Chamberlain LJ8950W User manual

For Light Duty Commercial Use
Install On Rolling Doors Only
NOT FOR RESIDENTIAL USE
Light-Duty Jackshaft Operator
for Rolling Doors
Model LJ8950W
LiftMaster
300 Windsor Drive
Oak Brook, IL 60523
• Please read this manual and the enclosed safety materials carefully!
• The door WILL NOT CLOSE unless the Protector System®is connected and properly
aligned.
• Periodic checks of the operator are required to ensure safe operation.
• The model number is located on the front cover of the operator.
• DO NOT exceed 10 complete cycles of door operation per hour.
• DO NOT use with sectional type doors.
This product is to be installed and serviced by a trained door systems technician only.
This product may require adjustments to door springs and or track configurations.
2 YEAR WARRANTY
After Installation, Please Leave with Customer
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2
Table of Contents
Introduction 2
Safety Symbol and Signal Word Review ...2
Preparing Your Door.................................3
Carton Inventory .......................................5
Hardware ..................................................5
Additional Items You May Need................5
Assembly 5
Attach the Drive Sprocket .........................5
Attach Mounting Brackets.........................5
Installation 6
Introduction ..............................................6
Live Shaft Door Requirements..................7
Dead Shaft Door Requirements.................8
Install the Door Sprocket ..........................9
Mount the Door Operator........................10
Attach the Emergency Release Rope
and Handle..............................................12
Install the Single Button
Control Station .......................................12
Install The Protector System...................13
Install the Light
Curtain (Not Provided)............................16
Connect Power........................................17
Install the Battery Backup
(Not Provided) ........................................19
Adjustments 20
Program the Travel Limits.......................20
Test the Safety Reversal System.............21
Test the Protector System.......................21
To Open the Door Manually ....................22
Operation 23
Using Your Door Operator ......................24
Programming 25
Remote Control (Not Provided)...............25
To Erase the Memory..............................25
Maintenance 26
Care of Your Door Operator ....................26
Troubleshooting 27
Diagnostic Chart .....................................27
Additional Troubleshooting.....................28
Repair Parts 29
Installation Parts.....................................29
Door Operator Parts................................29
Accessories 30
Contact Information 30
Introduction
When you see these Safety Symbols and Signal Words on the following pages, they
will alert you to the possibility of serious injury or death if you do not comply with the
warnings that accompany them. The hazard may come from something mechanical or
from electric shock. Read the warnings carefully.
When you see this Signal Word on the following pages, it will alert you to the possibility
of damage to your door and/or the door operator if you do not comply with the cautionary
statements that accompany it. Read them carefully.
Mechanical
Electrical
Safety Symbol and Signal Word Review
This door operator has been designed and tested to offer safe service provided it is installed, operated, maintained and tested in strict
accordance with the instructions and warnings contained in this manual.
WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause
cancer or birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov

3
Introduction
Preparing Your Door
BEFORE YOU BEGIN:
• Remove any ropes connected to door.
• Raise and lower the door to ensure
the door does not bind or stick and
is properly balanced. If your door
binds, sticks or is out of balance refer
to the door manufacturer for more
information. Doors heavier than 650
lbs. should NOT open or fall rapidly.
For live shaft type doors the drive
shaft needs to extend 1-1/2" beyond
the door mount bracket.
• If the operator is mounted below
8ft. (2.5 m), a chain guard must be
installed to protect against possible
injury. See accessories page.
To prevent damage to door and operator:
• ALWAYS disable locks BEFORE installing and operating the operator.
• ONLY operate door operator at 120V, 60 Hz to avoid malfunction and damage.
• DO NOT exceed 10 complete cycles of door operation per hour.
• DO NOT run operator if the door is locked.
• Chain guard to be installed where the drive chain is exposed lower than 8 feet
(2.5m).
To prevent possible SERIOUS INJURY or DEATH:
• ALWAYS call a trained door systems technician if door binds, sticks or is out of
balance. An unbalanced door may NOT reverse when required.
• NEVER try to loosen, move or adjust door, door springs, cables, pulleys, brackets
or their hardware, ALL of which are under EXTREME tension.
• Disable ALL locks and remove ALL ropes connected to door BEFORE installing
and operating door operator to avoid entanglement.
• DO NOT install operator below 6 feet (1.83 m).
SPECIFICATIONS
Volts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .120 Vac - 60 Hz, ONLY
Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5 AMP
Rated Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .385 in. lb./sec. 10 Cycles per Hour
Maximum Door Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 ft.
Maximum Door Size . . . . . . . . . . . . . . . . . . .14 ft. x 12 ft. (not to exceed 168 sq./ft.)

