Chamberlain LIFTMASTER SL920 User manual

1
OWNER'S MANUAL
MODEL SL920
COMMERCIAL SLIDE GATE OPERATOR
2 YEAR WARRANTY
Serial # _____________________
(located on electrical box cover)
Installation Date:_______________
SL920 GATE OPERATORS ARE FOR USE ON VEHICULAR PASSAGES
ONLY AND NOT INTENDED FOR USE ON PEDESTRIAN PASSAGE GATES.

2
General Information.................................................................................................................3, 4
Features...................................................................................................................................5
Parts Identification...................................................................................................................6, 7
Installation................................................................................................................................8-11
Contents
Master Second...................................................................................................................18
Wiring Diagrams....................................................................................................................19, 20
Fine Tuning............................................................................................................................17
Electrical................................................................................................................................13-16
Alternate Installation..............................................................................................................12
Options..................................................................................................................................22-24
Safety Edge...........................................................................................................................21
Maintenance and Safety........................................................................................................25
Troubleshooting....................................................................................................................26, 27
IMPORTANT SAFETY INSTRUCTIONS
WARNING - To reduce the risk of injury or death:
1) READ AND FOLLOW ALL INSTRUCTIONS
2) Never let children operate or play with gate controls. Keep the remote control away from children.
3) Always keep people and objects away from the gate. NO ONE SHOULD CROSS THE PATH OF THE MOVING GATE.
4) Test the gate operator monthly. The gate MUST reverse on contact with a rigid object or stop when an object activates the non-contact sensors. After
adjusting the force or the limit of travel, retest the gate operator. Failure to adjust and retest the gate operator properly can increase the risk of injury or death.
5) Use the emergency release only when the gate is not moving.
6) KEEP GATES PROPERLY MAINTAINED. Read the owner's manual. Have a qualified service person make repairs to gate hardware.
7) The entrance is for vehicles only. Pedestrians must use separate entrance.
8) SAVE THESE INSTRUCTIONS.
Notes......................................................................................................................................28-31
Pg.

3
General Information
BASE PLATE HOLE PATTERN


OVERALL DIMENSIONS: Height: 21" Length: 12" Width: 17"


SHIPPING WEIGHT: 125 lbs.
zOptions: Steel Mounting Stand: 23 lbs.


POWER REQUIREMENT: Dedicated 115 Volt AC (+/- 10V), 5 AMP Power Circuit


APPLICATIONS:
zMaximum Gate Weight: 500 lbs.
zMaximum Gate Length: 25 ft.
zMaximum Track Grade: 5 % (1 ft. rise over 20 ft. run)
zMaximum Gate Speed: 10"/sec.


INCLUDED WITH OPERATOR:
z30-Feet of # 40 Roller Chain
z2-Master Links # 40
z2-Zinc Plated Chain Bolts
z2-Chain Brackets, Right and Left
z2-U-Bolts, Round (for chain brackets)
z2-U-Bolts, Square (for chain brackets)
z2-Safety Warning Placards
z1-Hex Wrench 5/16"
z1-Instruction Manual
z1-Flexible Conduit End Fitting 1/2"
z4-Sleeve Anchor Bolts (red heads) 3/8" X 3"

4


CIRCUIT BOARD: The SL920 uses the Full Systems Capability circuit board, a powerful control
system. This circuit board operates on 12 ~ 18 Volts and can deliver power to the motor through high
power switching. The limit switch input terminals require the use of normally open type limit switches.
These switches are used to accurately stop the gate operator in the open and closed positions. To
safeguard the operator from damage that could result from limit switch or system protection failure, the
Full Systems Capability circuit board has a built-in maximum run timer which will allow the operator to run
for approximately 300 seconds and then shut off automatically. The Full Systems Capability circuit board
has an adjustable gate sensitivity feature which will stop or reverse the gate if the gate is pushing harder
than normal because of an obstruction.


