Just when you thought nothing else could create confusion, well add an earth spike to the mix. Imagine that neutral bar earthing again
Take note of the earth wire to the electrode (spike as we call it) it must be at least equivalent to the phase conductor. If you have a 16 mm phase wire in an 8 KVA or bigger, then a 16 mm earth wire is required.
If a 5 KVA is installed and you decide to use 4 mm phase conductors, then a 6 mm earth wire to the electrode is still required.
The question, when is an earth electrode required? Do you just knock an electrode into the ground and connect it to the main earth, the standby unit and the solar panel rails?
7.12.3.1 Neutral bar earthing
7.12.3.1.1 Protection in accordance with the requirements of 6.7 shall be
provided for the electrical installation in such a manner as to ensure correct
operation of the protection devices, irrespective of the source of supply or
combination of sources of supply. Operation of the protection devices shall
not rely upon the connection to the earthed point of the main supply when the
generator is operated as a switched alternative to the main supply.
Where there is no existing earth electrode installed in the electrical installation,
a suitable earth electrode may be installed in accordance with SANS 10199.
When installed, the electrode shall be bonded to the consumer's earth terminal
and to the earthing point on the alternate supply by a conductor of at least half
the cross-section of that of the phase conductor, but not less than 6 mm2
copper, or equivalent. This also applies to a single-phase supply
(see also 5.2.3.1).
NOTE 1 In a TN system earthing of electricity supply, an earth electrode is normally
not required in an electrical installation.
NOTE 2 Protection of photovoltaics can be by means of or surge protective device
(SPD)
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