RITE-HITE APB-1000 User manual

APB-1000
Hydraulic Dock Leveler
Owner’s Manual
Printed in U.S.A. Publication No. 1120-R5
Copyright 1997, 2000 June 2000
DANGER
APB-1000/Rev5 6/1/00 7:48 AM Page a

SAFETY WARNINGS
LOCKOUT/TAGOUT PROCEDURES
The Occupational Safety and Health Administration requires that, in addition to posting safety warnings and barri-
cading the work area, including but not limited to trucking office and loading docks, that the power supply has been
locked in the OFF position or disconnected. It is mandatory that an approved lockout device is utilized. An example of
a lockout device is illustrated. The proper lockout procedure requires that the person responsible for the repairs is the
only person who has the ability to remove the lockout device.
In addition to the lockout device, it is also a requirement to tag the power control in a manner that will clearly note that
repairs are under way and state who is responsible for the lockout condition. Tagout devices have to be constructed
and printed so that exposure to weather conditions or wet and damp locations will not cause the tag to deteriorate or
become unreadable.
RITE-HITE®does not recommend any particular lockout device, but recommends the utilization of an OSHA approved
device (refer to OSHA regulation 1910.147). RITE-HITE®also recommends the review and implementation of an entire
safety program for the Control of Hazardous Energy (Lockout/Tagout). These regulations are available through OSHA
publication 3120.
When working with electrical or electronic con-
trols, make sure that the power source has been
locked out and tagged according to OSHA regu-
lations and approved local electrical codes.
The statements used with this level of warning
deal with a safe operating procedure. If the pro-
cedure is ignored the possibility of personal
injury may exist.
This is the highest level statement. Failure to
follow the listed instructions will most likely
result in severe injury or death.
This is a statement of serious hazard. Failure to
follow the listed instructions could place the
individual at risk of serious injury or death.
IMPORTANT is used to draw attention to a pro-
cedure that needs to be followed to prevent
machine damage.
APB-1000/Rev5 6/1/00 7:48 AM Page b

SAFE-T-STRUTTM
Post warnings and barricades at dock level
and at drive level that work is being done around
and under the leveler platform. Lockout and
tagout power to the APB-1000 dock leveler and
post warnings when work is being performed on
the unit.
ENGAGING SAFETY STRUT
Never be under the APB-1000 platform or lip
without:
•Engaging the SAFE-T-STRUTTM. See below
right. This can be done with the assistance of
another person by:
Press PLATFORM RAISE until platform
reaches its highest position. While holding
PLATFORM RAISE, press LIP EXTEND until lip
fully extends. Release PLATFORM RAISE and
continue to hold LIP EXTEND/MOMENTARY
PAUSE.
Then insert the smaller end of the
SAFE-T-STRUTTM through the hole in the
middle of the leveler lip and place the strut’s
broader open end over the pin located on the
leveler’s front frame. Align the holes on the pin
and the SAFE-T-STRUTTM so that the leveler
may be locked and tagged out with the
retaining pin and chain.
Release the pushbuttons, allowing the leveler
platform to rest on the strut.
•The power may now be locked and tagged out.
–Turn off the power to the control box.
–Lock and tag out the main power sources, as
shown under Safety Warnings.
–Always barricade the APB-1000 from any
form of traffic.
•For strut removal, raise leveler to highest posi-
tion with lip fully extended, lift strut off base,
and remove strut from lip.
•If you are unable to install the
SAFE-T-STRUT™contact RITE-HITE®at
1-800-456-0600.
SAFETY DEVICES
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APB-1000/Rev5 6/1/00 7:48 AM Page d

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i
DEFINITION OF FEATURES ON THE APB-1000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
OPERATING INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
OPTIONAL EQUIPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
REPLACEMENT PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Pub. No. 1120-R5 — June 2000 i
TABLE OF CONTENTS
INTRODUCTION
RITE-HITE®’s model APB-1000 hydraulic dock leveler provides a practical alternative to applications where “basic
automatic operating characteristics” are desired. The unit is operated by a single, remote pushbutton control box.