GATE SENSITIVITY: The SL920 Full Systems Capability circuit board has a built-in system
protection feature which when adjusted properly will deliver only enough power to the motor to overcome
the resistance of the gate. The amount of power that the circuit board will deliver can be adjusted for both
directions of travel to accommodate the various gate weights that the SL920 operator is recommended
for. (See Applications Pg. 3)


Vehicular Gate Operator Classes:
Class I - Residential Vehicular Gate Operator: A vehicular gate operator (or system) intended for use in a home of
one-to four single family dwellings, or a garage or parking area associated therewith.
Class II - Commercial/General Access Vehicular Gate Operator: A vehicular gate operator (or system) intended for
use in a commercial location or building such as a multifamily housing unit (five or more single family
units), hotel, garage, retail store, or other building servicing the general public.
Class III - Industrial/Limited Access Vehicular Gate Operator: A vehicular gate operator (or system) intended for use
in an industrial location or building such as a factory or loading dock area or other locations not intended
to service the general public.
Class IV - Restricted Access Vehicular Gate Operator: A vehicular gate operator (or system) intended for use in a
guarded industrial location or building such as an airport security area or other restricted access location
not servicing the general public, in which unauthorized access is prevented via supervision by security
personnel.
Gate Operator model SL920 is intended for Vehicular Gate Operator Classes I, II, III, and IV.


Gate Inspection:
a) Install the gate operator only when:
1) The operator is appropriate for the construction of the gate and the usage Class of the gate,
2) All openings of a horizontal slide gate are guarded or screened from the bottom of the gate to a minimum
of 4 ft. above the ground to prevent a 2-1/4 " diameter sphere from passing through the openings
anywhere in the gate, and in that portion of the adjacent fence that the gate covers in the open position.
3) All exposed pinch points are eliminated or guarded, and
4) Guarding is supplied for exposed rollers.
b) The operator is intended for installation only on gates used for vehicles. Pedestrians must be supplied with a
separate access opening.
c) The gate must be installed in a location so that enough clearance is supplied between the gate and adjacent
structures then opening and closing to reduce the risk of entrapment.
d) The gate must be properly installed and work freely in both directions prior to the installation of the gate operator.
Do not over-adjust the gate sensitivity to compensate for a damaged gate.
General Information continued...

5
Features


OPERATION
The SL920 Full Systems Capability can operate in a AUTO CLOSE TIMER (TIMER ON) or a
PUSH-TO-OPEN/PUSH-TO-CLOSE (TIMER OFF) mode of operation. In the AUTO CLOSE TIMER
mode of operation the operator is given a command to open the gate and hold it open until the input is
released and until the auto close timer has elapsed at which point the operator will close the gate
automatically. In the PUSH-TO-OPEN/PUSH-TO-CLOSE mode of operation each time a signal is sent to
the operator, it will cause it to do the opposite of what it did before. (i.e., If the gate is closed, it will start
opening, if it is open, it will start closing: If it is closing, it will REVERSE TO OPEN, if it is opening, it will
REVERSE TO CLOSE.)


CONTROLS
The SL920 Full Systems Capability works with the following control devices: Key switches, Push
buttons (separate or intercom), numerical key pads and any peripheral equipment which can supply
normally open or normally closed contacts as well as optional radio transmitters and receiver (specified
by and available from the manufacturer). These contacts can be connected to the operator input terminals
to perform the opening, close, safety, or the stop functions.


AUTO CLOSE TIMER
The operator comes factory preset with the auto close timer turned OFF. The auto close timer will
close the gate automatically after a specific amount of time has elapsed. The amount of time can be
easily adjusted between 0 and 45 seconds by turning a small "pot" located on the right edge of the circuit
board (See page 17). The timer can be disabled or activated by flipping a single switch located on the
top right edge of the circuit board. If the timer will be used it is recommended that some type of
supplementary safety device be installed. If more time is required, there is an extended timer available
from the manufacturer allowing up to 100 additional seconds (See Options).


