Which statement is true about Harmonic Arm Swing Gate Operators?

• A. They use a fixed crank arm and extension arm to move the gate
• B. They rely on hydraulic cylinders to move the gate
• C. They cannot be pad mounted
• D. They do not provide limit position settings

Answer: (A)

Harmonic Arm Swing Gate Operators move the gate using a fixed crank arm attached to the drive shaft plus an extension arm that connects to the gate, converting rotary motion into the gate’s swing. This mechanical linkage defines the gate’s travel arc and provides a predictable, controlled movement with a set travel length and force through the crank-extension geometry.

That’s why this statement is the best fit: the design relies on a fixed crank arm and extension arm rather than other actuation methods. Hydraulic cylinders describe a linear actuation method, which this design does not use. The note about pad mounting isn’t universally true for all models, and gate operators generally include adjustable limit settings to define open and closed positions, so claiming there are no limit settings isn’t accurate.