Lip extension is achieved through positive mechanical linkage, meaning that as the ramp raises hydraulically to full
up the lip extends mechanically. An electro-hydraulic power unit delivers hydraulic oil to a heavy duty cylinder which
includes an emergency safety system which restricts uncontrolled platform drop.
The RITE-HITE®products in this manual are covered by one or more of the following U.S. patents: 4,373,847; 4,379,354;
4,443,150; 4,472,099; 4,560,315 (RE: 32,968); 4,605,353 (RE: 33,154); 4,634,334; 4,692,755; 4,843,373; 5,212,846;
5,297,921; 5,375,965; 5,453,735; 5,531,557; 5,553,987; 5,582,498; 5,664,930; 5,702,223; 5,762,459; and pending
U.S. and foreign patent applications. RITE-HITE®, GUARDRITE®, SAFE-T-LIP®, HYDRACHEK®, WHEEL-LOK™,
DOK-LOK®, DUAL-DOK®, and SAFE-T-GATE™ are trademarks of RITE-HITE®.
APB-1000/Rev5 6/1/00 7:48 AM Page i

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Pub. No. 1120-R5 — June 2000 1
DEFINITION OF FEATURES
ON THE APB-1000
Lip Lip Hinge
Pin
Lip Connecting
Link
Lip Crank
Weldment Hydrachek Platform
Rear Ramp
Hinge Pins
Front Return Spring Rear
Subframe
Rear NutSnubbing Cable
Lip Stop
Bolt
Front Rear
Ramp Lifting
Cylinder
Power Unit Main Cylinder Hose Velocity Fuse
(LS1)
Restrictor
Limit Switch
(Optional)
(LS2)
Automatic
Return To Dock
Limit Switch
(Optional)
Front Rear
Power CordPower Unit
HYDRAULIC COMPONENTS
MECHANICAL COMPONENTS
ELECTRICAL COMPONENTS
Lip Keepers
Front
Nut
Lip Assist
Spring
FIGURE 1 —LEVELER FEATURES
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2Pub. No. 1120-R5 — June 2000
See Figure 1 for locations of these features.
LIP
The extendible portion of the dock leveler which pro-
vides a bridge from the platform to the bed of the trailer.
The leveler lip features seamless steel tube lip hinges. A
hole is drilled in the lip to allow the insertion of the
RITE-HITE®SAFE-T-STRUT™. Additional details on the
SAFE-T-STRUT™ are given later in this section.
LIP KEEPERS
The lip keepers provide a structural support when the lip
is not on the bed of a trailer. They provide support for at
dock end loads, cross traffic and maintain security for
the dock position when not in use.
LIP STOP BOLT
The lip stop bolt controls the position of the lip when it is
pendant. The bolt is properly adjusted at the factory. For
levelers with a 16" lip, field adjustment is seldom required.
Levelers with 18" or 20" lips may require field adjustment
as the two lip keepers must be field welded to the front pit
curb angle; the lip keepers for 18" and 20" lips are tack
welded to the leveler subframe for shipment.
SUBFRAME
The subframe of the APB-1000 supports the platform
and protects the motor and the hydraulic fluid reservoir.
PLATFORM
The platform, along with the lip, provides the main
bridge between the dock and the trailer bed. It is hinged
at the rear of the subframe, and automatically adjusts
with the position of the trailer bed. The platform is con-
structed in a four-sided box structure with a bridge bar
at the header cutout. Sturdy 12 gage structural steel
toeguards prevent possible injury at the sides of the
leveler.
RAMP LIFTING CYLINDER
The ramp lifting cylinder is a single acting hydraulic
piston of heavy duty construction grade, non-adjustable,
with a 3-1/2" diameter piston and a 1-1/2" diameter rod.
When the power unit is energized, the cylinder extends,
lifting the platform. When power is removed, the plat-
form’s weight compresses the cylinder, allowing the
entire unit to float onto the bed of a trailer. The inverted
cylinder maximizes leveler strength in the event of
“Emergency Drop.”
POWER UNIT
This is the electric-hydraulic motor which pumps
hydraulic fluid to the ramp lifting cylinder. The power
unit package consists of a 3/4 hp 120V or 240V single
phase electric motor, a 1.4 GPM gear pump, a 1.0
gallon capacity hydraulic fluid reservoir, and all valving.
