Originally Posted by
GCE
I tend to disagree that the regulations need work.
What is needed is for suitable qualified people to do the work and for users of electricity to learn that Electrical contractors need to be registered before allowing them to work on their installations.
Clause 5.4.3 under fundamentals in the beginning of the regulations is clear that equipment shall be suitable rated. If you install a 63Amp earth leakage isolator type, then there needs to be at least a 63Amp C/breaker installed before the ELU.
Same way that you keep seeing 63Amp D/Pole isolators in D/boards with 80Amp C/breakers from municipality side - COC is invalid as the isolator is not suitable protected.
To go one further , the reg states " It shall also be able to carry the current that is likely to flow under abnormal conditions and for the period that the current is likely to flow." If you have a CB manufactured by A protecting an ELU manufactured by B , how do you know that the ELU will withstand the tripping curves from a different manufacture unless it has been tested as such ?
5.4.3 Current
The equipment shall be suitable for operation at the maximum steady (r.m.s.)
current to which it is likely to be subjected. It shall also be able to carry the
current that is likely to flow under abnormal conditions and for the period that
the current is likely to flow.
NOTE The period that an abnormal current will flow is equal to the operating time of
any protective device.
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