Transcript Power cable & conductor terminations

EKAS 2.1.5.1
Power cable and conductor terminations
UEE31307 Certificate III in
Refrigeration and Air Conditioning
Stage 2A
Units: UEENEEPOO1B
Chris Hungerford
Monday, April 13, 2015
Functions of a cable gland
• Hold the cable into positions so that no undue
mechanical stress is placed on the terminations.
• Limits the spread of fire.
Cable glands can be designed to perform these
functions:
»Dust protection
»Water tight seal.
»Explosion protection.
»Vermin proof.
2.1.5.1.A
Cable Glands
• General Purpose Weatherproof
Glands for Armoured Cable
• General Purpose Weatherproof
Glands for Unarmoured Cable
• Cable Glands for Braided EMC
Shielded Cable
2.1.5.1.A
Cable Glands
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PVC Cable Gland Shrouds
Metal Locknuts
Metal Earth Tags
NYLON CABLE GLANDS (IP68)
2.1.5.1.A
AS/NZS-3000:2007, SAA Wiring Rules
3.7 ELECTRICAL CONNECTIONS
3.7.1 General
Connections between conductors and between
conductors and other electrical equipment shall
provide electrical continuity and adequate
mechanical strength.
2.1.5.1.B
Solderless lugs
Ross - Courtney lug.
Stanco lug
2.1.5.1.B
Crimps
Terminating - crimp lugs.
Joining cables of the same size - crimp links.
When crimping it is important that the correct crimp
type lug for the cable and the correct tool for that
lug is used.
AS/NSZ 3000 cl 3.7.2.3.2
2.1.5.1.B
Terminal connections
AS/NZS 3000 cl 3.7.2.4
Blue point connectors (BP)
Line taps.
Articles terminals.
Terminal strips.
Bolted & clamp connectors
2.1.5.1.B
AS/NZS-3000:2007 SAA Wiring Rules
3.7.2.7 Soldered connections
Where a soldered connection is used the
design shall take account of creep,
mechanical stress and temperature rise
under fault conditions.
2.1.5.1.B
Conductor colouring
AS/NZS 3000 Table 3.4
Earth/bonding
Colour
Green/yellow
Neutral
Black
Function
Active
2.1.5.1.C
Light blue
Red Brown, dark Blue, Grey, White, any colour
other than green/yellow, green, black, yellow or
light blue
Stripping of Insulation.
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Avoid using a knife on smaller cables.
Tear the insulation off, don’t cut.
Do not indent any conductor material.
Be sure not to remove excessive insulation.
Remake any damaged insulation.
The only connection for an extension lead is
via an approved plugtop and socket.
2.1.5.1.C
AS/NZS-3000:2007 SAA Wiring Rules
3.7.2.2 Preparation for connection
The insulation on a conductor shall not be
removed any further than is necessary to make
the connection.
For connections between insulated conductors the
connection shall be insulated to provide a degree
of insulation not inferior to that of the conductors.
Any damaged insulation shall be reinstated.
2.1.5.1.C
Insulation of conductors
Yes
• Electrical
insulation tape
• Epoxy kits
• Heat shrink
2.1.5.1.C
No
• Masking tape
• packing tape
• sticky tape
• silicon mastic
AS/NZS-3000:2007 SAA Wiring Rules
3.7.2.6 Mechanical stress
All cables and conductors shall be installed
so that there is no undue mechanical
stress on any connection.
2.1.5.1.C
AS/NZS-3000:2007 SAA Wiring Rules
3.7.2.3.1 Loosening of connections
Connections shall be made so that no
loosening is likely because of vibration,
alteration of materials or temperature
variations to which the connections
are likely to be subjected in normal service.
2.1.5.1.C
Terminations and connections
• Connections must not be soft soldered
before compression terminations.
• Must be seated correctly.
• Free of dirt and oxides.
• Use a suitable lug or connector.
• Insulated to the equivalent of the original
insulation.
• Earth connection must be painted if
exposed to weather
2.1.5.1.C
Further readings
Questions Topic 7 Q1-Q23