RITE-HITE Dok-Lok STR-4000 User manual

This Manual Covers Serial No. 05GD150001W And Up
PRINTED IN U.S.A. RITE-HITE PRINT SHOP PUBLICATION NO. 1191
Copyright 2004, 2005 AUGUST 2005
STR-4000 Dok-Lok®
Vehicle Restraint
Owner’s Manual
MADE IN U.S.A.

RITE-HITE STR-4000 DOK-LOK Owner’s Manual
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SAFETY WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
OWNERS RESPONSIBILITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
DEFINITION AND FUNCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
OPERATING PROCEDURE . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
HORN OVERRIDE CODE AND DIAGNOSTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
COMPONENT TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
ELECTRICAL SCHEMATIC - STAND ALONE POWER UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
ELECTRICAL SCHEMATIC - COMBINATION POWER UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
HYDRAULIC SCHEMATIC - STAND ALONE POWER UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
HYDRAULIC SCHEMATIC - COMBINATION POWER UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BACK COVER
INTRODUCTION
Read and understand this manual before attempting to install or operate any DOK-LOK vehicle restraint. For best
results, have this product serviced by your authorized RITE-HITE representative. The STR-4000 DOK-LOK vehicle
restraint by RITE-HITE is intended to provide a safer workplace for workers in shipping and receiving dock areas. The
STR-4000 DOK-LOK vehicle restraint is an hydraulic restraint device that, when properly installed and operated,
retains a secure connection between the truck and dock. Signal lights and signs provide instructions to the truck driver
and DOK-LOK vehicle restraint operator that a safe condition exists. The DOK-LOK vehicle restraint is operated by
pressing push buttons on an inside control panel.
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TABLE OF CONTENTS
NOTICE TO USER
Your local RITE-HITE®representative provides a Planned Maintenance Program (P.M.P.) which can be fitted to your
specific operation. Call your local representative or the RITE-HITE®Corporation at 414-355-2600.
The RITE-HITE®products in this manual are covered by one or more of the following U.S. patents: 4,744,121;
4,819,770; 4,843,373; 4,865,507; 4,920,598; 4,995,130; 5,040,258; 5,111,546; 5,212,846; 5,271,183; 5,299,386;
5,311,628; 5,323,503; 5,375,965; 5,440,772; 5,442,825; 5,453,735; 5,531,557; 5,546,623; 5,553,987; 5,582,498;
5,664,930; 5,702,223; 5,762,459 (RE: 37,570); 5,882,167; 5,964,572; 6,010,297; 6,052,268; 6,065,172; 6.070,283;
6,074,157; 6,085,375; 6,092,970; 6,106,212; 6,116,839; 6,190,109; 6,220,809; 6,627,016; 6,238,163; 6,311,352;
6,322,310; 6,360,394; 6,368,043; 6,431,819; 6,488.464; 6,497,067; 6,499,169; 6,505,713; 6,524,053; 6,634,049;
6,654,976; 6,676,360; 6,726,432; 6,773,221 and pending U.S and foreign patent applications. RITE-HITE®, LEVEL-
RITE®, THINMANTM, SAFE-T-LIP®, HYDRACHEK®, WHEEL-LOKTM, DOK-LOK®, DUAL-DOK®, SAFE-T-STRUTTM, DOK-
COMMANDER®, JUMBOTM, HYDRA-RITETM and SAFE-T-GATE®are trademarks of RITE-HITE®Corporation.

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RITE-HITE STR-4000 DOK-LOK Owner’s Manual
SAFETY WARNINGS
LOCKOUT/TAGOUT PROCEDURES
The Occupational Safety and Health Administration requires that, in addition to posting safety warnings and
barricading the work area, 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®Corporation does not recommend any particular lockout device, but recommends the utilization of an
OSHA approved device (refer to OSHA regulation 1910.147). RITE-HITE®Corporation 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
controls, make sure that the power source has
been locked out and tagged according to OSHA
regulations and approved local electrical codes.
Figure 1 - Lockout/Tagout
This is the highest level statement. Failure to
follow the listed instructions will most likely
result in severe injury or death.
IMPORTANT is used to draw attention
to a procedure that needs to be followed to
prevent machine or property damage.
This is a statement of serious hazard. Failure to
follow the listed instructions could place the
individual at risk of serious injury or death.
The statements used with this level of
warning deal with a safe operating
procedure. If the procedure is ignored, the
possibility of personal injury may exist.

