EN 50123-2:2003

1 Scope
2 Normative references
3 Definitions
4 Service requirements
5 Characteristics of the circuit breaker
  5.1 Enumeration of the characteristics
  5.2 Type of circuit breaker
  5.3 Rated values and limit values for the main
       circuit
  5.4 Control circuits
  5.5 Auxiliary contacts and circuits
  5.6 Releases
  5.7 Arc voltage
6 Construction
  6.1 General
  6.2 Circuit breaker enclosures
  6.3 Temperature-rises
  6.4 Dielectric strength
  6.5 Electrical and mechanical endurance
  6.6 Operation
  6.7 Corrosion protection
  6.8 Noise emission
  6.9 Cooling
  6.10 Servo-control (where applicable)
  6.11 Other facilities
7 Information and marking
  7.1 Information
  7.2 Marking
8 Tests
  8.1 General
  8.2 Applicable tests and test sequence
  8.3 Performance of tests
Annex A (informative) Information required
  A.1 General
  A.2 Procurement specification
  A.3 Manufacturer's specification
Tables

This part of EN 50123 specifies requirements for d.c. circuit breakers for use in fixed installations of traction systems.NOTE Switchgear assemblies, electromagnetic compatibility (EMC) and dependability are not covered in this part of EN 50123, but by other parts of this standard or by other standards, as indicated in EN 50123-1.