TN-C-S with Ze higher than 0.35 ohms

[markusjames]

Hello!

Where do I start to troubleshooting with issue of higher reading of Ze 0.45ohms with TN-C-S earthing arrangement. Thank you!

 

[Midwest]

Is it an issue for your Zs readings? You could ask your DNO, but I think they might say in was within acceptable limits, unless there's something nasty looking in the earthing facility.

 

[markusjames]

Is it an issue for your Zs readings? You could ask your DNO, but I think they might say in was within acceptable limits, unless there's something nasty looking in the earthing facility.

I will check with our DNO. Thank you.

 

[radiohead]

Worth carrying out a test L-N and seeing if the reading is the same. Some service heads have a link fitted between the earth block and N block. On two occasions I have recorded a high Zs reading but the L-N reading was much lower. Turns out the link was missing and the high reading was via the only earth path through main bonding.

 

[markusjames]

Worth carrying out a test L-N and seeing if the reading is the same. Some service heads have a link fitted between the earth block and N block. On two occasions I have recorded a high Zs reading but the L-N reading was much lower. Turns out the link was missing and the high reading was via the only earth path through main bonding.

Thank you! I will try this test.