Chamberlain Liftmaster Security+ 3900PLD User manual

Owner’s Manual
■Please read this manual and the enclosed safety materials carefully!
■Fasten the manual near the door after installation.
■The door WILL NOT CLOSE unless The Protector System®and cable tension monitor are
connected and properly aligned.
■Periodic checks of the operator are required to ensure safe operation.
■The model number label is located behind the hinged door of your operator.
■Do NOT exceed 10 complete cycles of door operation per hour.
DOOR OPERATOR
Model 3900PLD
For Light Duty Commercial Use Install On
Sectional Doors With Torsion Assemblies Only
The Chamberlain Group, Inc.
845 Larch Avenue
Elmhurst, Illinois 60126-1196
www.liftmaster.com
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Serial #
Installation Date
2 YEAR WARRANTY

2
INTRODUCTION
Safety Symbol Review
and Signal Word Review
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 garage
door and/or the garage door operator if you do not comply
with the cautionary statements that accompany it. Read
them carefully.
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.
Mechanical
Electrical
Introduction 2-5
Safety symbol review and signal word review . . . . . . . . . . 2
Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Preparing your door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Tools needed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Carton inventory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Hardware inventory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Assembly 6
Attach the collar to the operator. . . . . . . . . . . . . . . . . . . . . 6
Attach mounting bracket to the operator . . . . . . . . . . . . . . 6
Installation 7-16
Installation safety instructions . . . . . . . . . . . . . . . . . . . . . . 7
Position the operator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Attach the emergency release rope and handle . . . . . . . . 8
Install power door lock (Not Provided) . . . . . . . . . . . . . . . . 8
Attach the cable tension monitor (Required) . . . . . . . . . . . 9
Install the single button control station. . . . . . . . . . . . . . . 10
Install the light (Not Provided) . . . . . . . . . . . . . . . . . . . . . 11
Electrical requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Mount the Standby Power Unit (SPU) (Not Provided) . . . 13
Install The Protector System®. . . . . . . . . . . . . . . . . . . 14-16
Adjustment 17-20
Program the travel limits . . . . . . . . . . . . . . . . . . . . . . . . . 17
Set the force. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Test the safety reversal system . . . . . . . . . . . . . . . . . . . . 19
Test The Protector System®. . . . . . . . . . . . . . . . . . . . . . . 19
Test cable tension monitor . . . . . . . . . . . . . . . . . . . . . . . . 20
To open door manually . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Operation 21-25
Operation safety instructions . . . . . . . . . . . . . . . . . . . . . . 21
Using your door operator . . . . . . . . . . . . . . . . . . . . . . . . . 21
Care of your operator . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Having a problem? (Troubleshooting) . . . . . . . . . . . . 23-24
Diagnostic Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Programming 26-28
To add or reprogram a hand-held
remote control (Not Provided) . . . . . . . . . . . . . . . . . . . . . 26
To erase all codes from motor unit memory . . . . . . . . . . 26
3-Button remote . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
The remote control battery . . . . . . . . . . . . . . . . . . . . . . . . 26
To add, program or change a keyless entry
PIN (Not Provided) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Programming remote light (Not Provided) . . . . . . . . . . . . 28
Repair Parts 29
Installation parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Motor unit assembly parts . . . . . . . . . . . . . . . . . . . . . . . . 29
Accessories 30
Notes 31
Repair Parts and Service 32
TABLE OF CONTENTS

