electrical services minimum requirement - NSW Public Works

Part 1 - Installation
105.4 Indication of Cables Under Roads and Paths
Where a cable passes under a road or path, place a marking plate at each side of the
road or path. Engrave the marking plate as detailed in Clause 105.3 and fixed to a
concrete block approximately 150 x 150 x 300 deep.
Alternatively, marking plates may be fixed to the kerb of a kerbed road.
105.5 Indication of Terminated Conduits
Where conduits are terminated underground and beyond the perimeter of a building or
paved area, fix a marking plate to a concrete block approximately 150 x 150 x 300 deep
located above the termination point. Engrave the plate with the words "ELECTRIC
CONDUIT TERMINATED UNDER".
106 CABLES AND WIRING
106.1 Generally
Supply cables, terminations, fittings and accessories suitable for the voltage, current,
frequency, temperature and environmental duty.
Terminate copper conductors either into tunnel type connectors or by suitably sized lugs
sweated or crimped in an approved manner.
Ross Courtney (solderless) terminations may be used on conductors up to 4mm 2.
No joints in cables can be made between equipment terminal connections unless
required by AS 3000.
Stranded conductors are required above 1mm².
Cable colours and codes are as follows:
red, white, blue - active conductors in multi-phase mains and circuits.
red - active conductors in single phase mains and circuits.
black - neutral conductor.
white (numbered cores) - control circuit cabling outside of switchboards.
green-yellow - earth wires.
Refer to Clause 205.2 for Cable Identification.
Carry insulation resistance testing out with a minimum 1000 V DC testing instrument.
Make final connections to equipment generally using flexible conduit, seal the flexible
conduit at each end using expanding foam or a cable gland.
All cables to be PVC insulated PVC sheathed circular unless otherwise specified.
106.2 Consumer's Mains and Metering
Run the consumer's mains underground from the Point of Attachment as sheathed
copper cable in conduit for its entire length to the main switchboard (in the case of current
transformer metering) or the Supply Authority metering panel (in the case of Direct
Metering).
The minimum size of consumers mains is 16mm², however the following requirements
apply:-
(a) Current carrying capacity to suit the maximum demand and any stated future
extensions with an excess current carrying capacity of 30% minimum.
(b) Be sized so the voltage drop is less than 1.5% at plant future maximum demand at
(a) above.
(c) Be either single core PVC/PVC cables or four core PVC/PVC cable XLPE
insulation may be used.
Page 10 MEW E101