Which statement about remote-control switching systems is true?

• A. They rely on a split low-voltage coil to actuate line-voltage contacts.
• B. They do not use a coil at all.
• C. They require direct manual switching at the load.
• D. They use a high-voltage coil to drive contacts.

Answer: (A)

Remote-control switching uses a relay or contactor that is energized by a low-voltage control circuit. When the control voltage energizes the coil, a magnetic field pulls the contacts together to complete the circuit on the load side, which is at line voltage. This separation between the low-voltage control and the high-voltage power circuit lets a small signal safely operate a large load, providing isolation and convenient control from a distance or from automation equipment. That’s why relying on a low-voltage coil to actuate line-voltage contacts is the true description.

The other ideas don’t fit because there is indeed a coil in remote-control switching, so saying there’s no coil isn’t accurate. The system doesn’t require manual switching at the load when controlled remotely. And using a high-voltage coil would negate the safety and practicality benefits of separating control and power circuits.