4
Carton Inventory
Introduction
Hardware
Your door operator is packaged in one carton which contains the motor unit and the parts illustrated below. If anything is missing,
carefully check the packing material.
Tubular Spacer 1/2" (6)
Tubular Spacer 2" (3)
Cap Screw 1/4"-20 x 2" (1)
Nylock Lock Nut 1/4"-20 (1)
Hex Head Bolt 3/8"-16 x 4" (3)
Flat Washer 3/8" (3)
Serrated Flange Nut 5/16"-18 (3)
Carriage Bolt 1/4"-20 x 1/2" (2)
Self-Threading Screw #10-32 (8)
Rope (1)
Handle (1)
Wing Nut 1/4"-20 (2)
Hex Drive Round Head Bolt 1/4"-20 x
1/2"(2)
Warning Tag for Release Handle (1)
2-Conductor Bell Wire
White and White/Red
Safety Labels
and
Literature
Mounting Bracket (4)
Door Sprockets
The Protector System®
(2) Safety Reversing Sensors
(1 Sending Sensor and 1 Receiving Sensor)
with 2-Conductor White and White/Black
Bell Wire attached
Safety Reversing Sensor
Bracket (2)
Door Operator
Single Button Control
Station
12 Tooth Drive Sprocket
with Drive Chain
Additional Items You May Need
Extension brackets (Model 041A5281-1)
or wood blocks: Depending upon building
construction, extension brackets or wood
blocks may be needed to install the safety
reversing sensor.
Fastening hardware: Alternate floor
mounting of the safety reversing sensor
will require hardware not provided.
90˚ connector for cable conduit or flex
cable adapter: Required for permanent
wiring.
Battery Backup (Model 485LM): Provides
backup power to the door operator.

5
The door operator can be installed on
either side of the door.
The drive sprocket can be installed on the
right or left side of the operator depending
on your installation. The drive sprocket can
be mounted in one of three positions to aid
in the alignment of the drive sprocket with
the door sprocket.
1. Insert the drive sprocket into the
motor shaft.
2. Align the center holes in the drive
sprocket with the hole in the motor
shaft.
3. Insert bolts into the motor shaft and
the drive sprocket.
4. Hand tighten the bolts.
The operator can be mounted to the wall
with the mounting brackets provided. An
optional mounting bracket Model 3950MB
is available for purchase, see Accessories
page 30.
1. Position two mounting brackets on
each side of the operator.
2. Fasten the mounting brackets to the
operator using the self-threading
screws provided.
Attach the Drive
Sprocket
Attach Mounting
Brackets
Assembly
1
2
Mounting Brackets
Motor
Shaft Drive Sprocket
Bolt
Bolt