RITE-HITE STR-4000 DOK-LOK Owner’s Manual
4Pub. No. 1191 — August 2005
1. The owner should recognize the inherent danger
of the interface between dock and transport
vehicle. The owner should, therefore, train and
instruct operators in the safe use of dock
equipment in accordance with the information
provided below. The manufacturer shall publish,
provide to the initial purchaser, and make the
following information readily available to owners:
•Installation instructions
•Recommended initial and periodic inspections
procedures
•Maintenance procedures
•Operating instructions
•Descriptions or specifications for replaceable or
repairable parts
•Tables identifying the grade (slope) for all
variations of length or configuration of the dock
equipment, and
•Information identifying the maximum
uncontrolled drop encountered upon sudden
removal of support while within the working
range of the equipment.
It shall be the responsibility of the owner to verify
that the material listed in this section has been
received and that it is made available for the
instruction and training of presonnel entrusted with
the use or maintenance of the dock equipment.
2. When a transport vehicle is parked at a loading
dock, it is important that the vehicle is relatively
perpendicular to the dock face and in close contact
with at least one of the dock bumpers.
3. Nameplates, cautions, instructions, and posted
warnings shall not be obscured from the view of
operating or maintenance personnel for whom
such warnings are intended.
4. Manufacturer’s recommended periodic maintenance
and inspection procedures in effect at date of
shipment shall be followed, and written records of
the performance of these procedures should be
kept.
5. As with any piece of machinery, dock equipment
requires routine maintenance, lubrication, and
adjustments. Your local RITE-HITE®representative
offers owners the option of a Planned Maintenance
Program (P.M.P.). As part of this service, your local
RITE-HITE®representative will do all routine
maintenance, lubrication, and adjustments.
6. Dock equipment that is structurally damaged shall
be removed from service, inspected by a
manufacturer’s authorized representative, and
repaired as needed before being placed back in
service.
7. The manufacturer shall make available
replacement nameplates, caution/instruction
labels, and operating/maintenance manuals upon
request of the owner. The owner shall see that all
nameplates, caution/instruction markings or labels
are in place and legible, and that the appropriate
operating/maintenance manuals are provided to
users.
8. Modifications or alterations of dock equipment
shall be made only with written permission of the
original manufacturer. These changes shall also
satisfy all safety recommendations of the original
equipment manufacturer for the particular
application of the dock equipment.
9. When industrial trucks are driven on and off
transport vehicles during the loading and unloading
operation, the brakes on the transport vehicle shall
be applied and wheel chocks or a positive
restrainting device shall be engaged.
10. In selecting dock equipment, it is important to
consider not only present requirements but also
future plans or adverse environments.
OWNER RESPONSIBILITY

RITE-HITE STR-4000 DOK-LOK Owner’s Manual
Pub. No. 1191 — August 2005 5
DEFINITION AND FUNCTION
The STR-4000 DOK-LOK vehicle restraint is a hydraulic,
self-aligning restraint device used to secure trucks and
semi-trailers with an intact Rear Impact Guard (R.I.G.) to
the face of a loading dock. In addition this device, when
engaged, limits the vertical motion of the trailer when
loading and/or unloading. This is achieved by securing the
R.I.G. with a hydraulically positioned steel hook, while
support cylinders extend under the carriage to limit vertical
motion. This prevents forward movement of the truck/trailer
that may create an unsafe void between the face of the
dock and the rear end of the truck/trailer as a forklift travels
from the loading dock onto the trailer; or to create an
obstruction noticeable to the truck driver, should the driver
accidentally try to pull the truck/trailer away while it is being
serviced.
The proper or improper activation of the hook and support
function are monitored by:
•VISUAL CONTROL
— One set of flashing green or red lights located at the
inside of the building for the forklift operator, and one
set located outside of the building for the truck driver.
In addition to the lights, there are three instruction
signs.
• AUDIO CONTROL
— A horn will sound at the inside of the building, warning
the forklift operator if there is not R.I.G. present, or if
the engagement is improper. In this case, the trailer
must be secured by other means (wheel chokes, etc.)
prior to servicing trailer.
Prerequisite for proper barrier engagement is that the
trailer is parked firmly against a 4" (trade standard) thick
dock bumper. The activation/deactivation is solely
controlled from inside of the building by momentarily
depressing either the Lock (raise) button or the Unlock
(lower) button.
The normal mode of the hook is in the lower STORED
position, with support cylinders retracted showing a
flashing red light (trailer not secured) at the inside of the
building and a flashing green light (trailer free to move to or
away from the loading dock) at the outside of the building.
Once the trailer is parked, the dock attendant will depress
the Lock button. This will raise the hook to engage the
R.I.G. and simultaneously extend the support cylinders to
support the carriage. As soon as the R.I.G. is properly
locked with carriage supported, there will be a
simultaneous light change - the inside will change from red
to green flashing (trailer secured and supported) and the
outside will change from green to red flashing (do no move
trailer). After the service is complete, the dock attendant
will have to depress the Unlock button which then will
return the hook and support cylinders to their STORED
position.
A proper hook engagement is achieved when the hook
raises unobstructed to fully trap the horizontal cross
member of the R.I.G. Assembly. An improper hook
engagement is if the horizontal cross member of the R.I.G.
is missing, obstructed or it is bent or located so far toward
the rear axle of the trailer that it will prevent the free
passage of the hook. At this point, the trailer must be
secured by other means (example: wheel chocks) in order
to become serviceable.
The support cylinders will not be engaged
without proper hook engagement. If trailer can
not be secured, normal vertical motion of the
trailer is to be expected.

