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Posted By Topic: Conductor replace.

May 21 2017 21:13

Hi guys,
apologies if this has been covered in detail - I had a look for it...
Looking at replacement of metal conduit wiring to a couple of outlets in an old house.

So conductor gets replaced - maintenance.
SERF gets replaced with MCB - maintenance.

But, currently no earth bar - we're looking at one of those earth bolts with myriad earths connected, then linked into the Main Neutral lug.

So, the question is whether my replacement circuits can have their earths connected in the same fashion, or whether a new earth bar needs to be installed to facilitate these terminations, and linked to the existing earth bolt.

I'd rather not, as it is an old asbestos board that would need to be drilled.
Appreciate your thoughts on this.
- Braden

May 22 2017 08:34

Fig 5.3 covers the wide variety of ways in which PECs may be terminated, each referenced back to the relevant sub-clause. There is NO requirement to have an earth busbar.

On the other hand, there is a requirement for each outgoing final subcircuit to have its N terminated on a separate terminal - but that would apply to a new subcircuit, and what you propose isn't a new subcircuit. ESR 59 (3) covers how existing installations may be maintained, and item (b) would allow your replacement cable to be terminated in the same way as the conductors being removed.

May 26 2017 07:31

Hi Alex, thanks.
So you're saying an earth bar is not even mandatory on a modern install, and that a common bolt is acceptable by today's standards?
(Not that I would connect in such a fashion)
- Cheers