The hydraulic oil reservoir contains a top mounted com-
bination breather filler cap. Hydraulic oil can be added to
the system by removing the cap and pouring oil into the
reservoir.
NOTE
When adding oil, use only MIL-H-5606 or equal.
BELOW DOCK CONTROL CHAIN
Pulling on the below dock control chain as the leveler
platform is descending permits the leveler to fall to a
below dock level position. This is useful when servicing
trailers that are not the same height as standard trailers.
The below dock control chain is reset whenever the
leveler is returned to dock height.
SAFETY STOP SYSTEM
The hydraulic system has an emergency flow control
stopping valve (velocity fuse) that prevents the leveler
from “free-falling” in emergency conditions. The valve is
in line with the hydraulic oil hose at the ramp lifting
cylinder.
See Figure 11, page 13 for location of
SAFE-T-STRUT™and Base.
SAFE-T-STRUT™AND BASE
The APB-1000 leveler is shipped with the RITE-HITE®
SAFE-T-STRUT™. This SAFE-T-STRUT™ is inserted
through a pre-drilled hole in the lip and then secured by
placing the end of the strut on the SAFE-T-STRUT™
base. The SAFE-T-STRUT™ increases the level of
safety for workers when installing equipment or per-
forming routine maintenance, and must be used every
time service is being performed on the unit.
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Pub. No. 1120-R5 — June 2000 3
PRIOR TO INSTALLATION
1. Verify pit dimensions to certified pit drawings. Read
and study the Pit Details on page 4.
2. Leave shipping bands in place on the APB-1000
until you are instructed to remove them.
3. Clean pit of all debris.
NOTE
The control box is shipped strapped to the underside of
the leveler.
An operational sign is attached to the dock leveler frame
and should be removed prior to placing the unit in the
pit.
Levelers with 18" or 20" long lips require field installation
of lip keepers. The keepers are tack welded to the inside
frame for shipment. To install, level the subframe of the
leveler first (refer to page 6, Installation Details). With
the lip in the pendant position, locate and weld lip
keepers so that the platform is flush with the dock floor
and the lip is tightly set inside the keeper pockets.
INSTALLATION PROCEDURES
1. Hoist leveler into pit with the chain and handling
plate assembly attached in forward handling holes.
See Installation Details on page 6.
2. Carefully remove shipping bands from the lip.
NOTE
Unit may be mechanically raised. If leveler is mechani-
cally raised, it will require at least 10 full cycles of the
unit after installation to purge air from the hydraulic
system.
3. Align rear of leveler flush with the dock floor. Tack
weld the rear edge of the leveler frame to the
embedded pit angle. Add shims under each rear
post for complete support between the leveler
frame and pit floor. See the Installation Details on
page 6.
(continued on page 8)
INSTALLATION INSTRUCTIONS
Be sure to follow these Caution notes when
installing your APB-1000 hydraulic leveler.
1. Disconnect electrical power according to
OSHA Lockout/Tagout standards.
2. DO NOT ground welding equipment to
hydraulic cylinder or electrical components.
Only ground to sub-frame of leveler for
welding shims prior to installation. DO NOT
ground to platform as damage to equipment
may result.
3. Tack a small piece of steel to pit steel for
grounding welding equipment while welding
unit into pit.
4. DO NOT connect green ground lead of
leveler wiring until all welding is complete.
Make sure that the lifting unit, or picker crane, is
capable of lifting 3,000 lbs.
1. DO NOT cut shipping bands until the leveler
is placed in the pit.
2. Shipping bands are under tension. Stand to
the side when cutting.
Cover cylinder with flame retardant covering
before welding cylinder shims.
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4Pub. No. 1120-R5 — June 2000
PIT DETAILS
CONSTRUCTION NOTES
1. Concrete behind pit steel must be well vibrated.
2. Rear pit wall must be square with dock floor.
3. All curb angle joints to be welded securely.
4. Junction box 4" x 4" x 2" NEMA 4 (by others),
minimum 3/4" diameter conduit required.
5. 1/2" pitch toward front of pit for drainage.
6. Both bumper mountings must be the same design.
7. For plug in optional hookup, junction box must be
per R-H drawing AI-1835.