Refer to Figure 2, page 7 for the locations of the following
features:
R.I.G.
Acronym used for the Federally mandated rear impact
guard located on the rear of over the road trailers to
prevent accidental underride by automobiles.
ROLLER TRACK ASSEMBLY
Mounted to the loading dock wall to guide the carriage
assembly in a vertical plane and transmit the creep or pull
out force from a trailer to the loading dock wall.
CARRIAGE ROLLER ASSEMBLY
Comprised of a steel roller housing, a pre-lubricated needle
bearing to allow easy movement of the carriage assembly.
CARRIAGE RETURN SPRINGS AND TUBES
Bias the carriage assembly to its upward stored position
and to maintain contact with the R.I.G. while servicing a
trailer.
CARRIAGE ASSEMBLY
Sloped front provides self-positioning by the R.I.G. and
restrains the trailer once the hook has been activated by
the dock attendant.
CARRIAGE ASSEMBLY SLOPE EXTENSION
Allows trailers with lower R.I.G.’s to be serviced by the
DOK-LOK vehicle restraint.
HOOK
Entraps R.I.G. to prevent trailer from rolling/creeping away
from the dock.
HOOK CYLINDER
Provides means of moving the hook between its stored and
active positions.
SUPPORT CYLINDERS
Provides a means to support the underside of the carriage,
thus supporting the rear end of trailer.
SENSING SWITCHES, CONTROL BOX, OUTSIDE LIGHT
BOX AND SIGNAGE
Combination of these components is used to control the
STR-4000 DOK-LOK vehicle restraint and provide
audio/visual communications to the dock attendant and
trailer driver.
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RITE-HITE STR-4000 DOK-LOK Owner’s Manual
FEATURES

Pub. No. 1191 — August 2005 7
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
power unit
control
box
light
box
inside
sign
outside
signs
sensing
switch's
roller track assembly
carriage assembly
carriage roller
assembly
slope extension
return springs
and tubes
auxillary
manifold
support
cylinders
support
switch
hook
hook
cylinder
base plate
assembly
Figure 2 - STR-4000 Dok -Lok Features

8Pub. No. 1191 — August 2005
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
OPERATING PROCEDURE
Stored Position / Restraint UNLOCKED
Barrier is in the STORED position. Inside light is flashing
red alerting forklift operator unsafe condition exists.
Outside light is flashing green alerting truck driver it is
safe to back in.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
GREEN
RED
LOCK
UNLOCK
OVERRIDEHORN
3
2
1
RESTRAINT POSITION
GREEN
RED
Figure 3 - Stored Position
• Before loading or unloading a vehicle at
your loading dock while using a DOK-LOK
vehicle restraint, always visually inspect to
be sure that the barrier blocks the R.I.G.
assembly. If a condition occurs that cannot
be remedied by backing the trailer firmly
against the dock bumpers, secure the
trailer by other means.
• Be sure that the area around the R.I.G.
assembly is free of plates or other
obstructions.
• Always operate the DOK-LOK vehicle
restraint from the top of the dock.
• Inspect all restraint lights daily to make
certain they work properly.
• Perform maintenance on restraints in
accordance with Maintenance on page 19 of
this manual.
• DOK-LOK vehicle restraints should be
operated only by authorized personnel who
have read and understand the Owner’s
Manual.
• Call your local representative or RITE-HITE
at [phone] with any questions.
FAILURE TO FOLLOW THESE PROCEDURES
COULD ALLOW UNEXPECTED TRAILER /
LOADING DOCK SEPERATION RESULTING IN
DEATH OR SERIOUS INJURY!
Power Moving Components
Serious Injury Could Occur
HANDS
OFF
NO
STEP

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RITE-HITE STR-4000 DOK-LOK Owner’s Manual
Restraint LOCKED
Once the R.I.G. is entrapped by the hook and the
carriage is supported by support cylinders, a LOCKED
condition exists. Inside light is flashing green alerting
the forklift operator a safe condition exists. Outside light
is flashing red alerting truck driver not to move.
If during loading/unloading the inside light turns red and
the horn sounds, press LOCK button to secure the
R.I.G.
Outside Lights
OUTSIDE LIGHT
STATUS
RED
Inside Lights
CONTROL BOX
STATUS
GREEN
RED
LOCK
UNLOCK
OVERRIDEHORN
3
2
1
RESTRAINT POSITION
GREEN
Figure 4 - Restraint Locking
Outside Lights
OUTSIDE LIGHT
STATUS
RED
Inside Lights
CONTROL BOX
STATUS
GREEN
RED
LOCK
UNLOCK
OVERRIDEHORN
3
2
1
RESTRAINT POSITION
GREEN
Figure 5 - Restraint Locked
Visually inspect to ensure that the DOK-LOK
barrier obstructs the R.I.G. of the trailer being
serviced before operating the dock leveler.
Restraint Locking, LOCK Button Pressed
Trailer has backed into loading dock and is parked
firmly against dock bumpers. Hook rotates from stored
position to entrap the R.I.G. while the support cylinders
extend to support the carriage. Inside light is steady red
alerting the operator that an unsafe condition exists
while hook and support cylinders are in transit. Outside
light is flashing red alerting truck driver not to move.
If horn sounds, go to FAULT state, otherwise go to
Restraint LOCKED.
If trailer can not be restrainted due to a lift gate
or other obstruction that could become
damaged, go to OVERRIDE state.

