Connect The Door Arm To The Trolley - Chamberlain LiftMaster Security+ 3245CM Owner's Manual

ALL ONE-PIECE DOORS
1. Assemble the door arm, Figure 5:
IMPORTANT: The groove on the straight door arm MUST
face away from the curved door arm (Figure 5).
• Fasten the straight and curved door arm sections
together to the longest possible length (with a 2 or
3 hole overlap).
• With the door closed, connect the straight door arm
section to the door bracket with the 5/16"x1-1/4"
clevis pin.
• Secure with a ring fastener.
2. Adjustment procedures, Figure 6:
• On one-piece doors, before connecting the door arm
to the trolley, the travel limits must be adjusted.
Limit adjust ment screws are located on the left side
panel as shown on page 23. Follow adjustment
procedures below.
• Open door adjustment: decrease UP travel limit
- Turn the UP limit adjustment screw
counterclockwise 4 turns.
- Press the Door Control push button. The trolley
will travel to the fully open position.
- Manually raise the door to the open position
(parallel to the fl oor), and lift the door arm to the
trolley. The arm should touch the trolley just in
back of the door arm connector hole. Refer to
the fully open trolley/door arm positions in the
illustration. If the arm does not extend far enough,
adjust the limit further. One full turn equals 2"
(5 cm) of trolley travel.
• Closed door adjustment: decrease DOWN travel
limit
- Turn the DOWN limit adjustment screw clockwise
4 complete turns.
- Press the Door Control push button. The trolley
will travel to the fully closed position.
Figure 6
Inner Trolley
Door Arm
Connector Hole
Door Arm
Closed Door
Outer Trolley
Emergency Release Handle
Inner Trolley
Open Door
CORRECT
Straight
Door
Arm
(Groove
facing out)
Door
Bracket
Clevis Pin
Straight Arm
5/16"x1-1/4"
Figure 5
- Manually close the door and lift the door arm to
the trolley. The arm should touch the trolley just
ahead of the door arm connector hole. Refer to
the fully closed trolley/door arm positions in the
illustration. If the arm is behind the connector
hole, adjust the limit further. One full turn equals
2" (5 cm) of trolley travel.

3. Connect the door arm to the trolley:

• Close the door and join the curved arm to the
connector hole in the trolley with the remaining
clevis pin. It may be necessary to lift the door
slightly to make the connection.
• Secure with a ring fastener.
• Run the opener through a complete travel cycle. If
the door has a slight "backward" slant in full open
position as shown in the illustration, decrease the
UP limit until the door is parallel to the fl oor.
NOTE: When setting the up limit on the following page, the
door should not have a "backward" slant when fully open
as illustrated below. A slight backward slant will cause
unnecessary bucking and/or jerking operation as the door
is being opened or closed from the fully open position.
Correct Angle
Door Arm
22
INCORRECT
Straight
Door
Arm
Curved
Door
Arm
Ring
Fastener
Lock
Washers
5/16"
Bolts
5/16"-18x7/8
Outer Trolley
Door with Backward
Slant (Incorrect)
Curved
Door
Arm
Nuts
5/16"-18
Curved
Door
Arm