MANUAL RELEASE SWITCH
This simple on-off switch is built into the operator. In an emergency, EVEN WITH THE POWER
OFF, the gate can be pushed open manually after flipping the switch from Operate to Release. This
switch may also be removed and placed externally from the machine.


GATE SENSITIVITY ADJUSTMENT FOR SYSTEM PROTECTION
The amount of force necessary to stop the gate can be adjusted to conform to the various sizes
and weights of any particular gate. When adjusting the sensitivity, the operator can be given only as much
energy as is necessary to overcome the resistance of the gate. If the gate should strike an obstruction in
either direction, the gate will reverse. If the gate should again strike an obstruction before reaching a limit,
the gate will stop, remain stopped, and will sound an alarm. (See page 17)


MASTER AND SECOND
Some very large entrances may require the use of two gates. If this is the case, the two gates can
be easily automated using the "master and second" configuration. This configuration uses two gates and
two operators in ONE driveway. The operators used are two regular SL920 Full Systems Capability
operators one of which is of standard "right hand operation" and the other which is easily converted to
"left hand operation" by flipping a single switch located at the top of the circuit board (See page 17).

6
Parts Identification

7
Parts Identification continued...
K72-30359 SERVICE KIT
K74-40045 SERVICE KIT
LIMIT/DRIVE SHAFT ASSEMBLY
PCB GUARD AND STANDOFF
ITEM
DESCRIPTION QTY
DESCRIPTION QTY
PART # DESCRIPTION QTY
LIMIT/DRIVE SHAFT 1
GUARD, PCB 1
113-40362 LIMIT NUT 2
BEARING 2
JUMPER, PCB 3
220-40381 MOTOR, 24VDC, 1/5 HP 1
LIMIT NUT 2
HEX STANDOFF, 6-32 x 1", M/F 4
3 21-40074 XFMR, 120V, 60HV 1
SPROCKET, 41B20, 1/4" KW, (2) 1/4" SS 1
HEX STANDOFF, 6-32 x 1/2", F/F 4
5 23-40050 LIMIT SWITCH 2
KEY, WOODRUFF, 1/4" X 7/8" 1
SCREW, PH PHILLIPS, #6-32 X 1/4" 4
523-40357 SWITCH SPST, TOGGLE 1
Steel shim washer, 1" x 1.5" x 0.010" 1
SCREW, PH PHILLIPS, #6-32 X 3/8" 4
625-40356 CIRCUIT BREAKER, 5 AMP 1
Steel shim washer, 1" x 1.5" x 0.031" 2
729-40089 SONALERT PIEZO ALARM 1
HEX BOLT, 3/8-16 X 1" 4
K74-40065 SERVICE KIT
829-40355 RESISTOR 10 OHM 1
FLANGE NUT, 3/8-16 4
EXTERNAL RESISTOR
9 29-NP712 BATTERY, 12V 7AH 1
E-RING, 1" 1
DESCRIPTION QTY
10 K79-40056 PCB, COMPLETE, FULL SYSTEM 1
EXTERNAL CURRENT RESISTOR
11 K79-40370 PCB, BATTERY CHARGE 1
K74-40084 BRIDGE RECTIFIER ASSEMBLY B
SHRINK WRAP, 1" 2
DESCRIPTION QTY
SCREW, PH PHILLIPS, #2-56 X 1/2" 2
CAPACITOR, RECTIFIER 1
LOCKNUT, #2-56 2
BRIDGE RECTIFIER 1
WIRE, GREEN, 8", STIP X FORK 1
SCREW, PH PHILLIPS, #6-32 X 1" 1
WIRE, YELLOW, 8", STIP X FORK 1
FLANGE NUT, 6-32 1
K75-40346 SERVICE KIT
K75-30349 SERVICE KIT
IDLER SPROCKET
GEAR BOX, W/ SPROCKET
DESCRIPTION QTY
DESCRIPTION QTY
SPROCKET, 41B24, 3/16" KW, (2) 1/4" SS 1
GEAR BOX 1
BEARING, 1/2" ID x 3/4" OD x 1/2" 1
HEX BOLT, 1/4-20 X 3/4" 4
HEX BOLT, 5/8-11 X 2-3/4", GRADE 5 1
LOCKWASHER, 1/4" 4
HEX JAM NUT, 5/8-11 2
KEY, 1/8" X 1-1/8" 1
LOCKWASHER, 5/8 1
SPROCKET, 35B12 X 5/8" BORE 1
K75-40402 SVC. KIT DRIVE SPROCKET H
K74-40386 SVC. KIT, LIMIT SWITCH D
DESCRIPTION QTY
DESCRIPTION QTY
SPROCKET, 41B18, 1/4" KW, (2) 1/4" SS 1
LIMIT SWITCH 2
KEY, WOODRUFF, 1/4" X 7/8" 1
HEX STANDOFF4-40 x 1-1/2 F/F 4
LIMIT SWITCH ACTUATOR PLATE 1
K75-40403 SVC. KIT, REDUCTION SPROCKET J
LOCKNUT, #8-32 2
DESCRIPTION QTY
LOCKWASHER, #4 8
SPROCKET, 35B54, 1" Bore 1
SCREW, PH PHILLIPS, #4-40 X 5/8" 8
KEY, WOODRUFF, 1/4" X 7/8" 1
SCREW, PH PHILLIPS, #8-32 X 1" 2
SPRING, LIMIT PLATE 2
K74-40378 SVC. KIT, OPERATOR COVER K
DESCRIPTION QTY
COVER, SL920 & 930 1
LABEL, LIFTMASTER BUBBLE 1
SCREW, SOCKET, 3/8-16 X 1" 4
WASHER, 5/16, INTERNAL GRIP, PLASTIC 4
INDIVIDAUL PARTS
A
C
E
G
F
12 25-2015 BREAKER 15AMP 1
50-19914 RADIO KIT (OPTIONAL)
DESCRIPTION QTY
412HM RADIO 1
CABLE EXTENSION KIT 1
STICK-ON CABLE FASTENER 2
6-32 x
½PAN HEAD SCREWS 2
6-32 x 1 HEX MALE/FEMALE STANDOFF 2
#6 FLAT WASHER 2
#6 LOCK WASHER 2
#6 NUT
3" STRIP OF FLEX-GROMET
2
1