10 Pub. No. 1191 — August 2005
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
Restraint UNLOCKING, UNLOCK Button
Pressed
Hook travels from the LOCKED position to the STORED
position while the support cylinders retract. Inside light
is steady red alerting the operator that an unsafe
condition exists while hook and support cylinders are in
transit. Outside light is flashing red alerting truck driver
not to move.
If horn sounds go to FAULT state, otherwise go to
STORED.
FAULT State From LOCKING State
Hook cannot entrap the R.I.G. This could be due to a
R.I.G. that is located too far toward the rear axle, bent,
obstructed or missing. Inside light is flashing red and
horn is pulsing, alerting the forklift operator that the
trailer is not locked. Outside light is flashing red alerting
the truck driver not to move. The unit will immediately
start to store itself.
If the trailer is parked firmly against the dock bumpers
go to HORN OVERRIDE state. If not, press UNLOCK to
clear the fault, have trailer back up and repeat Restraint
LOCKING.
FAULT State From UNLOCKING State
Hook cannot rotate to the STORED position. The hook
could be caught on the R.I.G. or another part of the
trailer. Inside light is flashing red and horn is pulsing,
alerting the forklift operator that the trailer is not locked.
Outside light is flashing red alerting the truck driver not
to move.
Make sure trailer is parked firmly against the dock
bumpers. If not, press LOCK to entrap R.I.G., have
trailer back up and repeat Restraint UNLOCKING.
Outside Lights
OUTSIDE LIGHT
STATUS
RED
Inside Lights
CONTROL BOX
STATUS
GREEN
RED
LOCK
UNLOCK
OVERRIDEHORN
3
2
1
RESTRAINT POSITION
GREEN
Figure 6 - Restraint Unlocking
Outside Lights
OUTSIDE LIGHT
STATUS
RED
Inside Lights
CONTROL BOX
STATUS
GREEN
RED
LOCK
UNLOCK
OVERRIDEHORN
3
2
1
RESTRAINT POSITION
GREEN
HORN
Figure 7 - Fault State

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RITE-HITE STR-4000 DOK-LOK Owner’s Manual
HORN OVERRIDE State, HORN OVERRIDE
Code Entered after Securing Trailer by
Alternate Means
An alternate means of securing the truck must be used
if the hook can not capture the rear impact guard. (i.e.
wheel chocks). Inside lights are flashing red and green
alerting the forklift operator the trailer is secured by
other means. Outside light is flashing red alerting the
truck driver not to move.
To return to STORED, enter the HORN OVERRIDE
CODE followed by the UNLOCK button.
NOTE: The unit will continue to store itself (approx. 20
seconds) after the horn has been silenced
from the FAULT STATE.
Outside Lights
OUTSIDE LIGHT
STATUS
RED
Inside Lights
CONTROL BOX
STATUS
GREEN
RED
LOCK
UNLOCK
OVERRIDEHORN
3
2
1
RESTRAINT POSITION
GREEN
Figure 8 - Horn Override State
The support cylinders will not be engaged in
HORN OVERRIDE STATE, vertical motion of
the trailer is to be expected.