CAPACITIES B+, D, F
Nominal Pit Sizes 6' x 6' 6'6" x 6' 7' x 6' 6' x 8' 6'6" x 8' 7' x 8'
Pit Length Dim. A 63 63 63 87 87 87
Pit Width Dim. B 74 80 85 74 80 85
Pit Depth Dim. C 19-1/2 19-1/2 19-1/2 19-1/2 19-1/2 19-1/2
Dim. A
Tolerance
+ 1/4-0
Dock Floor
Control Box
Dock
Face
1/2" Pitch
Driveway Approach
Item 1
Front Curb Angle
Item 4
Alternate Bumper
Mounting Angle
Item 4
Horizontal Bumper
Mounting Angle
Dim. B
Tolerance
±1/8
Dim. C
Tolerance
±1/8
Item 6
Alternate
Junction Box
And Conduit
Location
Item 6
Preferred
Junction Box
And Conduit
Location
14"
Item 3
Side Curb Angle
(2) Required
Item 2
Rear
Curb Angle
Item 5 (Optional)
DOK-LOK®Mounting Plate
14"
27-1/2"
10"
90°
C
L
Dim. B
Tolerance
±1/8
Due to the vast number of variations in pit design, using these RITE-HITE®approved pit details may not be
possible. If you require an alternate pit design, it will be the responsibility of your contractor to design a
pit in accordance with federal, state, and local codes. For more information, contact your local RITE-HITE®
representative.
FIGURE 2 —PIT DETAILS
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Pub. No. 1120-R5 — June 2000 5
Junction Box 4" x 4" x 2"
NEMA 4 (By Others), Minimum
3/4" Diameter Conduit Required.
Fused Disconnect Equipped With Lock-out
Tag-out Hasp Device. Supplied And Installed
By Others.
To Customer’s Power Supply 120V 1 PH 60 Hz
*NOTE: 15 AMP Circuit Breaker For 240V 1PH 60 Hz (3/4 HP)
20 AMP Circuit Breaker For 120V 1PH 60 Hz (3/4 HP).
One Leveler Per Overload Protection Device.
Typical Electrical Installation
Pushbutton Control Box NEMA 12
(Supplied By RITE-HITE®)
Conduit By Others.
Side
Pit Wall
Alternate
Location
10"
Ref.
14"
27-1/2" Ref.
14"
Of Pit
Pit Floor
C
L
48"
3/4"Diameter
Minimum Conduit
Unless Otherwise
Specified
Preferred
Location
ELECTRICAL INSTALLATION DETAILS
FIGURE 3 —ELECTRICAL INSTALLATION
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6Pub. No. 1120-R5 — June 2000
1"
Clearance
Bumper
Steel Bumper
Mounting
Right Hand
Side Curb Angle
NOTE: Only B+
6' and 6.5'
Wide Levelers
Have 3 Posts.
All Others
Capacities Have
5 Posts.
Weld Three Or Five Shims Under Support Posts,
Depending On Width And Capacity, Prior To Installation.
Shim Size 3" Wide x 4" Long x Height*.
(2 Shim Packs)
4" x 6" x Height*
Mount Directly
Beneath The Cylinder
Clevis And Weld
To Frame.
8"
4"
6"
1-3/4"
Full Weld Both Sides
(4 Shim Packs)
TOP VIEW
Pit Without Leveler
Top Rear Pit Angle
NOTE: If No Shimming Is Required At Front Frame Angle,
A Minimum 3/8" x 6" Long Fillet Weld Is Required At The
Four Locations Shown.
All Welds Are 3/8" Minimum, Unless Otherwise Indicated.
Refer To AI-1827 Page 2 For Installation Of Deep Pit Conversion.
Reference AI-1837 For Deep Pit Frame Conversion.
*Height Of Shim Pack Will Vary Depending On Pit Depth.
Dock Floor Top Of Leveler
Level
Rear Front
Shipping
Bands
Lip
Keepers
Shims
Pit Floor Front Curb Angle
Rear
Support
Post
NOTE: Install
Bumpers With
Laminations
Vertical.
1"
TOP VIEW
With Leveler In Pit
6" Long Behind Hinges
(3 Or 5 Places,
Depending On Width)
NOTE: Installation May Be Done
From Dock Floor Or Driveway.
