AS NZS 5112:2015 pdf free
AS NZS 5112:2015 pdf free.Tunnel type terminal neutral bars for low voltage switchboards
Screws shall be of a metal having， under the conditions occurring in the equipment,mechanical strength, electrical conductivity and resistance to corrosion adequate for their intended use. The threads shall be metric.
NOTE: Typical examples of suitable metals, when used within the permissible temperature range and under normal conditions of chemical pollution, are as follows:
(a) An alloy containing at least 50% copper (bras). These may be specified in some tropical areas.
(b) Steel provided with an electroplated coating of zinc with coating having a thickness of at least 5 um.
(e) Steel provided with an electroplated coating of nickel and chromium having a thickness of at least 20 um.
(d) Steel provided with an electroplated coating of tin having a thickness of at least 12 um.
(e) Steel provided with an electroplated coating of copper, nickel and brass having a thickness of approximately 10 μm.
Compliance shall be established in accordance with Clause 7.5.
The distance from edge of a single screw to the end of blind hole shall be sufficient to ensure that all strands at the end of an unprepared conductor are clamped.
The distance shall be at least half the tunnel hole diameter.
NOTES:
1 The strands at the end of an unprepared conductor may be unequal lengths which require a distance to ensure all strands are clamped.
2 The holes in tunnel terminals are normally through holes where the conductor enters on one side and exits on the other side.
A hole drilled within a bar, with no exit, is a blind hole.A through hole which is blocked by an external barrier is regarded as a blind hole.Compliance shall be established in accordance with Clause 7.8.1.
The bar’s smallest cross-section, the terminal connections and the terminals for conductors used for joining bars together shall have a maximum temperature rise of 45 K when tested in accordance with Clause 7.10, in open air with the marked rated current flowing through the bar and test conductors.AS NZS 5112 pdf free download.
