AS NZS 61439.6:2016 pdf free

AS NZS 61439.6:2016 pdf free.Low-voltage switchgear and controlgear assemblies
During and after the tests according to 10.2.101.1 to 10.2.101.3, there shall be neither break,nor permanent deformation of the enclosure which would compromise the degree of protection，reduce the clearances and creepage distances to values lower than those specified in 8.3, or impair the correct insertion of incoming and outgoing units.
The protective circuit shall remain functional and the test samples shall withstand the dielectric test according to 10.9.2 of Part 1.
If the same design of the plug assembly is used for a range of tap-off units of different rated currents or of different protective devices, a test on one combination of a BTU and a tap-off unit is considered to be representative of the range. The design of the plug assembly includes the physical characteristics and the material and surface finish (e.g. plating), if applicable.
A tap-off unit incorporating fuses shall be fitted with the maximum size of fuses specified by the original manufacturer. A tap-off unit incorporating a circuit-breaker shall be fitted with a circuit-breaker of the maximum rating specified by the original manufacturer.
Tap-off units can be considered as similar variants of a same design, even if they are intended for different rated currents, if they fulfil all the following conditions:
1) the function of the main circuit is the same (e.g. cable feeder, motor starter);
2) the devices are of the same frame size and belong to the same series;
3) the mounting structure and enclosure of the tap-off unit are of the same type;
4) the mutual arrangement of the device(s) is the same;
5) the type and arrangement of conductors, including the type of connection and conductor material between tap-off unit and BTU are the same;
6) the cross-section of the main circuit conductors has a rating at least equal to that of the lowest rated device in series in the main circuit. Selection of conductors shall be as tested or in accordance with IEC 60364- 5-52. Examples on how to adapt this standard for conditions inside a tap-off unit are given in Annex H of Part 1. The cross-section of bars shall be as tested or as given in Annex N of Part 1.AS NZS 61439.6 pdf free download.