Dock Floor
Top Rear Curb Angle
Side Curb Angle
Pit Floor
Dock Face
Front Curb Angle
Lip Keepers For Levelers With
18" Or 20" Long Lips Are “Tack
Welded”To Inside Of Frame For
Shipping. These Must Be Field
Installed. See AI-1837.
Power
Cord
Pit
Leveler
Lip
Shipping
Bands
Top Of
Leveler
Top Of
Leveler
Handling
Plate
SIDE VIEW
Front Rear
Motor
Frame
Suggested Handling Plate
(Supplied By Others)
Mat’l.: 3/8" x 3" x 8" Long H.R.S.
1-1/2"
2-1/2"
1-3/4"
3"
15°
1"
1" Dia. Pin 2" Lg.
8" Flat
2"
Dia.
3/8"
C
L
Directly Beneath Front Frame Angle In Line With
Header Stops, Snubbing Cable And SAFE-T-STRUT™.
Shim Size 3" Wide x 4" Long x Height*.
FIGURE 4 —INSTALLATION DETAILS
INSTALLATION DETAILS
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Pub. No. 1120-R5 — June 2000 7
Motors
Incoming Line
Voltage
(from electrical
sources)
120 Volt –
1 Phase 10 30
240 Volt –
1 Phase 5 15
Distance in Feet Between Leveler’s Control
Phase/Voltage Box and Power Source (Circuit Breaker)
For 3/4 HP Units 0 – 100 100 – 200 200+
Single Phase 120 Volts 12 Ga. Wire 10 Ga. Wire 10 Ga. Wire
Single Phase 240 Volts 14 Ga. Wire 12 Ga. Wire 12 Ga. Wire
WIRE SIZES/GAGE CHART
Normal Voltage & Amperage
NOTE: Variations of line voltage will offset motor performance.
Running Amps
Starting Amps
ELECTRICAL INSTALLATION DETAILS

60 Hz
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8Pub. No. 1120-R5 — June 2000
4. Weld front shims, full, to front frame angle and
curb steel. Weld shims under cylinder mount.
Place (5) 3/8" x 6" long welds at rear curb steel
to join the leveler rear frame angle and curb angle.
See the Installation Details on page 6.
5. Complete electrical hookup. See the Electrical
Installation Details on page 7. Connect electrical
power.
6. Remove the SAFE-T-STRUT™, store in the proper
location on the framework, and return the leveler to
the stored position. Add additional shims where
necessary to raise the leveler flush with dock level.
7. Press the RAISE button until the lip is fully
extended. Secure the leveler by inserting the top of
the SAFE-T-STRUT™ through the pre-drilled hole
in the lip, then securely fit the bottom of the
SAFE-T-STRUT™ into the SAFE-T-STRUT™ base.
Lockout and tagout electrical power according to
OSHA regulations and disconnect leveler power.
8. Remove weatherseal from subframe if supplied.
NOTE
Side weather seal is secured inside the frame for
shipping.
9. Remove shipping bolts from the full-range toe-
guards. Remove shipping hooks from the front of
the frame angle (only used with 18" and 20" lips
when lip keepers are shipped loose).
10. Install bumpers as shown in the Installation
Details; weld or bolt in position.
11. Clean and paint all welds.
12. Restore electrical power. Test operate the leveler to
make sure that the unit functions properly.
NOTE
If the leveler has a jerky action when the ramp comes
up, operate the unit about 10 full cycles to remove air
from the hydraulic system. Also check the oil level. See
the Maintenance Section for more information on
checking the oil level.
Full-range toeguards will drop into position. DO
NOT stand underneath.
APB-1000/Rev5 6/1/00 7:48 AM Page 8

NORMAL OPERATION
1. Press and hold the RAISE button on the control
box. Press button until the leveler is fully raised
and the lip is fully extended. See Figure 5.
2. At fully raised position, release the RAISE button.
The leveler will descend by gravity onto the trailer
bed. See Figure 6.
Pub. No. 1120-R5 — June 2000 9
OPERATING INSTRUCTIONS
1. DO NOT hold lip out by hand or serious
injury will occur.
2. DO NOT stand on the leveler while it is in
motion.
