Which component is used to provide overload protection for a motor and is often paired with a contactor?

• A. Overload relay
• B. Contactor
• C. Fuses
• D. Thermal switch

Answer: (A)

The test focuses on protecting a motor from drawing too much current while it’s running. An overload protection device is designed to sense excessive current (or heat) and automatically stop the motor by opening the circuit to the motor through the control of the contactor. In a typical motor starter, the overload relay is wired in series with the contactor’s coil (or integrated with the starter). If the motor current stays too high or the motor overheats, the overload relay trips and de-energizes the contactor, which opens the main power contacts and stops the motor. This coordinated action protects the windings from damage due to overheating or overcurrent and can often be reset after the fault is cleared.

Fuses protect conductors and equipment by blowing on a high fault current, but they don’t provide the automatic, motor-specific trip and reset behavior used in motor protection. A thermal switch opens on temperature but isn’t typically tuned to motor overload conditions in a starter circuit. The contactor itself merely switches power; it doesn’t provide overload protection. So the component that is specifically meant to protect the motor from overload and is commonly paired with a contactor is the overload relay.