AS NZS 5112:2015 pdf free download – Tunnel type terminal neutral bars for lowvoltage switchboards-—Requirements for termination of copper conductors up to 50 mm2

AS NZS 5112:2015 pdf free download – Tunnel type terminal neutral bars for lowvoltage switchboards-—Requirements for termination of copper conductors up to 50 mm2.
6.1 General
The bars shall be provided with clamping facilities for securely terminating the conductors used in normal service.
The clamping of conductors shall be secure, not loosen in normal service and not exceed the allowable temperatures.
6.2 Range of conductors and connection requirements
6.2.1 Range of conductors to be connected
The bars shall be provided with means to clamp stranded, solid and flexible copper conductor as shown in Table 1. The conductors shall be unprepared and prepared conductors in accordance with the manufacturer’s instructions.
The maximum size of an unprepared conductor to be clamped shall be at least one size larger than the conductor with a current rating in Table 4 corresponding to the rated current of the neutral bar.
Compliance shall be established in accordance with Clauses 7.3.1 . I and 7.3.1 .2.
NOTE: The test of 7.10 is carried out on the cable sizc corresponding to the rated current in Table 4. e.g. A 250A test is carricd out on a 35 mm2 in Table 4. and not on the maximum connecting capacity of 50 mm2 which relates to Table I, Clause 6.2.2 and 7.3.2.
6.2.2 ,!aximum connecting capacity
The maximum connecting capacity is the largest unprepared stranded copper conductor size in Table I that can be clamped.
Compliance shall be established in accordance with Clause 7.3.2.
6.2.3 Separate term inal.s for individual conductors
The bars shall he provided with separate terminals for connecting each individual incoming and outgoing cable.
Compliance shall be established in accordance with Clause 7.3.3.
6.2.4 Tunnel terminal types
One or more of the following tunnel terminal types, as defined in Clause 3.9. may be used:
(a) Tunnel terminal with screws in direct contact with the conductors.
(b) Tunnel terminal with a ferrule or plate giving indirect pressure on the conductors from the screw.
(C) Saddle terminals for incoming conductors.
Compliance shall be established in accordance with Clause 7.3.4.
Compliance for single screws shall be established in accordance with Clause 7.6.3.
6.5.4 Screws for tunnel terminals and saddle terminals
6.5.4. 1 Number and spacing of screws in direct contact with a conductor
If screws are in direct contact with a conductor, two screws shall be used for the following:
(a) The main incoming neutral, sub main neutral or connections joining one bar to another.
(b) The main earthing conductor (minimum size 4 mm2).
(c) The neutral bar to earth bar or main earth connection (MEN connection).
(d) A PEN (protective earth neutral), e.g. to an outbuilding.
Exception: One screw with a nominal diameter of at least 80% of the tunnel diameter.
The screws shall be spaced far enough apart and the bar sufficiently wide enough to enable access to the screw heads by normal hand tools to allow screws to be tightened to the torques values in Table 2.
Grub screws shall have sufficient length to ensure effective thread purchase and not fall into the tunnel when no conductor is present, e.g. 8.5 mm diameter tunnel, M8 grub screw x 10.2 mm long.
Compliance shall be established in accordance with Clause 7.6.4.
6.5.4.2 Number of screws for tunnel terminals with a plate or frrrule giving indirect
press mire and for saddle terminals
6.5.4.2. 1 Tunnel terminals with a plate or ferrule giving indirect pressure
Tunnel terminals with a plate or ferrule giving indirect pressure may have one screw for the connections specified in Clause 6.5.4.1.
6.5.4.2.2 Saddle terminals
The saddle of a saddle terminal shall be positioned to clamp the conductor across the full diameter of the conductor by a screw on each side of the conductor position.
Compliance shall be established in accordance with Clause 7.6.4.2.
6.6 Mechanical characteristics of screws and bars
6.6.1 General
When screws are tested in accordance with Clause 7.7.1, there shall be no undue damage to the screws or bars and the screw length will ensure the screw reaches the bottom of the tunnel.