1. DO NOT operate until a truck is parked in
place against the dock bumpers or damage
to the unit may occur.
2. DO NOT operate dock leveler with anyone
standing in front of the dock leveler.
3. The wheels of the truck/trailer must be
chocked and/or the truck/trailer locked to
the dock with a vehicle restraint to prevent
the possibility of the truck/trailer rolling
away from the dock.
4. Always return the leveler to the stored posi-
tion when it is not being used for loading or
unloading.
5. Remove wheel chocks and/or release the
vehicle restraint only when loading or un-
loading is finished.
6. At every 30 day maintenance period, inspect
your dock leveler to ensure that there are no
broken or worn parts which could cause
injury to personnel or damage to equipment.
7. If a malfunction does occur, always call
your authorized RITE-HITE®service repre-
sentative.
FIGURE 5 —RAISE LEVELER
FIGURE 6 —LOWER LEVELER
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10 Pub. No. 1120-R5 — June 2000
3. To retract and store the lip while the truck remains
in position, jog (push and release) the RAISE
button just long enough for the lip to fold clear of
the truck. See Figure 7.
4. When the truck departs after all loading or
unloading is finished, the leveler descends to its
lowest position. To reset the leveler, push and hold
the RAISE button on the control box until the
leveler is 10" to 12" above dock level. Release the
RAISE button. The leveler returns to its normal,
stored position with the lip resting securely in the
lip keepers.
BELOW DOCK LOADING
AND END LOADING
NOTE
End loads at dock level and above can be handled with
the leveler in its stored position.
1. Push and hold the RAISE button on the control
box until the leveler is about 10" to 12" above dock
level. See Figure 8.
2. Release the pushbutton and immediately pull and
hold the below dock control chain as the leveler
descends to full below dock. The lip will clear the
keepers as the leveler comes to a rest at its lowest
position. Release the below dock control chain.
See Figure 9.
NOTE
After below dock end loading is complete, the
leveler can be operated using Normal Operation.
Always restore the leveler to dock level when
loading/unloading is finished.
3. Once below dock loading or end loading is com-
plete, push and hold the RAISE button on the
control box until the leveler is 10" to 12" above
dock level. This resets the below dock controls.
Release the RAISE button. The leveler returns to
its normal, stored position with the lip resting
securely in the lip keepers.
FIGURE 7 —STORE LEVELER
1. DO NOT walk on the lip.
2. DO NOT use a fork lift truck to lower the
leveler.
3. DO NOT stand on the leveler while it is in
motion.
FIGURE 8 —BELOW DOCK END LOAD
Below Dock
Control Chain
FIGURE 9 —BELOW DOCK POSITION
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Pub. No. 1120-R5 — June 2000 11
AUTOMATIC RETURN TO DOCK
The limit switch assembly turns the hydraulic pump/motor
assembly on and off to recycle the leveler from below
dock level safely back to dock level with the lip stored in
the lip keepers.
In the APB-1000, two limit switches and a recycle flag
make up the automatic return to dock assembly. LS1 is
the restrictor limit switch and LS2 is the automatic return
to dock limit switch. Both switches are wired normally
open and are rated for 1 HP.
When the platform is falling from a fully raised position,
LS1 will be held closed from approximately six inches
above dock height and lower. Once the leveler reaches its
lowest point, the lip begins to fall. As the lip falls, the actu-
ator paddle moves toward LS2 and holds LS2 closed.
Once both limit switches are held closed, this completes
an electrical circuit; the pump is energized and the plat-
form rises. As soon as the platform rises enough that the
actuator paddle moves back over LS2, signaling that the
lip is pendant, the limit switch arm springs back to the
open position and the hydraulic pump/motor stops. The
platform falls, allowing the lip to land in the lip keepers.
AUTOMATIC RETURN TO DOCK
OPERATION (Optional)
1. Press and hold the RAISE button on the control
box. Press button until the leveler is fully raised
and the lip is fully extended. See Figure 5.
2. Release the RAISE button. The leveler will
descend onto the trailer bed. See Figure 6.
3. When the truck departs after all loading or
unloading is finished, the leveler descends to its
lowest position. The lip will fall to a near pendant
position, activating the automatic return to dock
limit switch. The leveler automatically returns to the
stored position without any need for an operator.