Safety
Reversing Sensor
Safety
Reversing
Sensor
Torsion Spring
Motor unit
Wall-mounted Single
Button Control Station
Access Door
Gap between floor
and bottom of door must not exceed 1/4" (6 mm).
Cable Tension
Monitor
Drum
3
Planning
Survey your area to see if any of the conditions below
apply to your installation. Additional materials may be
required. You may find it helpful to refer back to this page
as you proceed with the installation of your operator.
Depending on your requirements, there are several
installation steps which may call for materials or hardware
not included in the carton.
This operator is compatible with:
•Doors that use a torsion bar, springs and a door no
more than 14' (4.2 m) high.
•4"-6" (10 cm - 15 cm) drums, not to be used on tapered
drums over 6" (15 cm).
•High lift and standard lift sectional doors up to 14'
(4.2 m) high.
•Doors up to 18' (5.4 m) wide.
•Doors up to 180 sq. ft. (16.7 sq. m).
•1" (2.5 cm) torsion bar only.
•Review or inspect proposed installation area. Operator
can be installed on left or right side of door. Select the
side that meets the requirements listed below.
- Must have minimum of 2-1/2" (6.4 cm) between the
wall and the center of the torsion bar.
- Must have minimum of 3" (7.6 cm) between the ceiling
and the center of torsion bar.
- Must have minimum of 8" (20.3 cm) between the side
wall (or obstruction) and the end of torsion bar.
•The torsion bar must extend at least 1" to 5"
(2.5 cm to 12 cm) past the bearing plate.
•An electric outlet is required within 6' (1.8 m) of the
installation area. If outlet does not exist, contact a
qualified electrician.
•Depending upon building construction, extension
brackets or wood blocks may be needed to install safety
reversing sensors.
•Alternate floor mounting of the safety reversing sensors
will require hardware not provided.
•A model 475LM EverChargeTM Standby Power Unit is
strongly recommended if there is no access door to the
garage, as this operator cannot be used in conjunction
with an external emergency release mechanism.
•Any gap between the floor and the bottom of the door
must not exceed 1/4" (6 mm). Otherwise the safety
reversal system may not work properly.
NOTE: Inspect the torsion bar while the door is raised and
lowered. It is important that there is no noticeable
movement up and down or left and right. If this type of
movement is not corrected, life of this operator will be
greatly reduced.

4
Preparing your Door
Before you begin:
•Disable locks.
•Remove any ropes connected to door.
•Complete the following test to make sure your door is
balanced and is not sticking or binding:
1. Lift the door about halfway as shown. Release the
door. If balanced, it should stay in place, supported
entirely by its springs.
2. Raise and lower the door to see if there is any
binding or sticking.
If your door binds, sticks or is out of balance, call a
trained door systems technician.
3. Verify equal cable tension on each side of door.
Cable tension should remain equal during the entire
travel of the door. 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.
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.
Tools needed
During assembly, installation and adjustment of the
operator, instructions will call for hand tools as illustrated
below.
Pliers Wire Cutters
Claw Hammer
Screwdriver
Adjustable End Wrench
1/4", 5/16" & 3/8" Sockets
and Wrench with 6" Extension
Drill Tape Measure
2
1
Stepladder
Pencil
3/16" and 1/8"
Hex Key Wrench
Needle Nose Pliers
5/32", 3/16", 5/16"
and 3/4" Drill Bits
Sectional Door
Torque Meter (not shown)
Specifications
Volts . . . . . . . . . . . . . . . . . . . 120Vac - 60 Hz, ONLY
Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 AMP
Rated Load. . . . . . . . . . . . . . . . . 325 in.lb/sec
10 Cycles per Hour

5
2-Conductor Bell Wire
White & White/Red
Safety Labels
and
Literature
Mounting Bracket
The Protector System®
(2) Safety Reversing Sensors
(1 Sending Eye and 1 Receiving Eye)
with 2-Conductor White & White/Black
Bell Wire attached
Safety Sensor
Bracket (2)
Operator
Collar with Screws
Cable Tension
Monitor with 2-Conductor
Green/White Bell Wires
Single Button Control Station
Carton Inventory
Your door operator is packaged in one carton which
contains the motor unit and the parts illustrated below.
Note that accessories will depend on the model
purchased. If anything is missing, carefully check the
packing material.
Hardware Inventory
INSTALLATION HARDWARE
Hex Screw #14-10x1-7/8" (4)
Screw #6x-1-1/4" (2)
Machine Screw #6x1" (2)
Carriage Bolt 1/4"-20x1/2" (2)
Wing Nut 1/4"-20 (2)
Pan Head Screw 1/4"-20x1/2" (2)
Hex Head Screw #8x1" (2)
Self Tapping Screw #10-32 (2)
Drywall Anchor (2)
Drywall Anchor (Screw-In) (2)
Handle
Rope
Insulated Staples (30)

