Understanding how gate openers work:

How does a Swing Gate opener work? DC & Solar.

A solar gate opener works via the wireless remote, a signal is sent to the receiver in your control box. The receiver is sent a signal via the remote that activates the motor movement to open or close, the 20 watt solar panel is keeping the battery charged.

20 Watt Solar Panel Gate Openers

These motors on solar are DC.Naturally the articulated arm is attached to the gate, so when the signal is received the arm pull the gate to the position required. In all cases with swing gates, the gate must be in good working order in the manual mode. Most gate systems have a force mode,enabling the gate to go into auto reverse when feeling an obstruction . 

How does a Sliding Gate opener work?  DC & Solar. 

Sliding gate motors have rack and pinion movement,rack (toothed) is fixed the the bottom section of the gate that covers the whole gate span, the sliding gate motor has a drive cog (toothed) that rotates when the motor is activated via the remote as per the swing gate opener.

It is engaging with the gate rack attached to the gate, as the motor is fixed firmly to the ground, the rack is above the drive cog with the two engaged at all times, this enables the gate to be moved in a foward or backward movement until the limit is reached. As per the swing gate the sliding gate must be free moving in manual mode to be motorised the correct way.