The three basic components of a time-delay relay are the coil, the contacts, and the _____________________ mechanism.

• A. Timing
• B. Switching
• C. Electromagnetic
• D. Power

Answer: (A)

The main idea is that a time-delay relay adds a controlled delay between energizing the coil and the switching of the contacts. The three basic parts are the coil, the contacts, and the timing mechanism. The coil creates the magnetic field to move the contacts, but the timing mechanism is what actually controls how long the relay waits before the contacts change state. This timing element can be mechanical, thermal, or electronic, such as a RC network, a heated element, or a dedicated timer circuit. Without this mechanism, the relay would operate immediately when energized, not delay the action. The other options describe aspects the relay already performs (electromagnetic action, switching the contacts) or the power source, but they don’t account for the delayed timing feature.