What is Virtual Encoder?
It actually does not sense obstacles , so "virtual encoder"

But it can predict normal motor current which rises from friction or blocking object or human so it does not crush the victim.

"inversion on obstacles" is obfuscated marketing lingo for " reverse gate motor direction"

Garage door open/closers work the same way by sensing motor current.

p.s. the manual was written by an engineer with tech writer support


the advertisement was written by a non-technically minded salesman



  "Test the gate operator monthly. The gate MUST  reverse on contact
  with a rigid object or when an  object activates a non-contact sensor.
  If necessary,  adjust the force or the limit of travel and then retest
  the gate operator. Failure to properly adjust and retest  the gate
  operator can increase the risk of injury or  death."


@transistor is correct that lots of encoders are listed in datasheet, but little clue as how they work  "The obstacle detection function is achieved by controlling the current absorption and / or through the encoder connected to the motors." p25


ENCODER on motor 1 or motor 2 error  


  appears to be a rotary encoder to measure sudden slight change in speed with high power hydraulics and other protective circuits.



2EASY interface terminals


  is a wire loop (RF method) of sensing proximity of a car steel for auto open, so presumably buried in asphalt/concrete for auto sentry opener on exit.