high Zs readings

[Dave the spark]

Did an EICR in a domestic property, earthing arrangement was a TN-S with a Ze of 0.51 ohms.

There are 2 ring final circuits protected by 32amp 60898 type B mcbs. Both circuits have additional protection from a 30mA RCD.

My Zs readings for the circuits are 1.63 ohms and 1.89 ohms.

My question is, with the additional protection of the RCD would it be acceptable to leave it as is and make a note of the situation? Or can I contact the DNO to ask them to improve the external earth? Other than that I'm not really sure what I can do.

Looking for some advice, rather than snide remarks.

Thanks.

 

[Jay Sparks]

When doing the Zs test on "no trip", it does it at around 17mA and takes longer and gives a higher reading. But on "Hi" current, it's around 25A and it does it quite quickly but can give a lower, more accurate reading. Obviously these will vary on different meters. But to get a more accurate reading you need to bypass the rcd.

Jay

I need to proof read before submitting.lol some bad spelling in there.......now corrected in the quote.

Jay

 

[Dave the spark]

I need to proof read before submitting.lol some bad spelling in there.......now corrected in the quote.

Jay

I got the gist of it anyway, thanks