Chamberlain LGJ Owner's Manual page 9

IMPORTANT NOTE: To avoid danger of possible damage to the door and operator, limit switches must be
adjusted to their approximate positions before applying power to the operator.
WARNING
NEVER PLACE HANDS OR TOOLS INSIDE
OPERATOR OR NEAR MECHANISM UNLESS
POWER IS OFF!!
A. Set Limit Direction Switch
Open the cover on the electrical enclosure and locate
CAUTION
dip switch SW1 on circuit board. The direction of the
limit travel is determined by the switch SW1 - pole #2
setting.
If your operator is mounted Motor Side Up:
Set dip switch SW1 - pole #2 to "ON" position.
If your operator is mounted Motor Side Down:
Set dip switch SW1 - pole #2 to "OFF" position.
NOTE: See Mounting Options on page 5 to verify the
correct mounting application.
As determined by SW1 - pole 2 setting above, locate
your OPEN and CLOSE limit switches. See the figure
below for switch layout.
For Motor Side Up Mounting: Limit switch -A- is the
OPEN limit. Limit switch -B- is the CLOSE limit.
For Motor Side Down Mounting: Limit switch -A- is
the CLOSE limit. Limit switch -B- is the OPEN limit.
Limit Switch Layout
Limit Nut
Limit Switch -A-
(Top Switch)
Limit Switch -A-
(Bottom Switch)
LGJ LIMIT SWITCH ADJUSTMENT
Limit Switch -B-
(Top Switch)
Auxiliary limit switches to control other functions are
WARNING
also present and should not be confused with the -A-
and -B- limit switches. There are two(2) limit nuts on
the threaded shaft that transverse the shaft as the
operator opens and closes the door. When a limit nut
nears the end of the shaft, it activates a switch(es).
B. Manually raise the door to a nearly open position.
(see page 17, Manual Operation)
C. Depress the limit nut retaining bracket away from
WARNING
the slots in the limit nuts, and manually rotate to the
OPEN limit nut until it depresses the OPEN limit
switch lever (you can hear the switch click when the
switch contacts transfer). Release the retaining
bracket and be sure it engages in the slots of both
limit nuts.
D. Manually lower the door to a nearly closed
position, and repeat step C with the CLOSE (right)
limit nut.
E. Test Limit Travel
Manually move the door to a half-open position to
avoid damage due to incorrect (dip switch setting)
limit travel. When power is applied, it will cause the
door to OPEN when the limit nuts are traveling in the
direction of the CLOSE limit switch or vice versa. In
either instance, the limit nuts will travel past the limit
switch and may cause damage to both the door and
operator. See Step A for correct setting.
F. After completing the wiring connections on pages
11 thru 13, refer back to step C above for adjustment
of limit switches to their final, exact position.
Limit Switch -B-
(Bottom Switch)
9
If you operator is mounted Motor
Side Up: Set dip switch SW1 - pole
#2 to "ON" position
If your operator is mounted
Motor Side Down: Set dip switch
SW1 - pole #2 to "OFF" position.
When SW1 - pole 2 position is
"ON": Limit switch -A- is the OPEN
limit. Limit switch -B- is the close
limit.
When SW1 - pole 2 position is
"OFF": Limit switch -A- is the
CLOSE limit. Limit Switch -B- is the
OPEN limit.
Dip Switch
SW1