6
Installation
IMPORTANT INSTALLATION INSTRUCTIONS
To reduce the risk of SEVERE INJURY or
DEATH:
Identify the door type for your installation and review the requirements before beginning
installation.
LIVE SHAFT DOOR
The axle rotates with the drum and door assembly when the door is opened or closed.
DEAD SHAFT DOOR
The axle is locked in place while the door opens and closes.
Introduction
Rotating Shaft Fixed Shaft
LIVE SHAFT DOOR DEAD SHAFT DOOR
1. READ AND FOLLOW ALL INSTALLATION WARNINGS
AND INSTRUCTIONS.
2. Install door operator ONLY on properly balanced and
lubricated door. An improperly balanced door may
NOT reverse when required and could result in SEVERE
INJURY or DEATH.
3. ALL repairs to cables, spring assemblies and other
hardware MUST be made by a trained door systems
technician BEFORE installing operator.
4. Disable ALL locks and remove ALL ropes connected to
door BEFORE installing operator to avoid entanglement.
5. If the operator must be installed less than 2.44m (8ft.)
above the floor, then exposed moving parts must
be protected by covers or guarding, provided by the
operator manufacturer.
6. Mount the emergency release within reach, but at least
6feet (1.83 m) above the floor and avoiding contact
with vehicles to avoid accidental release.
7. NEVER connect door operator to power source until
instructed to do so.
8. NEVER wear watches, rings or loose clothing while
installing or servicing operator. They could be caught in
door or operator mechanisms.
9. Install wall-mounted door control:
• within sight of the door.
• out of reach of small children at a minimum height
of 5 feet (1.5 m) above floors, landings, steps or
any other adjacent walking surface.
• away from ALL moving parts of the door.
10. Install the Emergency Release Marking. Attach the
marking on or next to the emergency release. Install the
Entrapment Warning Placard next to the door control in
a prominent location.
11. Place emergency release/safety reverse test label in plain
view on inside of door.
12. Upon completion of installation, test safety reversal
system. Door MUST reverse on contact with a 1-1/2"
(3.8 cm) high object (or a 2x4 laid flat) on the floor.

7
For live shaft door installations the door sprocket is attached to the door axle which spins
the drums and rolls the door curtain.
MINIMUM SIDE CLEARANCE
A minimum of 11" (27.9 cm) clearance on the outside of the door opening is required
for standard wall mounting or outside mounting using the optional mounting bracket
Model3950MB.
A minimum of 3.75" (9.5 cm) clearance on the outside of the door opening is required for
inside mounting using the optional mounting bracket Model 3950MB.
MINIMUM SHAFT LENGTH
The door shaft must extend past the drum bracket a minimum of 1.5" (3.8 cm) (2.5"
[6.3cm] recommended) for installing the door sprocket.
Live Shaft Door Requirements
Installation
2.5" (6.3 cm)
Door Shaft
Door Guide
Drum Bracket
Drum Door
11" (27.9 cm) Min. Clearance
Outside Mounting
3.75" (9.5 cm) Min. Clearance
Inside Mounting

8
Installation
For dead shaft door installations the door sprocket is attached to the door drum which
spins to move the door.
DRUM CONDITON
The door drum must not be bent or damaged. If bent, the drive chain may not align to the
sprocket and could derail the chain.
If the drum does not have mounting holes which align to the door sprocket, use the door
sprocket as a template to drill holes in the proper location.
SPRING CLEARANCE
The internal door springs must not interfere with the door sprocket installation. Inspect
for interference by sliding the door sprocket on the door shaft to the drum and aligning
the mounting holes. Sprocket mounting holes should not be obstructed by the door
spring for a minimum depth of 3" (7.6 cm). Some door manufacturers require the door to
be modified with an extra drum on the end of the door barrel to provide an unobstructed
platform for door sprocket installation.
DOOR CLEARANCE
The dead shaft door must not have more than a 2" (5 cm) space from the curtain edge to
the drum. The door operator comes with a selection of spacers that can be used together
to provide a maximum 3" (7.6 cm) of spacing.
MINIMUM SIDE CLEARANCE
A minimum of 11" (27.9 cm) clearance on the outside of the door guide is required for
outside mounting. A minimum of 3.75" (9.5 cm) clearance is required for inside mounting.
If the door brackets interfere with door operator installation, move the door brackets away
from the door assembly to provide room in the desired location.
Dead Shaft Door Requirements
Drum Spring
Door
Shaft
Door
Bracket
Door Guide
2.5" (6.3 cm) Min.
Clearance
11" (27.9 cm) Min. Clearance
Outside Mounting
3.75" (9.5 cm) Min. Clearance
Inside Mounting
3" (7.6 cm)Bolt
Clearance
2" (5 cm) Max Inset
Door Sprocket
Mounting Pattern
Use 3 holes 120˚ Apart
Remove existing door sprocket. You
MUST use the door sprocket provided in
order for the door operator to function
correctly.

