... 24V DC motor drive unit 3, Rolling code 4, Safety auto-Reverse ,roller door operator garage door opener 1, Inpout ... control , wire switch control. Push button on control box12, Safety : Safety Reversing The drive unit automatically,reverses should the downward movement ... turn off after a 3 minuted delay16,Intruder Alarm : A built in safety alarm inside the control box and will sound continuously ...