What occurs during a momentary switch press in a seal-in circuit?

In a seal-in circuit, pressing the momentary switch initiates the flow of current, which then operates a relay or contactor. This relay or contactor typically has a 'seal-in' or 'holding' contact that allows current to continue flowing even after the momentary switch is released. As a result, the circuit remains energized until another action is taken, such as a manual reset or another interrupting condition occurs.

This feature is essential for maintaining operation without the need for continuous pressure on the switch. It ensures that once the switch is pressed, the current flow continues uninterrupted until deliberately cut off. This characteristic is crucial for various applications where a sustained operation is required after an initial command.

Other options suggest scenarios where current would not remain flowing after the momentary switch is released, which misrepresents the fundamental operation of a seal-in circuit.