NOTE: If a leveler is installed at the STR-4000
DOK-LOK vehicle restraint location, it may be
necessary to raise the leveler before performing
maintenance. Raise the leveler, insert
and secure the SAFE-T-STRUT, and
LOCKOUT/ TAGOUT the power source.
NOTE: Your local RITE-HITE®representative provides a
Planned Maintenance Program (P.M.P.) which
can be fitted to your specific operation. Call your
local representative.
DAILY
1. Remove debris around DOK-LOK vehicle restraint.
2. Verify inside and outside lights are working.
3. Replace damaged or missing light bulbs and
lenses.
4. Repair, remount, or replace outside and inside
signs as required.
5. Inspect dock bumpers. Four inches (4") of
protection is required. Worn, torn, loose or missing
bumpers must be replaced.
180 DAYS
1. Perform all Daily maintenance.
2. Grease rollers at fittings located on the top and
bottom axle. Grease hook at fitting. See figure 9
Use Mobilith SHC220 No. 2 grease (or equivalent
temperature range lithium based grease). Seven
(7) to eight (8) pumps should be used for first 180
day maintenance. Two (2) to three (3) pumps at
subsequent 180 Day maintenance intervals.
3. Inspect hydraulic hoses and power unit for signs of
leakage. Check oil fluid level, and fill with
appropriate fluid as needed.
4. Inspect pit junction and light box. They should be
rigidly mounted. If loose or damaged, inspect all
wires and wire connections.
5. Inspect switch wires from DOK-LOK vehicle
restraint to junction box. Look for kinks, crushed
areas, etc.
6. Inspect dock bumpers. Four inches (4") of
protection is required. Worn, torn, loose or missing
bumpers must be replaced.
7. Perform operational test after all maintenance
repairs and adjustments are complete.
360 DAYS
1. Perform 180 days maintenance.
2. Lubricate pivots shown with SAE 30 weight oil.
See figure 9.
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RITE-HITE STR-4000 DOK-LOK Owner’s Manual
MAINTENANCE
A safe work place requires all lights and the
horn to be working properly. DO NOT use DOK-
LOK vehicle restraint if parts are broken or
missing.
When working with electrical or electronic
controls, make sure that the power source has
been locked out and tagged according to OSHA
regulations and approved local electrical codes.
Post safety warnings and barricade work area,
at dock level and at ground level, to prevent
unauthorized use of the dock pition.
Maintenance may be required more frequently
at loading docks exposed to harsh
environments (extreme climates, corrosive
chemicals, frequency of usage, etc.). Consult
RITE-HITE if these conditions exist for
accelerated maintenance requirements.
When lifting unit use a proper lifting device
(ex. crane, jack). Lifting by hand may cause
back injury.

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RITE-HITE STR-4000 DOK-LOK Owner’s Manual
L
Figure 9 - Lubrication
LUBRICATION DETAIL
SAE 30 Weight Oil
Grease
Dry Spray Lubricate
NOTE: Use a dry spray lubricate in slots and
on the outside of lower spring tubes as shown.

14 Pub. No. 1191 — August 2005
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
TROUBLESHOOTING GENERAL DIAGNOSTIC INFORMATION
Problem Probable Cause Solution
1. DOK-LOK vehicle restraint hook does a. Power source malfunction. a. Check power source including building
not raise and lights do not flash. circuit breaker, 1A and 20A fuse on the
power module.
b. Power module failure. b. Verify the appropriate motor output
LED (M1), and SOL LED is lit when the
LOCK button or UNLOCK button is
pressed.
c. Incorrect wiring. c. Verify wiring per Electrical Schematic,
page 20, 21.
2. DOK-LOK vehicle restraint lights are a. Hook needs to be lubicated. a. Lubricated hook shaft.
flashing, but hook does not raise/ b. Severed Hose. b. Replaced damaged hose as required.
lower, to full extent. c. Power module failure. c. Verify the appropriate LED is lit when
the LOCK button or UNLOCK button is
pressed.
d. No push button inputs. d. Check for defective push button board
or ribbon cable.
e. Hook Cylinder defective. e. Disconnect cylinder and check
extension / retraction without hook
attached.
f. Incorrect wiring. f. Verify wiring per Electrical Schematic,
page 20, 21.
3. DOK-LOK vehicle restraint is a. Hook Cylinder defective. a. Disconnect cylinder and check
operational but hook drops causing extension / retraction without hook
lights to change and/or horn to sound attached.
while trailer is being serviced.
4. DOK-LOK vehicle restraint hook is a. Bulbs burnt out, loose or missing. a. Check all bulbs and replace as
operational but all lights are out. required.
b. Bad Light Fuse b. Replace as required.
c. Damaged CPU module. c. If the ISG and OSR LEDs are not
flashing while in the locked position or
the ISR and OSG LEDs are not flashing
while in the UNLOCKED position,
replace the CPU module as required.
d. Incorrect wiring. d. Verify wiring per Electrical Schematic,
page 20, 21.
5. DOK-LOK vehicle restraint inside red a. Controls are in neutral state. a. Contact your local representative or
light and horn are pulsing. Outside red RITE-HITE.
light is flashing. All buttons do not
function.
6. DOK-LOK vehicle restraint horn does a. Horn is defective. a. Power horn using 12V DC power. If
not sound, but lights and hook are horn does not sound, replace as
operational. required.
7. DOK-LOK vehicle restraint hook is in a. Incorrect wiring a. Verify wiring of SW1 and SW2 at the
stored position with an inside green light. control box and outside junction box.
8. DOK-LOK vehicle restraint carriage a. Carriage binding in track. a. Check to see if roller track plate is clean
does not return to a full up position and rollers are clean, free of debris and
lubricated. Use only approved grease to
lubricate rollers.
b. Damaged roller track plate. b. Verify that the roller track plate is
straight and not damaged.
c. Broken or weak springs c. Replace as required.
d. Improperly shimmed Base Plate d. Shim and adjust as required.

