AS NZS IEC 60947.7.3-2015 pdf free download.Low-voltage switchgear and controlgear Part 7.3: Ancillary equipment- Safety requirements for fuse terminal blocks.
3 Classification
Fuse terminal blocks are classified as follows:
a) fuse terminal block with separate fuse-carrier, e.g. screw type or plug-in type;
b) fuse terminal block with mechanically coupled fuse-carrier, e.g. hinged type.
4 Characteristics
4.1 Fuse-links
The fuse links shall be in accordance with IEC 60 127-2.
4.2 Rated power dissipation value
4.2.1 Overload and short-circuit protection (nv)
The rated value of power dissipation for overload and short-circuit protection (v) is the maximum permissible power dissipation value of a fuse terminal block under overload and short-circuit conditions related to an ambient temperature of 23 °C.
4.2.2 Exclusive short-circuit protection (vK)
The rated value of power dissipation for exclusive short-circuit protection (vK) is the maximum permissible power dissipation value of a fuse terminal block, which can accept a fuse-link with an equal or lower sustained power dissipation used under exclusive short-circuit conditions and related to an ambient temperature of 23 °C (see Annex B).
NOTE Maximum sustained power dissipation” of a fuse link is given in IEC 60127-1.
4.3 Rated and limiting values
4.3.1 Rated voltages
Subclause 4.3.1 of IEC 60947-7-1 applies.
4.3.2 Void
4.3.3 Standard cross-sections
Subclause 4.3.3 of IEC 60947-7-1 applies.
4.3.4 Rated cross-section
Subclause 4.3.4 of IEC 60947-7-1 applies.
4.3.5 Rated connecting capacity
Subclause 4.3.5 of IEC 60947-7-1 applies with the following addition.
The conductor cross-section specified for the temperature-rise test according to 8.4.5 shall be included in the range of the rated connecting capacity.AS NZS IEC 60947.7.3 pdf download.