A movable barrier operator having improved safety and energy efficiency
features automatically detects line voltage frequency and uses that
information to set a worklight shut-off time. The operator automatically
detects the type of door (single panel or segmented) and uses that
information to set a maximum speed of door travel. The operator moves the
door with a linearly variable speed from start of travel to stop for
smooth and quiet performance. The operator provides for full door closure
by driving the door into the floor when the DOWN limit is reached and no
auto-reverse condition has been detected. The operator provides for user
selection of a minimum stop speed for easy starting and stopping of sticky
or binding doors.
