[Question] Good Morning

[Dennis28]

we were asked to do COC for an installation built 1960s so there is no earth conductors only the steel conduit that serves as earthing system.
now we know SANS 10142-1 - steel conduit cannot be used as earth conductor although it must be earthed.
the conduit we tested, tested good wrt continuity and is overall in good condition.
i know there was a clause that stated if the installation is stock standard with no changes and was done prior 1995 it can be passed as safe to use.

i have been reading through the updated SANS 10142-1, DON'T KNOW IF IM JUST MISSING IT.
i need some help here please, can a COC be issued if earth wire isn't installed for this installation.
can the metal parts in PSO and light boxes be earthed from metal box with earth wire and obviously a sound connection using lugs and bolts or pop rivets.

it must be noted that i haven't been active with installation work and are getting back into things.

[Derlyn]

If the installation is stock standard as you have mentioned, then the socket outlets will have metal bases and if your earth loop tests are satisfactory then it's considered reasonably safe and no extra earth wire is required, however, when a plastic socket outlet is fitted then you have a problem. An earth wire will then have to be pulled in between the consumer earthing terminal in the DB and the socker outlet.

It is then also advisable as per the note on page 158 to fit an earth leakage relay if there isn't already one, irrespective of the date of the original installation.

The above is how I would handle it. Let's hear what the other toppies say.

[Dennis28]

Hi Derlyn

If the installation is stock standard as you have mentioned, then the socket outlets will have metal bases and if your earth loop tests are satisfactory then it's considered reasonably safe and no extra earth wire is required, however, when a plastic socket outlet is fitted then you have a problem. An earth wire will then have to be pulled in between the consumer earthing terminal in the DB and the socker outlet.

It is then also advisable as per the note on page 158 to fit an earth leakage relay if there isn't already one, irrespective of the date of the original installation.

The above is how I would handle it. Let's hear what the other toppies say.

Thank you so much for the reply and advice, i appreciate it.
the battle on this side is also how some inspectors read SANS10142 -1.
Sorry to say. their opinion of how they read it is final and i don't want problems after the fact