During high-speed opening, R2 resistance is _______.

During high-speed opening, R2 resistance is decreased. This phenomenon occurs because as the elevator doors begin to open rapidly, the door operator's control system adjusts to increase the efficiency of the motor's performance. By reducing the resistance in R2, the control system allows for more power to be delivered to the motor, facilitating a quicker and smoother opening motion.

The decrease in R2 resistance is critical for ensuring the doors open effectively and rapidly, enhancing the overall performance and functionality of the elevator. This adjustment is part of the door operator's design, which is optimized for various scenarios, including high-speed operations, to ensure safety and reliability. The understanding of how resistance plays a role in the performance of elevator door systems is crucial for technicians and engineers working with these systems.