RITE-HITE STR-4200 Dok-Lok User manual

Model: STR-4200
Publication: AMEN00102 2017-07-06
STR-4200™ Dok-Lok®
Stabilizing Trailer Restraint
Owner's Manual
This manual covers units: built after serial numbers: 4537070001 and up
NOTICE TO USER. . . . . . . . . . . . . . . . . . .2
SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . .6
OPERATION . . . . . . . . . . . . . . . . . . . . . . .7
Approach-Vu™ (OPTIONAL) . . . . . . . . . . .12
MAINTENANCE
Planned Maintenance. . . . . . . . . . . . . . . .14
Lubrication . . . . . . . . . . . . . . . . . . . . . . . .15
Troubleshooting . . . . . . . . . . . . . . . . . . . .15
Hydraulic. . . . . . . . . . . . . . . . . . . . . . . . . .24
ELECTRICAL
Power Board Stand Alone . . . . . . . . . . . .28
Combo Power Unit – Power Board. . . . . .29
Restraint Micro Board. . . . . . . . . . . . . . . .30
Wiring: Pedestrian-Vu. . . . . . . . . . . . . . . .32
Wiring: Approach-Vu™ . . . . . . . . . . . . . . .34
Wiring: Outside Light Box. . . . . . . . . . . . .35
PARTS
Carriage and Track. . . . . . . . . . . . . . . . . .36
Hydraulic. . . . . . . . . . . . . . . . . . . . . . . . . .38
Electrical. . . . . . . . . . . . . . . . . . . . . . . . . .40
Signs. . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Approach-Vu™ Truck Sensor. . . . . . . . . .43
WARRANTY. . . . . . . . . . . . . . . . . . . . . . .44
Language: English
The English version of this manual shall prevail over any error in,
or conicting interpretation of, any translations.

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
2 Publication: AMEN00102 2017-07-06
NOTICE TO USER
Thank you for purchasing a STR-4200™ Dok-Lok.
STR 4200 Dok-Lok vehicle restraint is an
electro-mechanical restraint device that, when properly
installed and operated, retains a secure connection
between truck and dock. Signal lights, warning horn and
signs provide instructions to 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 interior control panel.
Read and understand this manual prior to installation or
operation of this equipment.
Rite-Hite reserves the right to substitute and/or modify
parts and drawings (electrical & architectural). If separate
prints are included with the unit, they supersede the
manual.
Contact Rite-Hite Customer Support for installation help
not covered in this manual: (U.S.) 800-456-0600.
A Planned Maintenance Program (P.M.P.), customized to
your specic operation is available and recommended.
For a P.M.P., contact your local Rite-Hite representative or
Rite-Hite technical support at (U.S.) 414-355-2600.
The Rite-Hite®products in this manual are covered by one or more
of the following U.S. patents: 5882167, 6065172, 6070283, 6085375,
6092970, 6106212, 6116839, 6190109, 6276016, 6311352, 6318947,
6322310, 6360394, 6368043, 6431819, 6488464, 6524053, 6726432,
6773221, 6832403, 6880301, 7032267, 7062814, 7213285, 7216391,
7363670, 7380305, 7503089, 7533431, 7546655, 7584517, 7681271,
7823239, 7841823, 7877831, 7914042, 8006811, 8065770, 8141189,
8191194, 8286757, 8287223, 8303235, 8307956, 8443474, 8464384,
8464846, 8465245, 8497761, 8499897, 8544130, 8547234, 8590087,
8590673, 8616826, 8657551, 8662535, 8678736, 8690087, 8905198,
9010501, 9096170, 9096397, 9126775, 9139384, 9145273, 9150367,
9174811, 9227799, 9230419 and may be covered by additional pending
U.S. and foreign patent applications.
Rite-Hite®, ThinMan™, Safe-T-Lip®, Hydrachek®, Wheel-Lok™, Dok-Lok®,
Dual-Dok®, Safe-T-Strut™, Dok-Commander®, Jumbo™, Hydra-Rite™,
Safe-T-Gate®, Rite-Vu™ Hazard Recognition and Communication System,
and Smooth Transition Dok System™, are trademarks of Rite-Hite®.
FCC Compliance
NOTE: This equipment has been tested and found to comply with the
limits for a Class A digital device, pursuant to Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against
harmful interference when the equipment is operated in a commercial
environment. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with
the instruction manual, may cause harmful interference to radio
communications. Operation of this equipment in a residential area
is likely to cause harmful interference in which case the user will be
required to correct the interference at his own expense.
NOTE: Changes or modications not expressly approved by the party
responsible for compliance could void the user's authority to operate the
equipment.
This device complies with Part 15 of the FCC Rules. Operation is subject
to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received, including
interference that may cause undesirable operation.