8
Remove the gate operator from it's
package and make sure that all parts are
included. Refer to General Information and
Parts Identification. If any parts appear to be
missing, contact dealer.
Temporarily plug the operator into
115 Volt outlet or extension cord.
Before beginning installation, test the
gate operator by running the operator back
and fourth 2 or 3 times. If the gate operator
appears to have any shipping damage,
contact a dealer.
The operator may be run back and
fourth by momentarily touching the open input
terminals together. The terminals can be
touched together with a short length of wire,
paper clip or needle nose pliers. With full
systems capability circuit board, the open
input terminals are 5 and 6.
Disconnect Power when finished!
Installation
TEST OPERATOR
1
2

9
Installation continued...
Disconnect Power from the gate
operator!
The tail end of the gate should
extend approximately 24" beyond the edge of
the driveway. If this is not the case, an
extension tail will need to be added to the
gate. This will give room for the gate operator.
Make the extension tail 24" X 24" as shown.
If the gate has not yet been fabricated, add
24" to the length of the gate.
If no concrete surface exists to
attach the gate operator to, make a cement
pad 16" X 24" X 10". The cement pad should
be at least 6" in depth and extend below frost
line. If it is desirable to elevate the gate
operator it may protrude 4" or more above
ground as shown. Place the shortest pad
edge even with the driveway edge. Place the
longer edge of the pad 1" away from the gate.
If the steel mounting stand will be
used, place the shortest edge of the stand 4"
from the driveway edge and place the longest
edge of the stand 4-1/2" away from the gate.
The top of the steel stand may sit on the
ground or the stand may be elevated to keep
the operator above snow, flooding etc. Make
a post hole and cement the stand in place,
making sure the stand is level and square to
the gate.
CEMENT PAD LOCATION
3
4
5
GATE PREPERATION
OPTIONAL MOUNTING STAND

