Chamberlain 1280 - 1/2 HP - Manual (Page 26)

Adjustment Step 4
Test the Safety Reverse System
Test
• Place a one-inch board (or a 2x4 laid flat) on the
floor, centered under the garage door.
• Operate the door in the down direction. The door
must reverse on striking the obstruction.
Adjustment
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.
• Repeat the test.
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 22.
• When the door reverses on the one-inch board,
remove the obstruction and run the opener through
3 or 4 complete travel cycles to test adjustment.
If the door will not reverse after repeated
adjustment attempts, call for professional
garage door service.
1 Inch Obstruction
Failure to test and adjust the safety reverse
system may result in serious injury or death
from a closing garage door. Repeat this test
once a month and adjust as needed.
26
Adjustment Step 3
Test The Protector System ®
• 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 an inch,
and the opener lights will flash for 5 seconds.
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).
The garage door can be closed by pressing and
holding the Door Control push bar or button until
down travel is completed.
Professional service is required if the opener
closes the door when the safety reversing
sensor is obstructed.
Safety Reversing Sensor Safety Reversing Sensor
Without a properly working safety reversing
sensor, persons (particularly children) could be
seriously injured or killed if trapped by a closing
garage door. Repeat this test once a month.
One-Inch board (or a 2x4 laid flat)
WARNING
WARNING
Important Safety Check
Repeat Adjustment Steps 1–4 after:
• Each adjustment of door arm length, force controls
or limit 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.