OPTIONAL EQUIPMENT
1. DO NOT walk on the lip.
2. DO NOT use a forklift truck to lower the
leveler.
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12 Pub. No. 1120-R5 — June 2000
OVERHEAD DOOR INTERLOCK
AND SAFETY SWITCH (Optional)
The function of the overhead door interlock is to provide
protection for overhead doors working in conjunction
with hydraulic levelers. The door must be open before
the leveler can be operated, preventing overhead door
damage.
The design uses a limit switch mounted on the door
track. The switch is closed only when the door has been
opened, enabling the leveler RAISE button. If the switch
is open, no power will be available to the dock leveler
control box.
The interlock switch can be installed and wired to almost
any overhead door and hydraulic leveler, regardless of
manufacturer. See Figure 10 for details.
L1 L2 G
LS1
Pushbutton
Box
T1 (Black)
1L1 (Black)
T1 (Black) 1L2 (White) G (Ground)
PB1
“Raise”
Optional
O.H.D. ITL
Limit Switch
For Customer Main Power &
Safety Protection Device
120V 1 PH 60 Hz, 20 Amp Rated Circuit.
(Fused Disconnect Supplied By Others)
(20 Amp Dual Element Fuse)
Source
Use Minimum #12 Gage, 60°/75°Copper
Wire/100 Ft. Of Run –20 Amp Circuit 120V
1/2
1
1-5/8
2
2
9
(2) 1/4
Dia.
#8244 OHD Kit
#55755 Limit Switch
SPST Limit Switch
W Omnidirectional Wire Wand
Wired Normally Open
(1HP Rated, 20 Amp)
A
A
Top Of Door
(See Detail B-B)
Mounting Bracket DetailSection A - A
Adjust Limit Switch
And Mtg. Bracket
As Required To
Activate Switch With
Dimensions Shown.
(Note: Other Angle Or Plate
Actuators May Be Attached
To Door To Activate Switch
As Required).
FIGURE 10 —INTERLOCK SWITCH INSTALLATION AI-1843
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Pub. No. 1120-R5 — June 2000 13
Routine maintenance is required to keep your leveler
functioning properly. Be sure to check the hydraulic fluid
level when servicing your APB-1000 leveler. When
adding fluid to the hydraulic system, only use MIL-H-5606
hydraulic fluid or equal.
LUBRICATION
1. Barricade the leveler off to all forms of traffic.
2. Raise the leveler to the fully raised position.
Secure the leveler by inserting the top of the
SAFE-T-STRUT™ through the pre-drilled hole in
the lip, then securely fitting the bottom of the
SAFE-T-STRUT™ onto the SAFE-T-STRUT™
base.
3. Shut off power at the disconnect switch and
lockout/tagout according to OSHA regulations.
4. Remove all debris from the leveler and pit. Be sure
the hinge section of the lip and platform is clean.
NOTE
Lubrication to be performed every 30 days.
5. Use SAE 30 wt. oil on rear hinge pins, clevis pins,
and all moving parts, as well as each lip, lip push-
rod assembly, and ramp spool (hinge tube). Do not
lubricate cylinder pins with oil. See Figure 11.
6. Grease each lip/ramp spool if equipped with
optional automotive type grease fittings and main
cylinder top pin.
7. Apply factory supplied anti-seize lubricant on lower
cylinder clevis pin and on the lip extension
mechanism.
SAE 30 Oil –On Rear Hinge
Pins, Clevis Pins And All
Moving Parts And Each Lip
And Ramp Spool (Hinge Tube)
Except Cylinder Pins And
Lip Pushrod.
Grease Each Lip/Ramp Spool
And Top Cylinder Clevis Pin
With A Moly Base Grease.
Factory Applied Anti-Seize
Lubricant On Lower Cylinder
Clevis Pin, And Lip Extension
Mechanism.
Lubrication To Be
Performed Every 30 Days.
SAFE-T-STRUT™
B+ Shown With Dashed Posts
2
2 2 2 2 222
222222
3
1
1
DANGER
1
23
Lubricate
All Hinges
SAFE-T-STRUT™Base
FIGURE 11 —LUBRICATION
MAINTENANCE
1. DO NOT work under any leveler without bar-
ricading the leveler and the work area.
