For telescoping tandem slide gates, what is recommended to prevent the leading gate from exceeding the speed limit?

• A. The operator must be geared DOWN to prevent the leading gate from exceeding the one foot per second rule
• B. Photobeams are used on both sides of the gates to control speed
• C. The leading gate is mechanically limited with a stopper
• D. The gates are weighted to slow movement

Answer: (A)

The main idea here is controlling the speed of the leading gate so it never exceeds the safe limit. In telescoping tandem slide gates, the leading gate moves first, and if it runs too fast, it can slam or collide with the trailing gate, causing shock loads, misalignment, or safety hazards. Gearing the drive DOWN reduces the motor output to the lead gate, producing a slower, more controlled movement that stays within the one-foot-per-second limit. This direct control of velocity is the most reliable way to meet the speed requirement and maintain smooth, safe operation.

Photobeams can stop movement if something blocks the path, but they don’t regulate how fast the gate travels; they’re safeguards, not speed controllers. A mechanical stopper might limit travel distance but doesn’t actively ensure the gate adheres to a speed limit and can cause abrupt stops that stress components. Weighing the gates isn’t a practical or typical method for maintaining a precise speed in this context.