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