electrical services minimum requirement - NSW Public Works

Part 2 - Switchboards and Associated Equipment
Earth - green-yellow
Cables listed in two colours (eg brown-red) shall consist of a base colour (ie brown) and a
spiral trace colour (ie red). Cable trace colours shall cover between 20% and 40% of the
cable surface and extend the full length of the cable.
As an alternative for cables above 50mm 2 , all double insulated cables, phase
identification may be 25 wide heat shrink bands of the colours tabulated above applied at
each end and at not more than 500 intervals along the entire run.
Identification
(a) Control Wires
All control wires shall be individually identified at each end. All control cables shall
have the same identifying number over its entire length even when it passes in and
out of a terminal block.
(b) Multicore Control Cables
Each cable core shall be individually identified with a number in numerals and spelt
out in letters. Such identification shall be in black on to the cable cores during
manufacture. Cable cores shall be consecutively numbered.
(c) Plastic Cable Ferrules
Cable cores which do not have integral number identification shall be identified
using proprietary cable ferrules. Cable ferrules shall be flexible plastic sleeve type
Z type with indelible alphanumerics. The cable ferrules shall be designed for the
cable core diameter. The use of Critchley Multi-Mark and Grafoplas identification
systems is acceptable.
(d) Cable Sheaths Identification
All cable sheaths shall be identified at both ends. Identification shall include cable
number prefixed by J for instrumentation, C for control and P for power, circuit
name (e.g. Pump 1) and type and size of cable (e.g. 3C + E 2.5 mm²).
Identification shall be neat, permanent and legible and the following will be
acceptable:
- Stamped aluminium tags
- Proprietary write-on tags
(e) Visibility
Cable and core identification shall be fully legible and visible from the front of the
switchboard, control panel, equipment etc. ferrules, embossed alphanumerics,
tags, etc., shall be arranged such that all letters and numerals are in line and can
be readily read from the front without manipulation. Alphanumerics shall be
vertically upright on horizontal cables and cores, and shall be read from the right
hand side on vertical cables and cores.
205.3 Large Cables (Cables above 6mm²)
Not more than one cable shall terminate in a tunnel terminal, and not more than two
cables shall terminate at any other connection point or terminal.
Active links shall comply with paragraphs (a) to (d) of Clause 206.2.
Large cables shall not be run to hinged panels or doors.
In addition to the cable supports described in Clause 205.1, rigid non-metallic fixings to
the switchboard cubicle shall be provided within 200 of all terminations and at not more
than 400 intervals along the entire run.
If the cables are in a duct, the intermediate fixings shall be within the duct.
To minimise eddy current effects metal cable saddles shall not be fitted over single core
cables rated over 300A.
Page 40 MEW E101