Rotary Auxiliary Knife Switches

Rotary Auxiliary Switches


Rotary auxiliary knife switches popularly known as wafer switches due to their modular & compact design are very versatile for switching a.s. as well as d.c. resistive & iductive loads. They are used as auxiliary contacts in equipments such as MV & HV - Vacuum Circuit Breakers, Gas Circuit Breakers, Isolators & Various equipments, where it is linked mechanically to the equipment and follows the position as per the linkage. In most cases a straight motion of main contacts is converted into rotational through links & levers to operate the switches.

Features & Specification

  • Knife type of contacting making it suitable for switching d.c. loads.
  • Self cleaning of contacts is done during the operation.
  • Modular design to achieve any number of poles with minimum components.
  • Brass inserts used in threads to endure more than required torque while mounting.
  • Superior insulating material ensures electrical & mechanical stability.


  • Conventional free AIr Thermal Current Rating (lth): 10Amp.
  • Operational Voltage: 220 volts d.c.
  • Operational Current: 2.0 Amp.
  • Utilisation Category: DC113
  • Switching capability: Inductive loads with L/R ratio (time constant) of 20mS.
  • Dielectric Strength: 2.0 kv for 1 minute.
  •  Insulation Resistance: ≥500 Mohm
  •  Mechanical Durability: ≥1,00,000 operations.
  •  Electrical Durability: ≥50,000 operations.
  • Tested as per IEC-62271