During the opening sequence, voltage on terminal A2 of the door motor armature is _______.

During the opening sequence of an elevator door, terminal A2 of the door motor armature is supplied with positive voltage. This positive voltage is essential as it indicates that the motor is being activated to perform its task of opening the door.

The motor requires a specific polarity to function correctly, with positive voltage allowing current to flow through the armature in the appropriate direction. This leads to rotation or movement, enabling the elevator door to open smoothly. The voltage is integral to the motor's operation, ensuring it accomplishes its designated function effectively during this phase.

Understanding the operation of the door motor requires recognizing that the voltage polarity dictates the movement of the motor, making positive voltage on terminal A2 crucial during the opening sequence.