10
Installation Continued...
If the steel mounting stand was used,
simply bolt the gate operator to the stand. If
the operator will be mounted to a concrete
surface or pad, place the shortest edge of the
operator 4" away from the edge of the
driveway. Place the longer edge of the gate
operator 2-1/2" away from the gate.
When the gate operator is correctly
positioned on the concrete surface or pad,
mark the base hole locations onto the
cement with a felt tip marker or equivalent.
Once marked, move the operator to the side
and drill the 4 holes using a 3/8" masonry bit.
Place the operator back into position. Insert
the four sleeve anchors into the holes and
firmly tighten.
Now that the operator is firmly
attached, the chain may now be connected to
the gate and operator. Begin by threading the
chain through the sprockets. The sprockets
come arranged as shown so that the chain
may be threaded under the idler sprockets
and over the drive sprocket. Alternately, the
chain may be threaded over the idler sprock-
ets and under the drive sprocket by moving
the idler sprockets to the alternate positions
above. Note: the cover will need to be modi-
fied for the alternate arrangement.
POSITION GATE OPERATOR
ANCHOR THE OPERATOR
THREADING THE CHAIN
6
7
8

11
Installation Continued...
Attach the gate bracket to the gate
as shown using the round or square u-bolts
for round or square gate frames respectively.
Attach the chain to the gate brackets using
the chain bolt and master link as shown. If
necessary, the chain may be easily short-
ened using a chain breaker. Adjust the height
of the gate brackets until the chain is level
and firmly tighten the u-bolts. For round gate
frames it may be necessary to drive the self
tapping screw through the gate bracket, and
into the gate.
The limit nuts need to be adjusted to
cause the gate to stop in the desired open
and closed positions. These adjustments can
be roughly made before power has been
hooked up by flipping the manual release
switch and pushing the gate manually. Push
the gate to the open position and adjust the
limit nut to press the limit switch in. The limit
nuts can be turned after pressing down on the
guide plate. Push the gate closed and adjust
the other limit nut to press in the other limit
switch. Caution "do not allow the limit nuts to
travel past the switch as this may damage
the switches". When finished, make sure the
guide plate is properly engaged with the
grooves on the limit nuts.
ATTACH CHAIN TO GATE
ADJUST LIMITS
9
10

12
Alternate Installations
The rear mount installation is an
excellent way to conceal the chain or opera-
tor. The operator is placed in the extreme rear
of the gate as shown and the chain never
goes across the driveway. The chain only
goes from the gate operator to a post or wall
beside the driveway. Place shortest edge of
the operator 3" from the rear end of the gate
and place the long edge of the operator 3-1/2"
away from the gate toward the wall.
The chain will form a continuous
loop, going around the drive sprocket on the
operator, and around the idler sprocket on the
post or wall. Only one gate bracket is
required on the rear edge of the gate where
both ends of the chain come together and
attach to the bracket. To prepare the SL920
for a rear mount installation, remove one or
both idler sprockets from the operator.
Neither idler sprocket will be needed on the
gate operator. For the idler sprocket, an
ES130 End Sprocket Assembly with chain
guard may be used. Alternately, an idler
sprocket that was removed from the gate
operator may be used. It is recommended
that a cover be placed over the idler sprocket
in this case for safety.
REAR MOUNT PLACEMENT
CHAIN ARRANGEMENT