ASSEMBLY STEP 1
Attach the Collar to the Operator
To avoid installation difficulties, do not run the door
operator until instructed to do so.
•Loosen the collar screws.
•Attach collar to either the left or the right side of the
operator. Ensure that the collar is seated all the way on
motor shaft until stop is reached (Figure 1).
•Position the collar so that the screws are facing up
(accessible when attached to the torsion bar).
•Tighten both sides of collar screws equally to secure
collar to the motor unit (12-14 ft./lbs. of torque)
(Figure 2).
NOTE: For most installations the screws should be facing
up for easy access. Do not tighten set screws until
indicated.
6
Collar Screw
Collar Screw
Set Screw
ASSEMBLY STEP 2
Attach Mounting Bracket
to the Operator
•Loosely attach slotted side of mounting bracket to the
same side of the operator as the collar, using
self-threading screws provided.
NOTE: Do not tighten until instructed. Illustrations shown
are for left side installation.
Socket Wrench
Figure 1
RIGHT WRONG
Figure 2
Screw
#10-32
HARDWARE SHOWN ACTUAL SIZE
To prevent possible SERIOUS INJURY or DEATH, the collar
MUST be properly tightened. The door may not reverse
correctly or limits may be lost due to collar slip.

7
INSTALLATION
INSTALLATION STEP 1
Position the Operator
NOTE: For additional mounting options see
accessories page.
1. Close the door completely.
2. Slide the operator with collar over the end of the torsion
bar. Ensure that the collar does not touch the bearing
plate. Check to make sure the mounting bracket is
located on a solid surface such as wood, concrete or
door/flag bracket. Snug collar screws to help assure
proper alignment of operator. Mark the bracket holes. It
may be necessary to cut the torsion bar if it is too long
or damaged.
3. Loosen collar screws from torsion bar and remove the
operator. Drill 3/16" pilot holes at the marked locations.
Drill through steel plate if needed.
4. Reinstall the operator by sliding the collar over the
torsion bar until pilot holes align with bracket. Securely
tighten collar screws that attach to the torsion bar to
12-14 ft./lbs. of torque. Securely tighten both set screws
firmly, without damaging the motor unit.
5. Fasten bracket securely with 14-10x1-7/8" screws.
Tighten all mounting bracket hardware.
NOTE: The motor unit does not have to be flush to wall.
6. Use a staple to secure the antenna wire to prevent
antenna from being entangled in a door roller.
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 a trained door systems 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 torsion
bar to avoid premature wear on the collar.
Operator
Staple
Torsion Bar
14-10x1-7/8" Hex Screw
HARDWARE SHOWN ACTUAL SIZE
IMPORTANT INSTALLATION INSTRUCTIONS
To reduce the risk of SEVERE INJURY or DEATH:
WARNING
WARNING
WARNINGWARNING
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 Mount emergency release handle no higher than 6 feet
(1.83 m) above floor.
6. NEVER connect door operator to power source until
instructed to do so.
7. NEVER wear watches, rings or loose clothing while installing
or servicing operator. They could be caught in door or
operator mechanisms.
8. Install wall-mounted door control:
• within sight of the door.
• out of reach of children at minimum height of 5 feet
(1.5 m).
• away from ALL moving parts of the door.
9. Install the entrapment warning placard next to the control
station in a prominent location.
10. Place manual release/safety reverse test label in plain view
on inside of door.
11. 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.