9
Remove existing door sprocket. You MUST use the door sprocket provided in order for
the door operator to function correctly.
The instructions below describe the general installation procedure. Refer to the door
manufacturer for specific instructions regarding your door.
LIVE SHAFT
1. Slide the door sprocket onto the end of the door shaft.
2. Mark and drill a hole through the door shaft.
3. Attach the door sprocket to the door shaft with the through bolt and nylock nut.
DEAD SHAFT
1. Slide the door sprocket onto the end of the door shaft.
2. Attach the door sprocket to the door drum with the through bolts, flat washers,
tubular spacers, and flange nuts.
Install the Door Sprocket
1
Installation
Door
Sprocket
Door
Door Shaft
Door Sprocket
Through
Bolt
Nylock
Nut
Door Sprocket
Drum
Door Sprocket
Tubular Spacer
Flat Washer
Drum
Flange Nut

10
Installation
Mount the Door Operator
2
MOUNTING OPTIONS
There are three options for mounting the door operator:
• Standard wall mount using the brackets included with the door operator.
• Outside bracket mount using the optional mounting bracket Model 3950MB.
• Inside bracket mount using the optional mounting bracket Model 3950MB.
Anchors must be fastened to structural members only. Use concrete anchors for masonry
construction.
NOTE: Mounting the operator to drywall is not recommended.
To prevent possible SERIOUS INJURY
or DEATH:
• Concrete anchors MUST be used if
mounting bracket into masonry.
• NEVER try to loosen, move or
adjust door, springs, cables,
pulleys, brackets or their hardware,
ALL of which are under EXTREME
tension.
• ALWAYS call an authorized service
technician if door binds, sticks or is
out of balance. An unbalanced door
might NOT reverse when required.
• Operator MUST be mounted at a
right angle to the door shaft.
Drive sprocket inner position
1" (2.5 cm) from door guide
Drive sprocket inner position
1" (2.5 cm) from door guide
Drive sprocket outer position
1-5/8" (4.1 cm) from door guide
Drive sprocket middle position
5/8" (1.6 cm) from door guide
Mounting
brackets
Drive sprocket middle position
1-3/8" (3.5 cm) from door guide
OUTSIDE MOUNT WITH OPTIONAL 3950MB MOUNTING BRACKET
STANDARD MOUNTING WITH BRACKETS PROVIDED
INSIDE MOUNT WITH OPTIONAL 3950MB MOUNTING BRACKET
Door Guide
Door Guide

11
Installation
Mount the Door Operator (continued)
2
MOUNT THE DOOR OPERATOR AND ATTACH THE CHAIN
1. Raise the door operator to approximate mounting position. Align the drive sprocket
with the door sprocket.
NOTE: The drive sprocket can be mounted in one of three positions to aid in the
alignment of the drive sprocket with the door sprocket.
2. Wrap the chain around the door sprocket and drive sprocket.
3. Connect the ends of the chain using the master link.
4. Raise or lower the door operator until the chain is taut but not tight. Make sure the
door operator motor shaft is parallel to the door shaft.
5. Fasten the operator to the mounting surface with the appropriate hardware
(notprovided).
6. Tighten the drive sprocket bolts using a 5/32" Allen wrench.
Chain
Chain
Mounting Hardware
(not provided)
DEAD SHAFT DOORLIVE SHAFT DOOR
Mounting Hardware
(not provided)
Tighten drive
sprocket
If the operator is mounted below 8ft.
(2.5 m), chain guard model 3950CGJ must
be installed to protect against possible
injury, see accessories page 30.