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 3
NOTICE TO USER
Owner Responsibility
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 specications for replaceable or
repairable parts
• Tables identifying the grade (slope) for all variations
of length or conguration 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 personnel 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. In order to be entitled to the benefits of the standard
product warranty, the dock equipment must have
been properly installed, maintained and operated
within its rated capacities and/or specific design
parameters, and not otherwise abused.
10. It is recommended that trailers equipped with air
ride suspensions should remove the air from the
suspension to minimize trailer bed drop, prior to
loading or unloading.
11. 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 restraining device
shall be engaged.
12. It is recommended that an adequate stabilizing device
or devices be employed at the front of the trailer in all
cases where a trailer is being loaded or unloaded with
the trailer resting on its support legs (landing gear)
rather than a tractor fifth wheel or a converter dolly.
13. In selecting dock equipment, it is important to consider
not only present requirements but also future plans or
adverse environments.
170316

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
4 Publication: AMEN00102 2017-07-06
NOTICE TO USER
Definition and Function
The STR-4200 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 activation of the barrier and the locking
mechanism is monitored by:
• Visual Control
1 set of ashing green or red lights located at the inside
of the building for the forklift operator, and 1 set located
outside of the building for the truck driver. In addition to
the lights, there are 3 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 rmly against a 4in [102mm] (trade
standard) thick dock bumper. The activation/deactivation is
solely controlled from inside of the building by pressing 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
ashing red light (trailer not secured) at the inside of the
building and a ashing 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 ashing (trailer secured and supported) and the
outside will change from green to red ashing (DO NOT
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 too
far from rear of 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.
CAUTION
The support cylinders will not be engaged without
proper hook engagement. If trailer can not be
secured, expect normal vertical motion of the trailer.

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 5
NOTICE TO USER
Features
U
A. Hook Sensors
B. Hook Cylinder
C. Support Limit Switch
D. Auxiliary Manifold
E. Slope Extension
F. Hook Support
G. Base Plate Assembly
H. Roller Track Assembly
I. Return Springs and Tubes
J. Support Cylinders
K. Power Unit
L. Carriage Roller Assembly
M. Carriage Assembly
N. Hook
O. Outside Signs
P. Inside Sign
Q. Outside Lights
R. Control Box
Approach-Vu™ (Optional):
S. Light and Alarm
T. Truck Sensor
U. Approach-Vu Sign
O
P
Q
R
K
A
B
C
S
D
E
F
G
H
L
M
N
J
I
T
Figure 1

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
6 Publication: AMEN00102 2017-07-06
SAFETY
Safety Identifications
DANGER
Indicates a hazardous situation which, if not
avoided, will result in death or serious injury.
WARNING
Indicates a hazardous situation which, if not
avoided, could result in death or serious injury.
CAUTION
Indicates a hazardous situation which, if not
avoided, could result in minor or moderate injury.
NOTICE
Indicates a situation which can cause damage to the
equipment, personal property and/or the environment,
or cause the equipment to operate improperly.
NOTE:A note is used to inform you of important
installation, operation, or maintenance information.
Lockout Procedure
Barricade work area and post safety
warnings.
Power supply/control must:
• Be disconnected or locked in OFF
position using a lockout device
approved by local codes.
• Have signage that:
−Clearly states repairs are being made.
− Identies person responsible for lockout condition.
NOTE:Only this person should be able to remove
warnings and lockout device.
−Withstands environmental conditions (weather, wet,
and damp, etc.) and remains readable.
General
DANGER
A qualied electrician should install wiring in
accordance with local electrical codes.
Use lockout procedures to prevent death or severe
personal injury.
170619

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 7
OPERATION
WARNING
Before loading or unloading a vehicle at your
loading dock while using a Dok-Lok vehicle
restraint, always visually conrm barrier blocks
R.I.G. assembly. Secure trailer by other means, if a
condition occurs that cannot be xed by backing
trailer rmly against dock bumpers.
Area around R.I.G. assembly must be free of
plates or other obstructions.
Always operate Dok-Lok vehicle restraint from top
of dock.
Dok-Lok vehicle restraints should be operated by
authorized personnel who have read and
understand Owner’s Manual.
Contact your local Rite-Hite representative or
Rite-Hite (U.S.) 800-456-0600 with any questions.
Failure to follow these procedures could allow
unexpected trailer / loading dock separation,
resulting in death or serious injury.
WARNING
Power moving components. Serious injury could
occur.
Slip hazard: Do not use equipment
as a step.
Pinch hazard: Keep all extremities
away.