13
Electrical
Make sure that power is OFF
before making any electrical connections!
Be sure that all wiring is employed
as required by local codes.
The operator is provided with two
knockout holes on each side. Run 1/2" liquid
tight flexible conduit through one of the four
knockout holes and into the handy box where
the receptacle is located. An elbow fitting is
attached to the handy box and a straight
fitting is supplied for the other end of the
flexible conduit. Run three 12 gauge wires
through the flexible conduit and into the
handy box. There should be a black or other
colored wire for hot, a white wire for neutral,
and a green wire for earth ground.
Connect the three 12 gauge wires to
the 115 Volt receptacle.
Connect the black (hot) wire to the
brass screw.
Connect the white (neutral) wire to
the silver screw.
Connect the green (ground) wire to
the green grounding screw.
When the wires have been connected
to the receptacle, insert the receptacle back
into the handy box. Secure the receptacle to
the handy box with two screws. Apply the
receptacle cover to the receptacle and secure
it with a screw. The power cord may now be
plugged into the receptacle.
To reduce the risk of electric shock,
this equipment has a grounding type plug that
has a third (grounding) pin. This plug will only
fit into a grounding type outlet. Do not change
the plug in any way.
CONDUIT ROUTING
STANDARD 115 VOLT HOOK-UP
3
1
2

14
Electrical Continued...
If the gate operator is already factory
equipped with battery run, only the Right/Left
Side switch and the Mode switch need to be
set. The Right/Left switch simply needs to be
set in the same position as the Right/Left
switch on the main control board. (See page
17 for correctly setting the Right/Left switch
on the control board) The Mode switch can be
set in either the Mode 1 or Mode 2 position.
This choice between Mode 1 or Mode 2
depends on how the installer or end user
would like the gate to behave when power is
lost.
Mode 1: Gate will continue to
operate when power is lost. When battery
power gets low, the gate will open and stay
open until power is restored. (Fail Secure)
Mode 2: Gate will open immediately
when power is lost and remain open until
power is restored. (Fail Safe)
If the gate operator did not come from
the factory equipped with battery run, field
installation of battery run is very simple. The
illustration at left shows additional wiring
required for battery run that is not part of the
standard wiring.
First turn power off to the gate
operator.
Disconnect the brown and red wires
from terminals 13 and 14 and insulate the
ends of the wires.
Secure the charger board to the main
control board by attaching to the 14 screw
terminals on the left side of the control board.
Connect a green wire from terminal 2
to terminal 15 of the control board.
Attach an orange wire from terminal
D of the charger board to terminal 18 of the
main control board.
Finally, attach a red wire from
terminal A to battery positive and a black wire
from terminal B to battery negative.
BATTERY BACK-UP
BATTERY BACK-UP