12
Attach the Emergency
Release Rope and
Handle
Install the Single
Button Control Station
3
4
1. Insert one end of the emergency
release rope through the handle.
Make sure that “NOTICE” is right side
up. Secure with an overhand knot at
least 1" (2.5 cm) from the end of the
rope to prevent slipping.
2. Insert the other end of the emergency
release rope through the hole in
the trolley release arm. Mount the
emergency release within reach, but
at least 6 feet (1.83 m) above floor,
avoiding contact with vehicles to
prevent accidental release and secure
with an overhand knot.
NOTE: If it is necessary to cut the rope,
heat seal the cut end with a match or
lighter to prevent unraveling.
Installation
Door Operator
Emergency Release Cable
Overhand Knot
Overhand Knot
Emergency Release Handle
To prevent possible SERIOUS INJURY or DEATH from a falling door:
• If possible, use emergency release handle to disengage door ONLY when door
is CLOSED. Weak or broken springs or unbalanced door could result in an open
door falling rapidly and/or unexpectedly.
• NEVER use emergency release handle unless doorway is clear of persons and
obstructions.
To prevent possible SERIOUS INJURY or DEATH from electrocution:
• Be sure power is NOT connected BEFORE installing door control.
• Connect ONLY to 24VOLT low voltage wires.
To prevent possible SERIOUS INJURY or DEATH from a closing door:
• Install door control within sight of commercial door, out of reach of small children
at a minimum height of 5 feet (1.5 m) above floors, landings, steps or any other
adjacent walking surface, and away from ALL moving parts of door.
• NEVER permit children to operate or play with door control push buttons or
remote controls.
• Activate door ONLY when it can be seen clearly, is properly adjusted and there are
no obstructions to door travel.
• ALWAYS keep door in sight until completely closed. NEVER permit anyone to
cross path of closing door.
132A2112-2
DO NOT EXCEED 10 DOOR OPERATIONS
PER HOUR.
FASTEN LABEL ADJACENT TO DOOR.
NE PAS FAIRE FONCTIONNER LA PORTE
PLUS DE 10 FOIS PAR HEURE.
FIXER L’ÉTIQUETTE PRÈS DE LA
PORTE.
Red White WHT
To insert or release wire, push
in tab with screwdriver tip
Single Button
Control Station
WHT/RED
Install the door control within sight of
the door at a minimum height of 5 ft.
(1.5m) where small children cannot
reach, and away from the moving parts
of the door.
1. Remove the control station cover.
2. Fasten the control station to the wall
at least 5' (1.5 m) above the ground.
The installation surface must be
smooth and flat.
3. Select appropriate knockout and run
the wires to the operator.
4. Connect wires to the control station
and replace the control station cover.
5. Fasten the warning placards to the
wall next to the single button control
station.
NOTE: DO NOT connect the power and
operate the door operator at this time. The
door will travel to the full open position but
will not return to the close position until the
safety reversing sensors are connected and
properly aligned. See page 13.

13
The safety reversing sensor must be connected and aligned correctly before the door
operator will move in the down direction. This is a required safety device and cannot
be disabled. The LiftMaster Light Curtain LC36A may be installed as an optional
secondary safety device, see page16.
IMPORTANT INFORMATION ABOUT THE SAFETY REVERSING SENSORS
When properly connected and aligned, the safety reversing sensor will detect an obstacle
in the path of its electronic beam. The sending sensor (with an amber indicator light)
transmits an invisible light beam to the receiving sensor (with a green indicator light).
If an obstruction breaks the light beam while the door is closing, the door will stop and
reverse to full open position.
The sensors must be installed inside the building so that the sending and receiving eyes
face each other across the door, no more than 6" (15 cm) above the floor. Either can be
installed on the left or right of the door as long as the sun never shines directly into the
receiving sensor lens.
If it is necessary to mount the units on the wall, the brackets must be securely fastened
to a solid surface such as the wall framing. Extension brackets (see accessories) are
available if needed. If installing in masonry construction, add a piece of wood at each
location to avoid drilling extra holes in masonry if repositioning is necessary.
The invisible light beam path must be unobstructed. No part of the door (door tracks,
springs, hinges, rollers or other hardware) may interrupt the beam while the door is
closing.
Install The Protector System
5
Installation
Be sure power is NOT connected to the
door operator BEFORE installing the
safety reversing sensor.
To prevent SERIOUS INJURY or
DEATH from a closing door:
• Correctly connect and align the
safety reversing sensor. This
required safety device MUST NOT
be disabled.
• Install the safety reversing sensor
so beam is NO HIGHER than 6"
(15cm) above floor.
Invisible Light Beam
Protection Area
Safety Reversing Sensor
6" (15 cm) max. above floor Safety Reversing Sensor
6" (15 cm) max. above floor
Facing the door from inside the building.

