________ must never be used to interrupt current flow in circuit.

________ must never be used to interrupt current flow in circuit.

• A. Switches
• B. Fuses
• C. Disconnects
• D. Relays

Answer: (C)

Disconnection devices are built to provide a visible isolation point for safety, not to interrupt current during operation. They’re designed to be opened only after the circuit has been de-energized by a protective device, so that arcing is minimized and the circuit behind the disconnect is guaranteed to be safe to work on. Opening a disconnect while live can allow a high-energy arc to form, may not extinguish quickly, and can leave equipment energized even though the switch looks open. Protective devices like fuses or circuit breakers are the ones engineered to interrupt fault or overload currents reliably; the disconnect simply proves the circuit is isolated after those protective devices have done their clearing. Relays are control components, and switches are used for manual operation, but neither is the designated interruption device for fault current in the same way a protective device is.

Disconnection devices are built to provide a visible isolation point for safety, not to interrupt current during operation. They’re designed to be opened only after the circuit has been de-energized by a protective device, so that arcing is minimized and the circuit behind the disconnect is guaranteed to be safe to work on. Opening a disconnect while live can allow a high-energy arc to form, may not extinguish quickly, and can leave equipment energized even though the switch looks open. Protective devices like fuses or circuit breakers are the ones engineered to interrupt fault or overload currents reliably; the disconnect simply proves the circuit is isolated after those protective devices have done their clearing. Relays are control components, and switches are used for manual operation, but neither is the designated interruption device for fault current in the same way a protective device is.