Chamberlain 120ad Garage Door Opener User Manual


 
ADJUSTMENT STEP 3
Test the Safety Reverse System
TEST
With the door fully open, place a 40mm board on
the floor, centered under the garage door.
Operate the door in the down direction. The door
must reverse on striking the obstruction.
ADJUST
If the door stops on the obstruction, it is not
traveling far enough in the down direction.
Increase the DOWN limit by turning the DOWN
limit adjustment screw counterclockwise 1/4 turn.
NOTE: On a sectional door, make sure limit
adjustments do not force the door arm beyond a
straight up and down position. See the illustration
on page 23.
Repeat the test.
When the door reverses on the 40mm board,
remove the obstruction and run the opener through
3 or 4 complete travel cycles to test adjustment.
If the door will not reverse on the board after
repeated adjustment attempts, call for professional
B&D garage door service.
IMPORTANT SAFETY CHECK:
Repeat Adjustment Steps 1, 2 and 4 after:
Each adjustment of door arm length, limits, or
force controls.
Any repair to or adjustment of the garage door
(including springs and hardware).
Any repair to or buckling of the garage floor.
Any repair to or adjustment of the opener.
ADJUSTMENT STEP 4
Test the Safety Infrared Reversing
Sensors (if installed)
Press the remote control push button to open the
door
.
Place the opener carton in the path of the door.
Press the remote control push button to close the
door
. The door will not move more than 25mm,
and the door control will blink 10 times.
The garage door opener will not close from a remote
if the indicator light in either sensor is off (alerting
you to the fact that the sensor is misaligned
or
obstructed).
If the opener closes the door when the safety
reversing sensor is obstructed (and the sensors
are no more than 150mm above the floor), call for
professional B&D garage door service.
The Chamberlain Group, Inc.
Safety Sensor
Instruction Sheet Page 1 
Protector System Disk #1 (Yellow)
11/5/91 - 1/15/92
Safety Reversing Sensor
Safety Reversing Sensor
Step 3 Test Safety Reverse System SEARS 315-699 (Yellow Disk #2)
Models 53315, 53415, 535156, 53625 & 53699
6/20/89 - 6/27/89
GARAGE DOOR
40mm board laid flat
Without a properly installed safety reversal system,
persons (particularly small children) could be
SERIOUSL
Y INJURED or KILLED by a closing garage
door
.
Safety reversal system MUST be tested every month.
• If one control (force or travel limits) is adjusted, the
other control may also need adjustment.
• After ANY adjustments are made, the safety reversal
system MUST be tested. Door MUST reverse on
contact with 40mm high object on the floor.
Without a properly installed safety reversing sensor,
persons (particularly small children) could be SERIOUSLY
INJURED
or
KILLED by a closing garage door.
The for
ce, as measured on the closing edge ot the door
,
should not exceed 400N (40kg). If the closing force is
more than 400N, the Safety Infrared Reversing Sensor
must be installed. Do not use the force setting procedure
to compensate for a binding or sticking garage door
.
Excessive force will interfere with the proper operation of
the Safety Reverse System or damage the garage door.
WWARNARNINGING
CAUTIONCAUTION
WWARNARNINGING
CAUTIONCAUTION
27
114A2845