not so easy to spot if TNS or a very old installation. What advise in these cases?

TNC

Do you really mean TNC?

As for TNS or TN-C-S, your meter will tell you. Unless you`re unlucky enough to have a cable-sheath with a clean enough earth to match your Zln reading, a simple Ze will usually split em.

If it`s still inconclusive (its mostly definitive) do a N to E loop - if PME it`ll be tiny due to the PE/N link at service head

As for such a high % of unearthed installs, no i don`t relate to that atall. It happens yes, but not that often.

 

[andekoch]

Thanks ElectricAl. TNC was a typo, too late and too many letters. What you suggested is what I do to find out the difference, was just wanting to see if anyone had any other good ideas.
Guess I have just been unlucky with the places I have been called into re the earthing. It does seem high to me as well hence the question.

 

[electricAl]

Thanks ElectricAl. TNC was a typo, too late and too many letters.

Ever thought about opening em in the morning instead?

Anyway, glad to have helped (if i actually did )