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
8 Publication: AMEN00102 2017-07-06
OPERATION
RESTRAINT DEFAULT STATUS
STATE POSITION
CONTROL BOX:
INSIDE LIGHTS, SOUND OUTSIDE LIGHTS
Restraint UNLOCKED/
STORED position.
Hook is in STORED position.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
RESTRAINT POSITION
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
RESTRAINT POSITION
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Loading or unloading is
not permitted, since R.I.G.
is not locked.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
RESTRAINT POSITION
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE"control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Green (flashing)
A vehicle may pull
into or out of loading
bay.
Restraint LOCKING
(LOCK button pressed)
• Trailer has backed into loading
dock and is parked rmly
against dock bumpers.
• Hook rotates from STORED
position to entrap R.I.G. while
support cylinders extend to
support carriage.
If horn sounds, go to FAULT State
from LOCKING State if not, go to
Restraint LOCKED.
CAUTION
If trailer can not be restrained
due to a lift gate or other
obstruction that could
become damaged, go to
HORN OVERRIDE State.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
RESTRAINT POSITION
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
RESTRAINT POSITION
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (steady)
Alerts operator that an
unsafe condition exists
while hook and support
cylinders are in transit.
Outside Lights
OUTSIDE LIGHT
STATUS
Inside Lights
CONTROL BOX
STATUS
RESTRAINT POSITION
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE"control again.Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Alerts truck driver
not to move.

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 9
OPERATION
RESTRAINT DEFAULT STATUS
STATE POSITION
CONTROL BOX:
INSIDE LIGHTS, SOUND OUTSIDE LIGHTS
Restraint LOCKED
When R.I.G. is entrapped by
hook and carriage is supported
by support cylinders, a LOCKED
condition exists.
If during loading/unloading inside
light turns red and horn sounds,
press LOCK button to secure
R.I.G.
WARNING
Visually conrm DOK‑LOK
barrier obstructs R.I.G. of
trailer being serviced, before
operating dock leveler.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Green (flashing)
Alerts operator a safe
condition exists.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE"control again.Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Alerts truck driver
not to move.
Restraint UNLOCKING
(UNLOCK button pressed)
Hook travels from LOCKED
position to STORED position
while support cylinders retract to a
STORED position.
If horn sounds go to FAULT State
from UNLOCKING State.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (steady)
Alerts operator that an
unsafe condition exists
while hook and support
cylinders are in transit.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE"control again.Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Alerts truck driver
not to move.

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
10 Publication: AMEN00102 2017-07-06
RESTRAINT DEFAULT STATUS
STATE POSITION
CONTROL BOX:
INSIDE LIGHTS, SOUND OUTSIDE LIGHTS
FAULT State from
LOCKING State
Hook cannot entrap R.I.G.
– R.I.G. could be located too
far from rear of trailer, bent,
obstructed or missing.
Unit will store itself.
If trailer is parked rmly against
dock bumpers go to HORN
OVERRIDE state. If not, press
UNLOCK to clear fault, have trailer
back up and repeat Restraint
LOCKING.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
HORN
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
HORN
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehiclemay not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Horn (pulsing)
Alerts operator that trailer
is not locked.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE"control again.Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Alerts truck driver
not to move.
FAULT State from
UNLOCKING State
Hook cannot rotate to STORED
position.
– Hook could be caught on R.I.G. or
another part of trailer.
Verify trailer is parked rmly against
dock bumpers. If not, press LOCK
to entrap R.I.G., have trailer
back up and repeat Restraint
UNLOCKING.
OPERATION

