For maximum safety of equipment, overload relays should be?

• A. Manual reset type
• B. Included in contactors
• C. Not affected by motor current
• D. Automatic reset type

Answer: (A)

Requiring a manual reset on an overload relay is about ensuring a deliberate, safe restart after a fault. When an overload or fault occurs, the circuit trips and blocks re-energizing until a human operator acknowledges the issue and resets it. This pause gives time to inspect and fix the problem, remove any hazards, and verify that it’s safe to restart. If the relay could reset automatically, the motor might restart on its own as soon as conditions permit, which can surprise operators and potentially cause injury or equipment damage. Being integrated with a contactor is a common design choice, but it doesn’t by itself guarantee safety. An overload relay must still respond to motor current to provide protection, and claiming it isn’t affected by motor current would defeat that purpose. Automatic reset removes the safeguard of a conscious restart, so the manual reset type offers the safest approach.