IEC 60947-7-3:2009

FOREWORD
INTRODUCTION
1 General
  1.1 Scope
  1.2 Normative references
2 Definitions
3 Classification
4 Characteristics
  4.1 Fuse-links
  4.2 Rated power dissipation value
      4.2.1 Overload and short-circuit protection (P[V])
      4.2.2 Exclusive short-circuit protection (P[VK])
  4.3 Rated and limiting values
      4.3.1 Rated voltages
      4.3.3 Standard cross-sections
      4.3.4 Rated cross-section
      4.3.5 Rated connecting capacity
      4.3.6 Working voltage
5 Product information
  5.1 Marking
  5.2 Additional information
  5.3 Marking on the packing unit
6 Normal service, mounting and transport conditions
      6.1.1 Ambient temperature
7 Constructional and performance requirements
  7.1 Constructional requirements
      7.1.1 Clamping units
      7.1.2 Mounting
      7.1.3 Clearances and creepage distances
      7.1.4 Terminal identification and marking
      7.1.6 Rated cross-section and rated connecting capacity
      7.1.8 Actuating conditions
  7.2 Performance requirements
      7.2.1 Mechanical requirements during actuation
      7.2.2 Electrical requirements
      7.2.3 Thermal requirements
  7.3 Electromagnetic compatibility (EMC)
8 Tests
  8.1 Kinds of test
  8.2 General
  8.3 Verification of mechanical characteristics
      8.3.1 General
      8.3.2 Attachment of the fuse terminal block on its support
      8.3.3 Mechanical properties of clamping units of a fuse
            terminal block
      8.3.4 Compatibility between fuse terminal blocks and the
            fuse-link
      8.3.5 Mechanical strength of the connection between the
            terminal block base and the fuse-carrier
  8.4 Verification of electrical characteristics
      8.4.1 General
      8.4.3 Dielectric tests
      8.4.4 Contact resistance
      8.4.5 Temperature rise of clamping units
      8.4.7 Ageing test (for screwless-type fuse terminal
            blocks only)
  8.5 Verification of thermal characteristics
      8.5.1 General
      8.5.2 Rated power dissipation
      8.5.3 Durability
      8.5.4 Needle flame test
  8.6 Verification of EMC characteristics
Annex A (normative) Gauges
Annex B (informative) Power dissipation values P[V] and P[VK]
Annex C (normative) Order of tests and number of
        specimens
Bibliography

IEC 60947-7-3:2009 applies to fuse terminal blocks with screw-type or screwless-type clamping units for the connection of rigid (solid or stranded) or flexible copper conductors for the reception of cartridge fuse-links in accordance with IEC 60127-2, intended primarily for industrial or similar use in circuits not exceeding 1 000 V a.c., up to 1 000 Hz or 1 500 V d.c., and having a maximum short-circuit breaking capacity of 1 500 A. They are intended for installation in electrical equipment with enclosures which surround the fuse terminal blocks to such an extent that they are accessible only with the aid of a tool. For certain applications, for example in control circuits, the fuse terminal blocks may be designed exclusively for short-circuit protection. The object of this standard is to specify safety requirements and test methods for the mechanical, electrical and thermal characteristics of fuse terminal blocks, to ensure the compatibility between terminal blocks and standardized fuse-links. This standard may be used as a guide for
- fuse terminal blocks requiring the fixing of special devices to the conductors, for example quick connect terminations or wrapped connections, etc.;
- fuse terminal blocks providing direct contact to the conductors by means of edges or points penetrating the insulation, for example insulation displacement connections, etc.
Where applicable in this standard, the term "clamping unit" has been used instead of the term "terminal". This is taken into account in case of reference to IEC 60947-1. The main technical modifications of this standard since this previous publication are listed below:
- requirements regarding clearances and creepage distances replaced by reference to Annex H of IEC 60947-1;
- requirements for the test of the mechanical strength of the clamping units improved in 8.3.3.1;
- requirements for tightening torques for the tests improved and referenced to Table 4 of IEC 60947-1;
- requirements for the resistance and the dimensions of dummy fuse-links specified in 8.5.2.5.

This publication shall be read in conjunction with IEC 60947-1:2007 and IEC 60947-7-1:2009.