14
Installation
INSTALLING THE BRACKETS
Be sure power to the operator is disconnected. Install and align the brackets so the safety reversing sensors will face each other across
the door, with the beam no higher than 6" (15 cm) above the floor. They may be installed in one of three ways, as follows.
OPTION B: FLOOR INSTALLATION
1. Use wood blocks or extension
brackets (see Accessories) to elevate
sensor brackets so the lenses will be
no higher than 6" (15 cm) above the
floor.
2. Carefully measure and place right and
left assemblies at the same distance
out from the wall. Be sure all door
hardware obstructions are cleared.
3. Fasten to the floor with concrete
anchors as shown.
Fasten Wood Block to Wall with
Lag Screws (not provided)
Attach with Concrete Anchors
(not provided)
OPTION A: WALL INSTALLATION
1. Place the bracket against the wall
with curved arms facing the door. Be
sure there is enough clearance for the
sensor beam to be unobstructed.
2. If additional depth is needed, an
extension bracket (see Accessories)
or wood blocks can be used.
3. Use bracket mounting holes as a
template to locate and drill (2) 3/16"
diameter pilot holes on the wall at
each side of the door, no higher than
6" (15 cm) above the floor.
4. Attach brackets to wall with
lagscrews (notprovided).
If using extension brackets or wood blocks,
adjust right and left assemblies to the same
distance out from the mounting surface.
Make sure all door hardware obstructions
are cleared.
Safety Reversing Sensor Bracket
Lag Screws (not provided)
Safety Reversing Sensor Bracket
(Provided with Extension Bracket)
Extension Bracket (See Accessories)
Safety Reversing Sensor
Bracket
(Provided with
Extension Bracket)

15
Installation
WIRE THE SAFETY REVERSING SENSORS
1. Run the wire from both sensors to the door operator. Attach the wire to the wall and
ceiling with the staples.
2. Strip 7/16" (11 mm) of insulation from each set of wires. Separate the wires. Twist
the white wires together. Twist the white/black wires together.
3. Insert the white wires into the white terminal on the door operator. Insert the white/
black wires into the grey terminal on the door operator. To insert or remove the
wires from the terminal, push in the tab with a screwdriver tip.
MOUNTING THE SAFETY REVERSING SENSORS
1. Slide a 1/4"-20x1/2" carriage bolt head into the slot on each sensor.
2. Use wing nuts to fasten safety reversing sensors to brackets, with lenses pointing
toward each other across the door. Be sure the lens is not obstructed by a bracket
extension.
3. Finger tighten the wing nuts.
HARDWARE
Wing Nut
1/4"-20 (2)
Carriage Bolt
1/4"-20x1/2" (2)
WHT/
BLK
WHT
Bell wire
7/16"
(11mm)
Carriage Bolt
Wing Nut

16
Installation
Install the Light Curtain (Not Provided)
6
The following are general instructions for a typical installation, refer to the
complete instructions included with the Light Curtain.
The plug-in power supply accessory (model 100MAPS) is required to power the
Light Curtain. LiftMaster Light Curtain (Model LC-36A) is an ancillary entrapment
protection device designed with 8 optical sensors that form 22 total invisible light
beams which create a cross-pattern or netting effect for maximum protection against
entrapment. If an obstruction breaks any light beam while the door is closing, the
operator will stop and reverse to the full open position. The Light Curtain Transmitter
must be installed facing the Light Curtain Receiver across the entrapment zone, 12"
(30.5 cm) above the primary monitored entrapment protection device. The minimum
installation width is 3 ft. (.91 m) and the maximum width is 33 ft. (10 m).
NOTE: Ensure that no part of the door, door tracks, springs, hinges, rollers, cords or
other hardware interrupts the light beam while the door is closing.
INSTALLATION
1. Fasten the mounting brackets loosely to both Light Curtains with the screws
provided.
2. Measure a minimum of 12" (30.5 cm) above the safety reversing sensors. Mark
this location. The Light Curtain must be installed above this point.
3. Hold the Light Curtain up to the desired mounting location with the cable end
pointing upward. Secure the bottom mounting bracket to the mounting surface.
The mounting brackets must be securely fastened to a solid surface such as a
wall framing.
4. Make sure the Light Curtain is level and secure the upper mounting bracket to
the mounting surface.
5. Tighten the screws to secure the Light Curtain to the mounting bracket.
6. Secure the other Light Curtain to the opposite side of the door following
steps2- 5, making sure they are aligned.
WIRING
Transmitting Light Curtain:
• White Wire to white terminal on door operator
• Black Wire to grey terminal on door operator
Transmitting and Receiving Light Curtains:
• Brown Wire (+) to White/Black on power supply
• Blue Wire (-) to Black on power supply
To prevent possible SERIOUS INJURY or
DEATH from a closing door:
• Be sure to DISCONNECT POWER to
the operator BEFORE installing the
Light Curtain.
• The door MUST be in the fully opened
or closed position BEFORE installing
the Light Curtain.
• Correctly connect and align the Light
Curtain transmitter and receiver.
• The Light Curtain is for use with
LiftMaster Commercial Doors. Use
with ANY other product voids the
warranty.
• DO NOT use this product for the
protection of dangerous machinery
or in explosive atmospheres or
radioactive environments. Use ONLY
specific and approved types of devices
for such applications.
• The Light Curtain MUST be installed
ONLY by authorized and fully trained
personnel.
• LiftMaster Monitored Entrapment
Protection devices are required in
addition to the Light Curtain. The Light
Curtain may NOT be used as the sole
entrapment protection device for ANY
entrapment zone.
Black
White
12" (30.5 cm) minimum above
the safety reversing sensor
Brown (+)
Blue (-) Black
Black/White
Plug-In Power
Supply
Transmitting Light
Curtain Receiving Light
Curtain
Light
Curtain
Nylon
nut
Mounting
bracket
Screw with
nylon washer

