knife-switch

knife-switch

A technician operates a knife-switch in an electrical panel.

Definition

Noun: - Electrical device: A "knife-switch" is a type of electrical switch where the moving part (the "blade") is a flat, conducting metal piece that pivots to make or break contact with fixed terminals. It is named for its resemblance to a pocketknife blade, often used in older or industrial electrical circuits.

Usage Examples
  • (Using the switch to disconnect the circuit.)
  • (Multiple switches arranged for control.)
  • (Upgrading from an older switch type.)
Advanced Usage
  • "to throw a knife-switch": to operate the switch by moving its blade into the "on" or "off" position.
    • The technician threw the knife-switch, and the motor hummed to life. (Activated the switch to start the motor.)
  • "knife-switch action": the mechanical motion of the blade pivoting to connect or disconnect.
    • The knife-switch action provides a visual confirmation of the circuit's status. (The visible movement shows if the circuit is open or closed.)
Variants and Related Words
  • Switch (n): a device for making and breaking the connection in an electric circuit.
    • He flipped the switch to turn on the light. (A general term for a circuit control.)
  • Knife-blade (n): the moving metal part of a knife-switch.
    • The knife-blade was corroded from years of use. (The specific component.)
Synonyms
  • Disconnect switch: a switch used to isolate a circuit.
  • Isolator: a device that physically separates a circuit for safety.
Phrasal Verbs
  • Switch off: to disconnect or turn off using a switch.
    • She switched off the knife-switch before repairing the wiring. (Used the switch to cut power.)
  • Switch on: to connect or turn on using a switch.
    • He switched on the knife-switch to restore electricity. (Activated the switch.)
Related Idioms
  • "Throw the switch": to make a decisive change or activate something.
    • The company threw the switch on the new production line. (Started the new operation suddenly.)