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 11
OPERATION
RESTRAINT DEFAULT STATUS
STATE POSITION
CONTROL BOX:
INSIDE LIGHTS, SOUND OUTSIDE LIGHTS
HORN OVERRIDE State
(HORN OVERRIDE code entered
after securing trailer by alternate
means)
An alternate means of securing
truck must be used if hook can not
capture R.I.G. (i.e. wheel chocks).
To return to STORED:
1. Enter HORN OVERRIDE code
NOTE:Factory preset = 1223
2. Press UNLOCK button.
NOTE:Unit will continue to store
itself (≈ 20 seconds) after horn has
been silenced from FAULT state.
DANGER
Before operating HORN
OVERRIDE, secure trailer
by other means.
CAUTION
Support cylinders will not be
engaged in HORN OVERRIDE
state. Expect vertical motion
of trailer.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
GREEN
RED
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE" control again. Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Green (flashing)
Alerts operator trailer is
secured by other means.
OUTSIDE LIGHT
STATUS
CONTROL BOX
STATUS
RESTRAINT POSITION
Outside Lights
Inside Lights
OUTSIDE LIGHTS
Checkoutside lights when
bothLEDs are o.
UNLOCK
LOCK
1
3
2
HORN OVERRIDE
DOK-LOK®
DO NOT ENTER TRAILER
ENTER TRAILER
Visually inspect before loading/
unloading vehicle. DOK-LOK
hook must secure rear impact
guard. See warnings on side
panel.
Additional warning labels,
manuals and other information
are available by calling:
1-800-456-0600
If red light is on and/or horn
sounds, DOK-LOK is not
properly engaged.
Check operation of DOK-LOK.
Vehicle may not be against dock.
R.I.G. may not be compatible.
Hook travel may be obstructed.
Before using "HORN OVERRIDE,"
secure vehicle by other means.
Reset system by engaging "HORN
OVERRIDE"control again.Then repeat
"UNLOCK
" operation.
When in "HORN OVERRIDE" mode:
Both red and green Lights flash. "LOCK" and
"UNLOCK" controls are not functional.
Horn can be silenced by engaging
"HORN OVERRIDE" control.
Before using "HORN OVERRIDE," secure
vehicle by other means prior to entering.
If horn and red light are on
after "UNLOCK" control is
pressed,hook may be held
by R.I.G.
To release hook:
Back trailer up against dock.
Repeat "UNLOCK" operation.
Red (flashing)
Alerts truck driver
not to move.

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
12 Publication: AMEN00102 2017-07-06
OPERATION
Approach-Vu™ (OPTIONAL)
WARNING
CRUSH HAZARD
• Truck operating in dock position.
• Avoid or safely leave area when lights are ashing.
• Failure to be alert can result in death or serious
injury.
CAUTION
Do not stare at operating light. Light may be
harmful to the eyes.
Truck Detection Zone
Maximum
25ft – 60ft [7.6m –18m] 0ft [0m]
Hazard Notication on Restraint
A
When a truck is detected:
• Lights will ash (A).
• Alarm located in the restraint will sound.
Truck Sensor LEDs
GREEN LED
MANUFACTURING ENGINEER
FINISH
PRODUCTS CORPORATION
REV
SHEET
TITLE
SIZE
SCALE
DWG NO
THIRD ANGLE PROJECTION
© 2010 RITE-HITE® REVISION STATUS
DRAWN BY
RESPONSIBLE ENGINEER
DO NOT SCALE DRAWING
MATERIAL
CONFIDENTIAL
ALL SHEETS ARE THE SAME
PRODUCTS CORPORATION
B0150688
1:2 1 OF 1
M. SVEUM
RITE-HITE ®
REFERENCE
WEIGHT
.X
THIS DOCUMENT IS THE PROPERTY
HEREIN IS CONFIDENTIAL. DO NOT
PRODUCTS CORPORATION.
CONSENT OF RITE-HITE®
DISCLOSE EXCEPT WITH WRITTEN
USE, REPRODUCE, COPY OR ANGLE
.XXX
.XX
TOLERANCES:
A
B
4321
B
A
1
2
34
OF RITE-HITE® PRODUCTS
DIMENSIONS ARE IN INCHES.
UNLESS OTHERWISE SPECIFIED
CORPORATION. SUBJECT MATTER
= .120
= .060
= .030
= 2.0
NOT RELEASED
GREEN LED RED LED
REV DATE DESCRIPTION ECN APPROVED BY
REVISION HISTORY
Green Red
STATE LEDS
Start-Up Red/Green (Flashing)
Ready Green (Steady)
Detects Truck Red (Flashing)
False Detection Green or Red/Green (Flashing)
Figure 2
Figure 3
Figure 4