NOTICE
Overhand
Knot
Emergency
Release Handle
Overhand
Knot
Rope
Motor Unit
Emergency
Release Cable
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.
INSTALLATION STEP 2
Attach the Emergency Release Rope
and Handle
•Thread one end of the rope through the hole in the top
of the red handle so “NOTICE” reads right side up as
shown. Secure with an overhand knot at least 1"
(2.5 cm) from the end of the rope to prevent slipping.
•Thread the other end of the rope through the loop in the
emergency release cable.
•Adjust rope length so the handle is no higher than 6'
(1.83 m) above the floor. 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.
8
Staples
Lock Screw
1/4-20 x 1/2" (2)
HARDWARE SHOWN ACTUAL SIZE
INSTALLATION STEP 3
Install Power Door Lock
(Not Provided)
The lock is used to prevent the door from being
manually opened once the door is fully closed.
1. Select a door roller to mount the lock above. Check
for clearance. If possible select a roller on the same
side of the door as the motor unit.
The second roller up from the bottom is ideal in
most installations.
2. Ensure rail surface is clean and adhere lock
template to achieve a 3" (7.6 cm) distance between
the center of the roller and the pin hole (Figure 1).
3. Drill holes as marked on the template.
4. Fasten power door lock to the outside of the garage
door track with hardware provided.
5. Run bell wire up wall to motor unit. Use insulated
staples to secure wire in several places.
6. Plug connector into the motor unit (Figure 2).
NOTE: Lock must be mounted within 10' of the
power head.
Lock Template
Roller
Garage
Door Track
TOP
DRILL 5/16"
DRILL 3/4"
DRILL 5/16"
132A2505
Approx. 3"
(7.6 cm)
TOP
DRILL5/16"
DRILL3/4"
DRILL5/16"
132A2505
Door Track
Figure 2
Figure 1

WHT/GRN
To insert or release wire,
push in tab with
screwdriver tip
Cable Tension
Monitor
7/16" (11mm)
Strip wire 7/16" (11mm)
WHT/GRN
Cable
Tension
Monitor
Cable Tension
Monitor Roller
Cable
2"-6"
(5 cm-
15 cm)
Drum
Torsion Bar
Operator
1/8"-1/4"
(3 mm-6 mm)
With Door Closed
Preferred Orientation
Figure 1
#8 Hex Head Screw (2)
Screw #6 (2) Wall Anchor (2)
Staples
HARDWARE SHOWN ACTUAL SIZE
Figure 3
INSTALLATION STEP 4
Attach the Cable Tension Monitor
(Required)
This operator comes standard with the cable tension
monitor. It is supplied as a device to monitor the
cables for ANY slack that may occur and will reverse
the door when excessive slack is detected, eliminating
service calls.
The cable tension monitor MUST be connected and
properly installed before the door operator will move
in the down direction.
NOTE: The cable tension monitor is shipped for left side
installation. It is preferred that the cable tension monitor be
installed on the same side of the door as the operator.
If required, it can be mounted on the opposite side of door.
Remove the snap-ring holding the roller in place and
reassemble it on the opposite side of the cable tension
monitor.
1. Position the cable tension monitor as shown
(Figures 1 and 2). The cable tension monitor should be
located as close to the drum as possible.
NOTE: There must be no obstructions in the installation
area that prevent the cable tension monitor or the cable
itself from closing completely when slack is detected.
2. Make sure cable tension monitor is located over a wood
support member.
NOTE: If the cable tension monitor can not be mounted
into wood with the lag screws provided, it can be mounted
into 1/2" or greater drywall using the wall anchors (2) and
the #8 hex head screws (2) provided in the hardware bag.
3. Mark and drill 3/16" pilot holes for screws (pilot holes
are not required for anchors).
4. Attach the cable tension monitor to the wall using the
hardware provided. Make sure that the roller is on top of
the cable.
5. Run bell wire to operator. Use insulated staples to
secure wire in several places.
6. Connect bell wire to the green quick-connect terminals
(polarity is not important) (Figure 3).
NOTE: Cable must have tension through entire travel.
Make sure there is no slack in cable on opposite side of
door during normal operation. If this condition exists,
adjust cables as required.
3/4" Min.
(18 mm Min.)
Wall
Drum
Cable
Figure 2
9

INSTALLATION STEP 5
Install the Single Button
Control Station
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 door, out of reach of children
at a minimum height of 5 feet (1.5 m) 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.
10
WHT/RED
WHT
Door Control
Connections
Single Button Control Station
Factory installed
jumper must be in
place for proper
operation. Operator
will not function
without the jumper.
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.
WARNING
Keep Door in Sight at all Times When Door is Moving
Moving Door Can Cause
Serious Injury or Death
Keep Clear! Door May Move at any Time
Without Prior Warning
Do Not Let Children Operate the Door or Play
in the Door Area
Single Button Control Station
Door Control
Connections
WHT/RED
WHT
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.