17
Connect Power
7
Installation
To avoid installation difficulties, do not
run the door operator at this time.
To reduce the risk of electric shock, your
door operator has a grounding type plug
with a third grounding pin. This plug will
only fit into a grounding type outlet. If the
plug doesn’t fit into the outlet you have,
contact a qualified electrician to install the
proper outlet.
There are two options for connecting
power:
OPTION A: TYPICAL WIRING
1. Plug in the door operator into a
grounded outlet.
2. DO NOT run door operator at this
time.
To prevent possible SERIOUS INJURY or DEATH from electrocution or fire:
• Be sure power is NOT connected to the operator, and disconnect power to circuit
BEFORE removing cover to establish permanent wiring connection.
• Door installation and wiring MUST be in compliance with ALL local electrical and
building codes.
• NEVER use an extension cord, 2-wire adapter or change plug in ANY way to make it
fit outlet. Be sure the operator is grounded.
RIGHT
WRONG
WRONGRIGHT
Green
Ground
Screw Ground Wire
Black Wire
Wire Nuts
(Not Provided
White Wire
Flexible
Conduit
90˚
Connector
(Not
Provided)
Green Wire White Wire
Black Wire
BACK VIEW
OPTION B: PERMANENT WIRING
CONNECTION
If permanent wiring is required by
your local code, refer to the following
procedure.
To make a permanent connection through
the 7/8" hole in the back of the door
operator (according to local code):
1. Be sure power is NOT connected to
the door operator, and disconnect
power to circuit.
2. Remove the door operator from the
torsion bar, remove cover screws and
set the cover aside.
3. Cut the line cord 6" (15.2 cm) above
the strain relief.
4. Squeeze the strain relief and push
into motor unit, then remove the
strain relief from the line cord.
5. Install a 90° conduit (not provided)
or flex cable adapter (not provided) to
the 7/8" hole. Reinstall door operator
to torsion bar.
6. Run wires through conduit, cut to
proper length and strip insulation.
7. Strip 1/2" (1.3 cm) of insulation from
the existing black, white and green
wires.
8. Connect the line to the black wire and
neutral to the white wire with wire
nuts (not provided). Connect ground
wire to the green ground screw.
9. Properly secure wires under plastic
ties so that they do not come into
contact with moving parts.
10. Reinstall cover.

