IntroductionAuto-drop-arm function: The middle arm can drop down automatically (default) or free passing when the power is off.Manual-lift-arm function: The middle arm needs to lift manually when the power is on again.Multi-alarm function: When arms are pushed by force illegally, alarm will be triggered automatically and arms will be set locked (the duration of the alarm and lock is adjustable by software).Automatic-rotation function: Once an open signal is given, the arms will rotate automatically.Anti-reverse-rotation function: Reverse rotation will be forbidden once the arms have moved to pre-set degree (adjustable by software) from home.Emergency-escape function: The middle arm will drop down automatically by pressing the emergency button which can be remote-controlled whether the power is on or not.