Pub. No. 1191 — August 2005 15
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
SETTING HORN OVERRIDE CODE
1. Press and hold DIAGNOSTIC button until horn
chirps (approximately three seconds).
2. Enter the factory preset HORN OVERRIDE code:
1223.
3. Enter the new HORN OVERRIDE code. The code
can be one to four numbers in length.
4. Once the new code has been entered, press the
LOCK button.
5. Controls reset with new HORN OVERRIDE code
enabled.
If no buttons are pressed within a five minute period, the
controls will automatically retain the previous code. To
exit the HORN OVERRIDE code set mode at any time,
press the DIAGNOSTIC button.
If code has been forgotten, follow the above procedures
and enter a new code.
DIAGNOSTICS
Diagnostic mode may be entered while the restraint is in
any state. To enter diagnostic mode:
1. Press and hold Diagnostic / Fill Mode button until it
chirps (approximately 3 seconds).
2. Press the LOCK button.
3. Press the UNLOCK button.
4. The horn chirps and the outside light is flashing red.
The controls are in the first step of diagnostic mode.
NOTE: The outside red light will remain flashing at
all times except Step 5.
5. Start at Step 1 in the Diagnostic Table. If the
equipment Outputs do not match the table, use the
Troubleshooting section on page 14.
If no buttons are pressed within a five minute period, the
controls will automatically exit the diagnostic mode. To
exit the diagnostic mode at any time, press the
DIAGNOSTIC button.
HORN OVERRIDE CODE AND DIAGNOSTICS
Operator Action Outputs Troubleshooting
Step 1 Press LOCK - Go to Step 2 Outside red light is flashing. Check light bulb and wiring.
OSR LED is flashing. Check CPU module and 1amp fuse.
Step 2 Press UNLOCK - Go to Step 1 Inside red light is ON. Check light bulb and wiring.
Press LOCK - Go to Step 3 ISR LED is ON. Check CPU module and 1amp fuse.
Step 3 Press UNLOCK - Go to Step 2 Inside Green light is ON. Check light bulb and wiring.
Press LOCK - Go to Step 4 ISR LED is ON. Check CPU module and 1amp fuse.
Step 4 Press UNLOCK - Go to Step 3 Inside amber light is ON (if not Check light bulb and wiring.
Press LOCK - Go to Step 5 equipped, go to Step 5). Check CPU module and 1amp fuse.
ISA LED is ON.
Step 5 Press UNLOCK - Go to Step 4 Outside red light is ON. Check light bulb and wiring.
Press LOCK - Go to Step 6 OSR LED is ON. Check light bulb and wiring.
Step 6 Press UNLOCK - Go to Step 5 Outside green light is flashing. Check light bulb and wiring.
Press LOCK - Go to Step 7 OSG LED is flashing. Check CPU module and 1amp fuse.
Step 7 Press UNLOCK - Go to Step 6 Horn is ON. Check horn and wiring. Test horn
Press LOCK - Go to Step 8 applying 12V DC power.
HRN LED is ON. Check CPU module and 1amp fuse.
Step 8 Press UNLOCK - Go to Step 7 CR1 LED is ON. (If option card is not Check Option module.
Press LOCK - Go to Step 9 installed, go to Step 12).
Step 9 Press UNLOCK - Go to Step 8 CR2 LED is ON. Check Option module.
Press LOCK - Go to Step 10
Step 10 Press UNLOCK - Go to Step 9 CR3 LED is ON. Check Option module.
Press LOCK - Go to Step 11
Step 11 Press UNLOCK - Go to Step 10 Outside red light is flashing. See Step 1.
Press LOCK - Go to Step 12 OSR LED is flashing.

16 Pub. No. 1191 — August 2005
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
Steps 12 - 14 are used to test the mechanical Inputs
and Outputs of the lock (ie. motor, limit switches, etc.).
The horn will chirp when the controls enter Steps 12 -
14 to alert the operator to check the hook position. If the
hook does not move to the correct position, the horn will
double pulse and the inside red light will be ON.
Operator Action Outputs Troubleshooting
Step 12 Press LOCK - Go to Step 13. Hook is in stored position. Check motor and verify wiring.
SW1 LED is OFF. Check switch 1 and verify wiring.
SW2 LED is ON. Check switch 2 and verify wiring.
Inside red light is ON. See Step 2.
Outside red light is flashing. See Step 5.
Step 13 Press LOCK - Go to Step 14. Hook is in lower fault position. Check motor and verify wiring.
SW1 LED is OFF. Check switch 1 and verify wiring.
SW2 LED is OFF. Check switch 2 and verify wiring.
Inside red light is ON. See Step 2.
Outside red light is flashing. See Step 5.
Step 14 Press LOCK - Hook will store and Hook is in stored position. Check motor and verify wiring.
controls exit Diagnostic mode. SW1 LED is OFF. Check switch 1 and verify wiring.
SW2 LED is ON. Check switch 2 and verify wiring.
Inside red light is ON. See Step 2.
Outside red light is flashing. See Step 5.
HORN OVERRIDE CODE AND DIAGNOSTICS
CONT.