18
Receiving Sensor
Green LED
Sending Sensor
Amber LED
Installation
IF THE AMBER LED ON THE SENDING SENSOR IS NOT GLOWING:
• Make sure there is power to the door operator.
• Make sure the sensor wire is not shorted/broken.
• Make sure the sensor has been wired correctly: white wires to white terminal and
white/black wires to grey terminal.
If the receiving sensor is in direct
sunlight, switch it with sending
sensor so it is on the opposite side
of the door.
(Invisible light beam)
ENSURE THE SAFETY REVERSING SENSORS ARE ALIGNED
The door will not close if the sensors have not been installed and aligned correctly.
When the light beam is obstructed or misaligned while the door is closing, the door
will reverse. If the door is already open, it will not close. The sensors can be aligned by
loosening the wing nuts, aligning the sensors, and tightening the wing nuts.
1. Check to make sure the LEDs in both sensors are glowing steadily. The LEDs in both
sensors will glow steadily if they are aligned and wired correctly.
WHITE
GREY
IF THE GREEN LED ON THE RECEIVING SENSOR IS NOT GLOWING:
• Make sure the sensor wire is not shorted/broken.
• Make sure the sensors are aligned.

19
Install the Battery Backup (Not Provided)
8
Installation
To reduce the risk of FIRE or INJURY
to persons:
• Disconnect ALL electric and battery
power BEFORE performing ANY
service or maintenance.
• Use ONLY LiftMaster part # 485LM
for replacement battery.
• DO NOT dispose of battery in fire.
Battery may explode. Check with local
codes for disposal instructions.
ALWAYS wear protective gloves and
eye protection when changing the
battery or working around the battery
compartment.
When in Battery Backup mode, MyQ®Smartphone Control and wireless MyQ devices
will be disabled.
1. Unplug the door operator.
2. Use a Phillips head screwdriver to remove the battery cover on the door operator.
3. Partially insert the battery into the battery compartment with the terminals facing
out.
4. Connect red (+) and black (-) wires from the door operator to the corresponding
terminals on the battery.
5. Replace the battery cover.
6. Plug in the door operator.
BATTERY STATUS LED
Green LED:
All systems are normal.
• A solid green LED light indicates the battery is fully charged.
• A flashing green LED indicates the battery is being charged.
Orange LED:
The door operator has lost power and is in battery backup mode.
• A solid orange LED with beep, sounding approximately every 2 seconds, indicates
the door operator is operating on battery power.
• A flashing orange LED with beep, sounding every 30 seconds, indicates the battery
is low.
Red LED:
The door operator's 12V battery needs to be replaced.
• A solid red LED with beep, sounding every 30 seconds, indicates the 12V battery will
no longer hold a charge and needs to be replaced. Replace the battery back up to
maintain the battery backup feature.
NOTE: Battery does not have to be fully charged to activate the door operator.
Red wire (+)
Battery Status LED
Black wire (-)

20
Travel limits regulate the points at which the door will stop when moving up or down.
Program the Travel Limits
Adjustments
Without a properly installed safety
reversal system, persons (particularly
small children) could be SERIOUSLY
INJURED or KILLED by a closing door.
• Incorrect adjustment of door travel
limits will interfere with proper
operation of safety reversal system.
• After ANY adjustments are made,
the safety reversal system MUST
be tested. Door MUST reverse on
contact with 1-1/2" high (3.8 cm)
object (or 2x4 laid flat) on floor.
To prevent damage to vehicles, be
sure fully open door provides adequate
clearance.
1
While programming, the UP and DOWN buttons can be used to move the door as needed.
1. Press and hold the Adjustment Button until the UP Button begins to flash and/or a
beep is heard.
2. Press and hold the UP Button until the door is in the desired UP position.
3. Once the door is in the desired UP position press and release the Adjustment Button.
The door operator will beep and the DOWN button will flash.
4. Press and hold the DOWN Button until the door is in the desired DOWN position.
5. Once the door is in the desired DOWN position press and release the Adjustment
Button. The door operator will beep and the UP button will flash.
6. Press and release the UP Button. When the door travels to the programmed UP
position, the DOWN Button will begin to flash.
7. Press and release the DOWN Button. The door will travel to the programmed DOWN
position. Programming is complete.
If you are unable to program the travel:
• Check to see if the safety reversing sensors are misaligned or obstructed (refer to
page 18). When the sensors are aligned and unobstructed, cycle the door through
a complete up and down cycle using the remote control or the UP and DOWN
buttons. If you are unable to operate the door up and down, repeat the steps for
above.
1 2 3
5
4
6 7
PROGRAMMING BUTTONS
UP Button
Adjustment
Button
DOWN Button