2. DO NOT work under any leveler without
firmly supporting the platform and lip with
the SAFE-T-STRUT™.
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14 Pub. No. 1120-R5 — June 2000
ADJUSTMENTS
LIP ASSIST ADJUSTMENT PROCEDURE
Toggle Linkage Adjustment
1. Fully raise the leveler and insert the
SAFE-T-STRUT™.
2. Align a straight edge along the bottom of the Lip
Pin and Lip Crank Pivot Pin. See Figure 12.
3. Measure the perpendicular distance between the
top of the straight edge and the bottom of the Link
Pin with a ruler or tape measure. See Figure 12.
This measurement is the Pin Center Distance.
4. The Pin Center Distance should be within the
range specified in Table 1 for the correct Lip
Length and Capacity of the Leveler being adjusted.
If the Pin Center Adjustment is within the specified
range, move to Lip Assist Spring/Lip Fall Adjust-
ment. If not, continue on to step 5.
5. Loosen the rear Jam Nut. See Figure 13.
If the Pin Center Distance is higher than the range
specified in Table 1, then turn the Rear Adjustment
Nut Clockwise to rotate the Boomerang. This will
decrease the Pin Center Distance. (See Figure 13
for correct direction to move nut.)
If the Pin Center Distance is lower than the range
specified in Table 1, then turn the Rear Adjustment
Nut Counterclockwise to rotate the boomerang.
This will increase the Pin Center Distance. (See
Figure 13 for correct direction to move nut.)
6. Tighten the Rear Jam Nut to the Rear Adjustment
Nut, being careful not to move the Rear Adjust-
ment Nut.
Lip Assist Spring/Lip Fall Adjustment
Proper adjustment of the Lip Assist Spring allows
jogging (push and release) of the RAISE button to
initiate lip break while the platform is floating toward the
below dock stops.
Units manufactured prior to July 1, 1999 (1/2"
HYDRACHEK®mounting pins) — Lip break will initiate
within 2 to 6 seconds after the platform hits the below
dock stops after completely lowering from the full open
position.
Units manufactured after July 1, 1999 (3/8"
HYDRACHEK®mounting pins) — Lip break will initiate
immediately after the platform hits the below dock stops
after completely lowering from the full open position.
1. Remove the SAFE-T-STRUT™ and allow the plat-
form to lower fully onto the below dock stops.
Observe the lip action.
2. If the lip breaks (starts to lower) prior to the plat-
form reaching the below dock stops, more Lip
Assist Spring pressure is needed. Fully raise the
leveler and install the SAFE-T-STRUT™. Increase
the pressure by tightening the Front Lip Assist
Adjustment Nut. (See Figure 13 for correct direc-
tion to move nut.) One quarter to half a turn clock-
wise at a time.
If the lip does not break at all, less Lip Assist Spring
pressure is needed. Fully raise the leveler and install
SAFE-T-STRUT™. Decrease the pressure by loos-
ening the Front Lip Assist Adjustment Nut. (See
Figure 13 for correct direction to move nut.) One
quarter to half a turn counterclockwise at a time.
3. Tighten the Front Lip Assist Jam Nut to the Front
Lip Assist Adjustment Nut, being careful not to
move the Front Lip Assist Adjustment Nut.
4. Confirm that unit is operating properly.
a) Lip remains fully extended until platform
reaches the below dock stops.
b) Lip break will initiate by jogging (push and
release) the RAISE button while the platform
is floating downward.
1. Always clean and lubricate leveler and lip
hinge prior to attempting any adjustments.
2. Always barricade your dock leveler off to any
form of traffic when maintenance is required.
3. Always brace the leveler securely and safely
with the SAFE-T-STRUT™when maintenance
is required.
Table 1 —Pin Center Dimensions
Capacity
Lip Length B+ D F
16" 7/8" – 1" 7/8" – 1" 5/8" – 3/4"
18" 7/8" – 1" 5/8" – 3/4" 3/8" – 1/2"
20" 5/8" – 3/4" 3/8" – 1/2" 3/8" – 1/2"
APB-1000/Rev5 6/1/00 7:48 AM Page 14