15
GRY
GRY
1
2
3
4
BLK
RED
SAFETY
N.O.
N.O.
N.O.
N.C.
N.O.
N.O.
OPEN
PULSE OPEN
N.C.STOP
CLOSE
N.O.STOP
412 HM
RADIO RECEIVER
)
)
)
)
)
)
REMOVE JUMPER
IF USING N.C. STOP
PUSH BUTTONS,
KEY SWITCHES, ETC.
24
SWITCH1
RED
LEFT/RIGHT SIDE
OPERATION L R
OFFON
SWITCH2
ORG
COM
GRN
1
2
3
4
SAFETY
OPEN
OPEN
ADJUST
OPEN
ADJUST
TIMER
ADJUST
TIMER
ADJUST
TIMERSWITCH
CLOSE
ADJUST
CLOSE
ADJUST
MOTORPOWER
RELAY
NOTUSED
NOTUSED
RELAYPOWER
RELAYCOIL
RELAYCOIL
START/STOP
RESITOR
START/STOP
RESITOR
ACCESSORYINPUTTERMINALS
ACCESSORYINPUTTERMINALS
LIMITSWITCHES
SWITCH
SENSITIVITY
ADJUSTMENTS
AUTO
CLOSE
TIMER
AUTO
CLOSE
TIMER
PULSE
OPEN
PULSE
OPEN
N.C.
STOP
N.C.
STOP
N.O.
STOP
N.O.
STOP
ACCESSORYPOWER
12V OLTDC/.1AMP
ACCESSORYPOWER
12V OLTDC/.1AMP
CIRCUIT
BOARD
POWER
CIRCUIT
BOARD
POWER
CLOSE
5
6
7
8
9
10
11
12
13
14
15
-
+
+
+
-
-
RESISTOR
RESISTOR
INCREASE
INCREASE
MORETIME
JUMPER18V AC
COM COM COM
EDGE ALARM RADIOCOM
BLU
BLU
VLT
VLT
ORG GRN BLKYLW
YLW
BLU
BLU
16
17
18
19
20
21
22
23
25 26 27
!
104680F
N.C. STOP INPUT: Any device that is used to stop the gate operator while it is running in the open or closed
direction is a stop input device. These stop input devices must provide normally closed contacts. To connect these normally
closed contacts, remove the stop jumper from terminals 8 and 9 and then connect the contacts to these same terminals 8
and 9.
N.O. STOP INPUT: This input functions identical to N.C. Stop with the exception that it requires normally open
contacts. These contacts are connected to terminals 9 and 11.
SAFETY INPUT: Any device that is used to open and/or hold open the gate while the gate is in a non-closed
position is a safety input device. The safety input device must provide normally open contacts. These contacts are connected
to terminals 4 and 6. This function is especially useful when the auto close timer is being used in preventing the gate from
accidentally closing on a vehicle.
PULSE OPEN INPUT: This input functions similarly to the standard open input with the exception that it will not
hold the gate open if the input remains present. This feature will add additional security to the gate operator system in the
event that there is a device that is stuck on. Pulse open is found at terminals 6 and 7.
SAFETY NOTES: Controls must be far enough from the
gate so that the user is prevented from coming in contact with the
gate while operating the controls. Controls intended to be used to
reset an operator after 2 sequential activations of the entrapment
protection device or devices must be located in the line of sight of
the gate. Outdoor or easily accessible controls shall have a
security feature to prevent unauthorized use.
OPEN INPUT: Any device that is used to open
the gate from a closed position is an open input device.
The device used must provide normally open contacts.
These normally open contacts are connected to
terminals 5 and 6. These open input terminals will
cause the gate operator to open and/or close if the
timer switch is in the OFF position. If the timer switch
is in the ON position, these open input terminals will
cause the gate operator to open and will hold the gate
open until the input is released and the auto close time
has elapsed.
CLOSE INPUT: Any device that is used to
close the gate is a close input device. The device used
must provide normally open contacts. These normally
open contacts are connected to terminals 9 and 10.
These close input terminals will cause the gate
operator to close the gate any time the gate is in a
non-closed position and can be used to override the
timer and close the gate prematurely.
Electrical Continued...

16
Wiring Diagrams, Button Controls
zOne button, two button and three button controls may be
connected individually or together as shown below. Most button
controls have a common "buss bar" which connects the common
terminals of all buttons together so that only one common wire
needs to be run back to the gate operator control board. If this is
not the case, the common terminals of each button may be
connected together with wire.
zConnect the common terminal or terminals (COM) of the push
button control to the Common (terminal 6) on the gate operator
control board. Connect the Open button NO terminal of the push
button control to Open (terminal 5) on the gate operator control
board. Connect the Close button NO terminal of the push button control to Close
(terminal 10) on the gate operator control board. If the stop button has normally
closed contacts, connect the Stop button NC terminal to Stop (terminal 9) and
remove the stop jumper that is on terminals 8 & 9. If the stop button has normally
open contacts, connect the Stop button terminal NO to the NO Stop (terminal 11)
on the gate operator control board.
zIf more than one push button control is used on one gate operator, connect
wires from the Open, Close and Common in parallel to the control board. If the
stop button has normally closed, contacts connect the stop buttons in series to
the control board. If the stop buttons have normally open contacts, connect the
stop buttons in parallel to NO Stop (terminal 11) on the control board.

