Online assistance for electrical trade people in New Zealand and Australia Login  |  Register  |   Forgot Password
Assistance for electrical trade people




Click here to send Ron a pdf document for publication on this Topic

Documents must be less than 200k in pdf format

Posted By Topic: Submain

Apr 11 2018 20:45

I’m replacing the main switchboard in a house tomorrow and I’ve noticed that the submain to the garage is a 4mm with 2.5mm PEC connected on both earth bars but the distribution board also has a electrode with 2.5mm MEC and MEN link connected. What’s the best option, keep the PEC and remove the electrode and MEN link or remove the PEC up size the distribution boards MEC to a 4mm? The garage is a seperate outbuilding.


Apr 11 2018 20:59

The outbuilding option with the remote earth electrode is the one to remove and revert back to a normal submain with active, neutral and earth conductors connected to the main switchboard and the distribution switchbosrd.

If you are repalceing the submain cable the building you are feeding is a garage, allow for the future and make allowance for an electric vehicle charging system. A electric vehicle can draw up to 32 amps for some charging modes typically found in domestic installations.

Apr 11 2018 21:04

Pluto good point about the car charger. This job I’m only replacing vir cable in the house. The submain is tps in conduit. With removing the electrode also the MEN link in distribution board will go? Does removal of a MEN link require an inspection?

Apr 11 2018 21:18

The removal of the remote MEN link; NO inspection is required when removing the link and reverting to a normal submain connections of A, N and E termnated at both ends.

BTW my inquiries in Energy Safety show the use of the outbuilding provision with a remote earth is NOT PEW needing independant inspection on initial installation.

Apr 12 2018 00:00

The words used in ESRs mean that installing an \"outbuilding\" earthing system is \"mains work\" and therefore high risk.
Perhaps not intended to be, but there\'s no getting away from the definitions - which ES wrote.