What happens when the operating coil of a relay is energized?

• A. The relay opens the circuit
• B. The relay remains in its de-energized state
• C. The relay closes the circuit
• D. The relay activates safety mechanisms

Answer: (C)

When the operating coil of a relay is energized, it creates a magnetic field that attracts a movable armature within the relay. This movement of the armature typically closes one or more contacts in the relay. As a result, the circuit that the relay controls is closed, allowing electrical current to flow through it. This function is essential in many applications where a low-power signal is used to control a higher-power circuit, effectively acting as an electrically operated switch.

In contrast, energizing the coil does not lead to the relay remaining in its de-energized state, which would occur if no current were flowing through the coil. The primary role of a relay is to open or close circuits based on the input it receives via the coil. The activation of safety mechanisms may take place in some specific relay designs, but it is not a universal function and is not the primary effect of energizing the coil.