17
Fine Tuning
The gate operator is designed to
work differently while opening then while
closing to optimize safety, so the direction of
the operator will need to be set. Setting the
operator direction is done by flipping the right/
left side switch located at the top of the
circuit board. For a left side installation flip
the switch to the left and for a right side
installation, flip the switch to the right (see
illustration above).
If it is desirable to have the gate
close automatically after the gate has
opened, flip the auto close timer switch to the
ON position. Adjust the amount of time the
gate stays open by turning the timer adjust-
ment pot counter clockwise for less time or
clockwise for more time. The range is roughly
0~45 seconds.
For protection of the over all system
there are two "sensitivity" adjustments on the
circuit board for the open and close direc-
tions. Turning the pots clockwise "increase"
will cause the gate to stop or reverse more
easily if there is an obstruction preventing the
gate from moving. Turning the pots counter-
clockwise "decrease" will cause the gate to
push harder before it stops or reverses. If
adjusted properly, the sensitivity will cause
the gate to reverse if the gate meets an
obstruction. Additionally, if the gate again
meets an obstruction before reaching a limit,
the gate will stop, remain stopped, and will
sound an alarm until reset with an open input
at terminal 5. If no reset is given, the alarm
will sound for approximately 5 minutes. If
adjusted too sensitive the gate may stop or
reverse under it's own weight, without being
obstructed and the sensitivity will need to be
slightly decreased. Temperature, wind, and
other environmental factors may also effect
the sensitivity, so the setting should be made
with these factors in mind. Before finalizing
an installation always test the sensitivity by
applying pressure against the gate while it is
moving to make sure it will stop or reverse.
ADJUST TIMER
ADJUST SENSITIVITY
NOTE:
Counter-Clockwise makes gate push harder.
Clockwise makes gate easier to stop.

18
zConnect 115 Volts AC to each SL920 gate operator. Connect the four Master/Second wires from the master circuit board
to the Second circuit board as shown below. Any operator can be used as either a master or a Second. Accessories can be
connected to the master or second operator.
zSwitch the Auto Close Timer switch to the OFF position on the Second circuit board. The Auto Close Timer switch on the
master circuit board may be switched either ON if the timer function will be used or OFF if the timer function will not be used
but the Second timer must always be switched OFF.
zIf the chain is wrapped around the sprockets in the same manner on each operator (both chains under or both chains over
the drive sprocket) set the Right/Left Side Operation switch on the master circuit board to be the opposite of the way it is set
on the Second circuit board. If the chain wrapped around the drive sprocket on the master operator is the opposite of the way
it is wrapped around on the Second operator then set the Right/Left Side Operation switches the same on both operators.
The Right/Left Side operation switch is located on the circuit board. If the operators are working backwards, the Right/Left
Side Operation switches on both operators must be switched. The simplest way to know if the operators are working back-
wards is to turn the Auto Close Timer switch on the master circuit board to ON and see whether the timer works when the
gate is open or closed. The timer should work only when the gate is open. Another way to know if the operators are working
backwards is to try the gate sensitivity by applying pressure against the gate while the gate is opening or closing. If pressure
is applied while the gate is opening it should stop. If pressure is applied while the gate is closing it should reverse and go
open. If the gate responds to pressure in a way that is opposite of this then switch the Right/Left Side Operation switch on
both operators.
SL920 MASTER/SECOND
Master/Second Wiring
MASTER SECOND

19
Wiring Diagram SL920 WITH FULL SYSTEMS CAPABILITY

20
Wiring Diagrams SL920 WITH BATTERY BACK-UP
BREAKER
15 AMP