scope:

This Standard specifies requirements and methods of test for tunnel type terminal neutral bars for low voltage switchboards for termination of copper conductors up to 50 mm². It applies to bars of the tunnel terminal type for connection to copper conductors-

(a) of the rigid, stranded or flexible type; and

(b) with a cross-sectional area of 1.0 mm² up to and including 50 mm².

NOTES:

1 Preferred current ratings are 63 A, 80 A, 100 A and 125 A.

2 This Standard is for tunnel terminal type neutral bars for use as components in switchboards, panel boards, load centres, meter boxes and the like.

3 The current ratings in this Standard apply to bars with a maximum temperature rise of 45 K when tested at ambient temperature in open air. The ratings obtained in this Standard are applicable to switchboards with an internal air temperature rise of up to 25 K.

NOTE: Refer to Appendix A of this document for further details.