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 13
MAINTENANCE
!DANGER
When working with electrical or electronic
controls, make sure that power source has been
locked out and tagged according to approved
local electrical codes.
Post safety warnings and barricade work area, at
dock level and approach level, to prevent
unauthorized use of dock position.
WARNING
A safe work place requires all lights and horn to
be working properly. DO NOT use Dok-Lok vehicle
restraint if parts are broken or missing.
CAUTION
When lifting unit use a proper lifting device (crane,
jack). Lifting by hand may cause back injury.
NOTICE
Contact Rite-Hite if loading docks are exposed to
harsh environments (extreme climates, corrosive
chemicals, high usage, etc.). More frequent
maintenance may be required.
A Planned Maintenance Program (P.M.P.), customized to
your specic operation is available and recommended. For
a P.M.P., contact your local Rite-Hite representative.
NOTE:If a leveler is installed at Dok-Lok vehicle restraint
location, it may be necessary to raise leveler before
performing maintenance.
!DANGER
B
A
When working under dock leveler platform or lip:
1. Install Safe-T-Strut™ with the assistance of
another person.
• Raise leveler until platform reaches its highest
position and lip extends. Maintain this position.
• (A) Have assistant insert the smaller end of the
Safe-T-Strut™ through hole in the middle of
leveler lip and place strut’s wider open end over
the base located on leveler’s front frame (B).
• Align the holes on the base and Safe-T-Strut™
so leveler may be secured with retaining pin
and safety clip.
• Release the pushbutton on powered levelers
allowing the Safe-T-Strut™ to rest on the
underside of lip.
NOTE:If you are unable to install the
maintenance support, contact your Rite-Hite
Service Representative or Rite-Hite Customer
Service at 1-414-355-2600.
2. Lockout and tag power supply.
• Turn off power to control box.
• Lock out and tag the main power source
• Barricade leveler at dock and approach levels
to prevent unauthorized use.
Safe-T-Strut™ removal:
• Have an assistant raise leveler to its highest
position with lip fully extended.
• Release safety clip and remove retaining pin.
• Lift the support off base.
• Return Safe-T-Strut™ to it's storage position.

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
14 Publication: AMEN00102 2017-07-06
MAINTENANCE
Planned Maintenance
P.M. IN DAYS
INSPECT AND PERFORM:
# 1 180 360
1 Remove debris around Dok-Lok vehicle restraint
2 Verify horns, 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. 4in [102mm] of protection is required. Worn, torn, loose or missing bumpers must be replaced.
6 –  
See "Figure 5". Grease rollers at ttings located on top and bottom axle. Grease hook and support cylinders at ttings.
Use Mobilith SHC220 No. 2 grease (or equivalent temperature range lithium based grease).
1st 180 days: 7–8 pumps
180 Day intervals (after rst 180): 2–3 pumps
Note: Items that use SAE 30 weight oil lubricant only require lubrication every 360 Days.
7 –   Check that all concrete anchor bolts are torqued to 60 ft-lbs..
8 –   Inspect hydraulic hoses and power unit for signs of leakage. Check oil uid level, and ll with appropriate uid as needed.
9 –   Inspect outside junction and light box. They should be securely mounted. If loose or damaged, inspect all wires and wire
connections.
10 –   Inspect switch wires from Dok-Lok vehicle restraint to junction box. Look for kinks, crushed areas, etc.
11 –  
Inspect all conduit boxes, control boxes and electrical connections for damage. Repair or replace if worn or damaged..
If control box has evidence of condensation:
a. Inspect conduit. Conduit should be routed to enter through bottom or side of enclosure. A drip leg may be needed if
conduit is filling with water.
b. Inspect seal on cover of enclosure. Seal should be securely adhered to cover with no signs of peeling or bubbling.
Repair or replace if worn or damaged.
c. For non-metallic enclosures, breather vent (part number 122130) may be installed. Vent is NEMA 4X and will not
change environmental rating of control box.
12 –   Perform operational test after all maintenance repairs and adjustments are complete.
13 – – Check and tighten control box mounting hardware

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 15
MAINTENANCE
Lubrication
SAE 30 Weight Oil
Grease:
Use Mobilith SHC220 No. 2 grease
(or equivalent temperature range lithium
based grease)
Dry Spray Lubricate:
Use in slots and on outside of lower
spring tubes, as shown.
Troubleshooting
Normal Restraint Function in Fault State
If STR faults immediately, LOCKED State was never
achieved:
• All cylinders retract (unit stores) and inside RED light
and HORN.
• Outside RED light, inside RED light and HORN.
If STR faults after being in LOCKED State:
• All cylinders remain extended, hook stays up, but
support cylinders do not function.
• Outside RED light, inside RED light and HORN
Figure 5