Pub. No. 1191 — August 2005 17
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
COMPONENT TESTING
Mag. Res Limit Switch Test Procedure
(SW1 & SW2)
1. Switch must be installed to test. Apply 12VDC
power to the green lead (black lead common).
2. Set multimeter to VDC scale for DC voltage test.
3. Attach voltmeter leads to white and black wires of
sensing switch. You should have:
- magnet present = 0VDC
- magent not present = 12VDC
Mech. Limit Switch Test Procedure
(SW3)
1. Set multimeter to “RX1” scale for “Continuity Test”.
2. Attach multimeter leads to white and black wires of
limit switch connector. You should have:
— plunger released — no meter reading.
— plunger depressed — a “Full Scale” meter
reading.
NOTE: The green (ground) wire of the limit switch does
not have to be tested. A continuity test lamp
may be used instead of a multimeter.
Limit Switch and Hook Position Chart
red (not used)
white
black
green
limit switch body wire harness
mounting
bolt holes
fixed guide plunger w/roller
sensing
switch
magnet
red
green black
Figure 11 - Mechanical Limit Switch
(SW3)
Figure 10 - Magnetic Resistant Limit Switch
(SW1 & SW2)
Hook
Position
Limit Switch 1
Lock
(SW1)
(Mag. Res. Switch)
Limit Switch 2
Unlock
(SW2)
(Mag. Res. Switch)
Limit Switch 3
Support
(SW3)
(Mech. Switch)
Inside
Light
Outside
Light Horn
1. Stored Off On Open Red Green Off
2. No Hook
(No Support) Off Off Open Red Red On
3. Hooked/Support On Off Closed Green Red Off
4. No Hook
(Support On) Off Off Closed Red Red On
NOTE: Limit Switch 1 (SW1) and Limit Switch 3 (SW3) are wired in series into the SW1 input on the CPU module.

18 Pub. No. 1191 — August 2005
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
SW1 = MAG RES (SW1- LOCK) + MECH (SW3 - SUPPORT) ISR = Inside Red Light
SW2 = MAG RES (SW2 - UNLOCK) ISG = Inside Green Light
LOCK PB = Lock Push Button OSR = Outside Red Light
UNLOCK PB = Unlock Push Button OSG = Outside Green Light
PB1, 2, & 3 = Horn Silence Code Push Buttons HORN = Alarm Horn
M1 = Power Unit Run
SOL1 = Hook / Support Solenoid
SOL2 = Leveler Block SOL2 + SOL3
(Combo Only)
CR1 = Green Light Interlock Output
FAULT = SW1/SW2 did not sense a safe CR2 = Unidox Output
LOCK/UNLOCK CR3 = Security System Output
T = Steady ON D = Double Pulse
F = OFF P = Pulsing/Flashing
* = TRUE when Unidox is enabled ? = Varies depending on operation
M = Lights when button is pressed
Restraint State LED Inputs LED Outputs
Stored (Unlocked) FT - - - PFFPFFFFF*T
Locking FFM- - TFPFFTTTF*T
Locked TF - - - FPPFFFTFT*T
Storing (Unlocking) FF -M- TFPFFTFTF *T
Fault FF--- PFPFPFFFF*F
Horn Silence ?? - -M PPPF FFFFT *T
SW1
SW2
LOCK PB
UNLOCK PB
PB1,2&3
ISR
ISG
OSR
OSG
HORN
SOL1
CR1
CR2
CR3
Figure 13 - LED Status Chart
SOL2 (Combo Only)
M1
COMPONENT TESTING
DOK-LOK Vehicle Restraint Motor Test
1. BAD O/L: Little or infinite ohm reading (no needle
movement) between leads. Set multimeter to ohms.
Std. readings:
Between leads M1 and COM = approx. .8 ohm
2. OPEN WINDING: Infinite ohms (no needle
movement) between leads.
3. MECHANICAL BINDING: Motor hums. Motor leads
show continuity between all windings. Shaft does not
move.
M1
COM
G
hydraulic power unit
multimeter
Figure 12 - Motor Test

