BS 7657:1993

Committees responsible
Foreword
Specification
1. General
1.1 Scope
1.2 Vacant
1.3 References
2. Definitions
3. Classification
4. Characteristics
4.1 General
4.2 Type of equipment
4.3 Rated and limiting values for the main
          circuits
5. Product information
5.1 Nature of information
5.2 Marking
5.3 Instructions for installation, operation and
          maintenance
6. Normal service and mounting conditions
6.1 Normal service conditions
6.1.1 Ambient air temperature
6.2 Vacant
6.3 Mounting
6.3.101 Type A fuses
6.3.102 Type B fuses, terminal blocks and inter-
          connecting units
7. Constructional and performance requirements
7.1 Constructional requirements
7.1.1 Materials
7.1.2 Current carrying parts and their connections
7.1.2.101 Fuse-carriers
7.1.2.102 Fuse-bases
7.1.3 Clearances and creepage distances
7.1.4 Vacant
7.1.5 Vacant
7.1.6 Vacant
7.1.7 Terminals
7.1.7.1. Constructional requirements
7.1.7.2 Connecting capacity
7.1.7.3 Connection
7.1.7.4 Terminal identification and marking
7.1.8 Vacant
7.1.9 Vacant
7.1.10 Enclosures for equipment
7.1.10.1 Design
7.1.11 Degrees of protection of enclosed equipment
7.2 Performance requirements
7.2.1 Vacant
7.2.2 Temperature-rise
7.2.2.101 Long-term contact stability
7.2.2.102 Mechanical endurance
7.2.3 Dielectric properties
7.2.101 Performance on overload and short circuits
8. Tests
8.1 Kinds of tests
8.1.1 General
8.1.2 Type test
8.2 Conformity with constructional requirements
8.2.1 Materials
8.2.1.101 Flammability test
8.2.2 Equipment
8.2.2.101 Impact test
8.2.2.102 Mechanical tests on security of sealing lugs
8.2.3 Enclosures for equipment
8.2.3.101 Degree of protection test
8.2.4 Mechanical properties of terminals
8.2.4.101 Terminal torque test
8.3 Performance
8.3.1 Test sequences
8.3.2 General test conditions
8.3.2.1 General requirements
8.3.2.2 Test quantities
8.3.2.3 Vacant
8.3.2.4 Test reports
8.3.3 Performance under no load, normal load and
          overload
8.3.3.1 Vacant
8.3.3.2 Vacant
8.3.3.3 Temperature-rise
8.3.3.4 Dielectric properties
8.3.4 Performance under short-circuit conditions
          for type A and type B fuses
Annexes
AA. (informative) Guide to the uninterrupted rated
          current of fuses under various conditions of
          installation
BB. (normative) Type test sequence for fuses
Tables
101. Peak test current
102. Type tests
103. Maximum temperature-rise at rated current
104. Values of overload test current
AA1. Examples of derating for typical installation
          methods
Figures
101. Pillar terminal with direct pressure
102. Apparatus for impact test
103. Mechanical tests on security sealing lugs
List of references

Specifies the requirements for fuses (cut outs), ancillary terminal blocks and interconnecting units up to 100 A ratings, for the protection of power supplies to buildings. Coverage includes definitions, product information, and constructional and performance requirements.