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of two rules (relating to alterations,
additions and repairs) that should help to
reduce the number of homes without
RCD protection:
>
where there is a replacement of the
whole switchboard and its circuit
protective devices due to alteration
or repair then it shall be upgraded
to the latest requirements of RCD
protection; and,
>
where more than 20% of the existing
circuits are added to an installation
then all circuits have to be upgraded
to reflect the latest requirements of
RCD protection.
In the second case, for example, if the
existing residence has two power circuits
and one light circuit (both without RCDs)
and you add a new power and light
circuit then you have exceeded the
20% requirement.
What I like about these rules is
that they put every electrician on
the same page when quoting for a
refurbishment. If either of these rules
applies then the whole switchboard
needs to be upgraded.
Spare a thought for electricians
working on rural properties, with the
installation of pumps and the like.
In recent times there have been
electrocutions down on the farm. After
inquiries were held, it seems that RCDs
could have prevented the fatalities.
One point here is that the motors
involved were up towards the 32A mark.
Until now there has been a requirement
to use 30mA protection on circuits up to
and including 20A.
The biggest upheaval in years for the
installation of RCDs is pending – and
that is for all final sub-circuits up to and
including 32A to be RCD protected. Yes
that’s right, in residential and non-
residential installations.
This has not been overwhelmingly
agreed, but the thought is there and
it does make good sense. The EL001
committee wants greater penetration
of RCD protection in homes, but the
commercial space is equally alluring.
The new revision of AS/NZS 3000 is
nearly upon us. RCD protection is not
the only change, but it is the biggest and
most contentious for many years. Don’t
be shocked when the Wiring Rules are
published at the end of this year.
BY
GARY
BUSBRIDGE
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