If a gate frequently stalls when opening under load, which design parameter is most likely undersized?

• A. Motor torque
• B. Track alignment
• C. Sensor sensitivity
• D. Ground clearance

Answer: (A)

When a gate stalls while opening under load, the critical factor is the motor torque—the turning force the drive system can apply to overcome resistance. To start and continue the movement, the motor’s torque must exceed the resisting torque from the gate, track, rollers, and any friction in the mechanism. If the motor torque is too small for that load, the gate can’t overcome the resistance and simply stalls, especially as it tries to move heavier sections or when starting from rest. In practice, this means the design needs more torque (or a higher gear ratio to trade speed for torque), or reductions in the load or friction so the available torque is sufficient.

Track alignment can influence how smoothly the gate moves by affecting friction, but it doesn’t determine the starting capability as directly as motor torque does. Sensor sensitivity affects how accurately the system detects position or obstacles, not the force needed to start moving. Ground clearance relates to obstacles and clearance, not the torque needed to overcome load.