Craftsman 139.53664SRT2 - Manual (Page 21)

The Safety Reversing System
information you'll need before you begin the installation of the safety reversing sensor.
The safety reversing sensor must be connected
and aligned correctly before the garage door
opener will move in the down direction. This is a
required safety device and cannot be disabled.
Installation procedures are the same for sectional
and one-piece doors.
A
Without a properly working safety reversing
sensor, persons (particularly children) could
be injured or killed by a dosing garage door.
Read and follow all instructions.
To protect small children, install the safety
reversing sensor so that the beam will be no
higher than 4"-6" above the garage floor.
Disconnect power to the garage door opener
before installing the safety reversing sensor.
Be sure power to the opener is disconnected.
The sending eye transmits an invisible light beam to
the receiving eye. The units can be installed on
either side of the garage door as long as the sun
never shines directly into the receiving eye lens.
Look at the label on the connector end of each case
to identify the sensors.
The brackets must be connected and fastened so
that the sending and receiving eyes face each other
as shown in Figure 1.
If an obstruction breaks the light beam while the
garage door is closing, the door will stop and
reverse to full open position and the opener lights
will flash for 5 seconds.
The brackets must be securely fastened to a solid
surface such as the studs on either side of the door,
or add a piece of wood at each location if installing in
masonry construction.
The invisible light beam path must be unobstructed.
No part of the garage door (or door tracks, springs,
hinges, rollers or other hardware) can interrupt the
beam while the door is closing. If it does, use a piece
of wood to build out each sensor mounting location to
the minimum depth required for light beam clearance.
Figure 1 : Facing the door from inside the garage
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