Which statement best describes manual reset overload relays?

Which statement best describes manual reset overload relays?

• A. They automatically reset after a fault
• B. They require manual reset after a fault
• C. They reset after a temperature drop
• D. They are not used for motor protection

Answer: (B)

Manual reset overload relays protect motors by tripping when current exceeds a set limit, and they stay tripped until someone manually resets them. This means after a fault, the circuit won’t restart on its own—the operator must intervene to reset the device and then re-energize the motor. This behavior is what makes them manual reset, distinguishing them from relays that reset automatically after a fault or conditions like a temperature drop. They are indeed used for motor protection, aligning with their role in preventing motor damage due to overload.

Manual reset overload relays protect motors by tripping when current exceeds a set limit, and they stay tripped until someone manually resets them. This means after a fault, the circuit won’t restart on its own—the operator must intervene to reset the device and then re-energize the motor. This behavior is what makes them manual reset, distinguishing them from relays that reset automatically after a fault or conditions like a temperature drop. They are indeed used for motor protection, aligning with their role in preventing motor damage due to overload.