Pub. No. 1191 — August 2005 19
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
VALVE BLOCK ASSEMBIES
Lower Port
to STR4
Raise Port
to STR4
WKC (SOL 3)
Leveler Ramp
Block Solenoid
WKV (SOL 2)
Leveler Lip
Block Solenoid
Leveler
Lip Out
Port
WKX (SOL 1)
Directional
Solenoid
WKV (SOL 2)
Leveler Lip
Block Solenoid
WKC (SOL 3)
Leveler Ramp
Block Solenoid
Return to
Tank Port
Leveler
Ramp Out
Port
Adjustable
Relief Valve
NOTE: LOCATED ADJACENT TO LEVELER POWER UNIT.
ONLY ON COMBINATION POWER UNITS.
Figure 15 - Combination Power Unit Valve Block Assembly
Adjustable
Relief Valve
NOTE: MOUNTED ON STR-4000 CARRIAGE.
Raise Support
Cylinder (Left)
Lower Support
Cylinder (Left)
Raise Support
Cylinder (Right)
Lower Support
Cylinder (Right)
Lower To
Power Unit
or Combo
Valve Block
Pressure To
Power Unit
or Combo
Valve Block
Hook Cylinder
Retract (HL)
Hook Cylinder
Extend (HR)
Figure 14 - Auxillary Manifold Assembly

20 Pub. No. 1191 — August 2005
RITE-HITE STR-4000 DOK-LOK Owner’s Manual
ELECTRICAL SCHEMATIC - STAND ALONE POWER UNIT
CPU
module
photoeye
inter-
connect
hydraulic
inter-
connect
raise
LEGEND
lable LED lamp
denotes field wiring
mech./
FA inter-
connect
NOTE: Use included female spade
connectors for installation.
unidox
inter-
connect
selector
switch
OFF
security
system
interface
output
unidox
inter-
connect
output
Power
Module
ON
Limit
Switch 1
Lock
Limit
Switch 2
Unlock
(SW1)
(SW2)
green
green
white
black
black
white
(4) (5) (6) (7)
Orange ISR
12 VDC, .54A
R
Green ISG
12 VDC, .54A
Red +12V
G
H
Horn
White/Black Horn -
12 VDC, 0.03A
White/Red Horn +
Diagnostic / Fill
Mode Button
Outside Light
Common
Outside Light
Green
12VDC, 2.1A
Outside Light
Red
12VDC, 2.1A
G
R
(40)
(41)
(42)
Red
Red
Yellow
White/Orange
White/Green
Black
Black
Violet
Brown
Gray
Blue
White
+ 12VDC
+ 12VDC
Ambr Lt Cntrl
OSR Sense
OSG Sense
GND
GND
HS #3
HS #2
HS #1
Lock
Unlock
12
1
PUSH BUTTON BOARD
RG
LOCK
UNLOCK
ISA2
HS #3
HS #2
HS #1
1
L1 L2 MCOM M1
SCOM
SOL1
SOL2
CR4
CR5
250v. 1 A
Fast Blow
250v. 20 A
Slow Blow
M1
SOL1
SOL2
(BLK) (WHT)
120 VAC, 0.23 AMPS
Raise Solenoid
(1) SCom
(2) Sol1
To Customer Power Supply
120v, 1PH, 60Hz, 20 Amp.
30 Amp. Rated Fused Disconnect
With 20 Amp. Dual Element Time
Delay Fusing. (Supplied By Others)
PB3
PB2
PB1
ISA
LOCK
UNLOCK OSG
OSR
ISR
ISG
HORN
SW1
SW2
OSPWR
OSG
OSR
+V1 SW1+ SW1- +V2 SW2+ SW1-
AUX1 AUX2 AUX3
AUX1+ AUX1- AUX2+ AUX2- AUX3+ AUX3-
CR3
CR2
CR1
CR3
CR2
CR1
CR3_ A
CR3_B
CR2_ A
CR2_B
CR1_ A
CR1_B
Options
module
MCom
M1
M
Motor - 1 H.P.
120v. 1Ph. 50/60 Hz.
9F.L.A.
(L1) (L2)
leveler/
overhead
door stored
interlock
green
light
interlock
output
(WH) (BLK)
Limit Switch 3
Support (SW3)
NOTES:
1. POWER SUPPLY DISCONNECT OR PROTECTION DEVICE SUPPLIED AT INSTALLATION.
2. ALL INCOMING WIRING(L1, L2) TO BE MINIMUM #12GA. 60/75 DEG. C COPPER WIRE ONLY,
INSULATED SUFFICEINTLY FOR INCOMING VOLTAGE. (SEE CHART)
3. ALL OTHER WIRING TO BE #16GA. MINIMUM 90 DEG. C COPPER WIRE,
INSULATED SUFFICEINTLY FOR INCOMING VOLTAGE.
4. CLASS 1 CONTROL CIRCUIT.
5. USE INSULATED 1/4" FEMALE SPADE CONNECTORS.
See Chart For
Wire Size
WIRE SIZE REQUIREMENTS
Wire Run Length
Wire Gauge Size
0-50’
12GA
51-100’
10GA
101-150’
8GA
(G)
Figure 16 - Electrical Schematic - Stand Alone Power Unit