NDC Circuit Breaker 900VDC and 1800VDC

Description
Specifications

BRUSH high-speed NDC Circuit Breaker, utilises award winning magnetic actuator technology and provides an innovative DC switchgear solution for OEMs  and Panel builders serving railway traction applications. With 50 years of DC circuit breaker design and manufacturing experience, the BRUSH NDC breaker offers optimal safety, reliability and high-speed performance – the ideal solution to DC applications.

  • High speed operation, direct overload and electrical tripping
  • Simple, reliable mechanism with no mechanical latch
  • Ergonomic, intuitive truck isolation and interlocking
  • Enhanced electrical and mechanical endurance
  • Patented Arc transfer coil
  • Fully bi-directional current interruption
  • Hard wearing main contact material (silver tungsten carbide) ensuring long life
  • Integrated operation with a wide range of protection relay options
  • The patented arc transfer system prevents internal contamination of the circuit breaker compartment and cubicle.
  • The Cold Cathode Arc Chute Assembly (1) dissipates all arcs whilst the transfer coil (2) provides additional magnetic flux across the contact gap, assisting with the interruption of low currents that would otherwise lead to long arcing times
  • Fixed Contact
  • Moving Contact Assembly
  • Primary disconnects
  • The patented Magnetic Latch mechanism provides the primary means of ‘high speed’ tripping of the circuit breaker. Working in conjunction with the Magnetic Actuator, the latch directly holds the circuit breaker contacts closed
  • The Magnetic Actuator is based on a solenoid plunger, and provides the motion required to close the main contacts and to reset the latch device on tripping
  • The uni-directional Direct Acting Release trips the circuit breaker when the current in the main circuit exceeds the overload setting
Rated Voltage V dc 900 1800
Rated Service Current A 4000/6000/8000 4000/6000
Nominal Voltage V dc 750 1500
Power-Frequency Withstand Level kV 9 9
Rated Short-Time Withstand Current kAp/kA 100/71 250ms 100/71 250ms
Rated Track Time-Constant ms 100 63
Rated Short-Circuit Current kAp/kA 180/125 142/100
Bi-directional Critical Current * A 25 25
Mechanical Endurance Number of Operations 50,000 50,000
Breaking Characteristic   High Speed High Speed
Insulation Category   OV4 OV4
Rated Impulse Withstand kVp 20 20
Auxiliary Operating Supply V dc 48 / 50 / 110 / 125 48 / 50 / 110 / 125