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
16 Publication: AMEN00102 2017-07-06
MAINTENANCE
Troubleshooting Continued
PROBLEM PROBABLE CAUSE REMEDY
1. Unit faults after LOCK
button is pressed, never
gets an inside GREEN light.
Damage or missing rear impact
guard.
Restrain trailer by alternate means, place system in HORN-OVERRIDE
state.
Truck not backed in straight or tight
against bumpers.
Re-position trailer.
Hydraulic system malfunction. Verify power unit runs for ~25sec. and cylinders fully extend. If not,
contact Rite-Hite.
Sensor issue. Verify sensor operation and adjustment; see sensor testing and
adjustment procedure.
2. Unit locks (gets inside
GREEN light) then faults
when a forklift enters or
leaves trailer.
Trailer is not tight against bumpers. Re-position trailer.
Damaged rear impact guard. Verify condition of rear impact guard, if damaged, restrain trailer by
alternate means and place system in HORN-OVERRIDE state.
Sensor(s) out of adjustment. Verify sensor adjustment; see sensor testing and adjustment procedure.
3. Hook does not raise and
lights do not flash.
Power source malfunction. Check power source including building circuit breaker, 1.5A and 15A fuses
on power module.
Power module failure. Verify appropriate motor output LED (M1), and SOL LED is lit when LOCK
button or UNLOCK button is pressed.
Incorrect wiring. Verify wiring per electrical schematic.
4. Lights are flashing, but
hook does not raise/lower.
Hook needs to be lubricated. Lubricate hook shaft.
Severed hose. Replace damaged hose as required.
Sensor(s) out of adjustment. Verify appropriate LED is lit when LOCK button or UNLOCK button is
pressed.
Check for defective push button board or ribbon cable.
Disconnect cylinder and check extension / retraction without hook
attached.
Verify wiring per electrical schematic.
5. Is operational but hook
drops causing lights to
change and/or horn to
sound while trailer is being
serviced.
Hook cylinder defective. Disconnect cylinder and check extension / retraction without hook
attached.
6. Hook is operational but all
lights are out.
Bulbs burnt out, loose or missing. Check all bulbs and replace as required.
Damaged circuit board. If ISG and OSR LEDs are not ashing while in locked position or ISR and
OSG LEDs are not ashing while in UNLOCKED position, replace circuit
board.
Incorrect wiring. Verify wiring per electrical schematic.
7. Control box horn does not
sound, but lights and hook
are operational.
Horn defective. Power horn using 12V DC power. If horn does not sound, replace as
required.
8. Hook is in stored position
with and inside green light.
Incorrect wiring. Verify wiring of SW1 and SW2 at control box and outside junction box.
9. Carriage does not return to
a full up position.
Carriage binding in track. Check to see if roller track plate is clean and rollers are clean, free of
debris and lubricated. Use only approved grease.
Damaged roller track plate. Verify that roller track plate is straight and not damaged.
Broken or weak springs. Replace as required.
Improperly shimmed Base Plate. Shim and adjust as required.

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 17
MAINTENANCE
Troubleshooting Continued
Sensor Adjustments
Position support limit switch
so switch is activated when
cylinder rod is extended and
resting in support pocket.
NOTE:
- Adjusting switch too high could
result in damage to switch.
- A 3/4" deep well socket or section
of 1" OD round works well to
simulate engaged cylinder rod.
.34 (+.06)
(-.00)
Support Limit
Switch (SW3)
Unlock Sensor
Lock Sensor
Limit Switch Flag
Lock Sensor
(SW1)
Unlock
Sensor
(SW2)
Support Limit Switch
(SW3)
Limit Switch Flag
.34 (+.06)
(-.00)
Position support limit switch
so switch is activated when
cylinder rod is extended and
resting in support pocket.
NOTE:
- Adjusting switch too high could
result in damage to switch.
- A 3/4" deep well socket or section
of 1" OD round works well to
simulate engaged cylinder rod.
.34 (+.06)
(-.00)
Support Limit
Switch (SW3)
Unlock Sensor
Lock Sensor
Limit Switch Flag
Position support limit switch so
switch is activated when cylinder
rod is extended and resting in
support pocket.
Use a spacer (e.g. 3/4in deep well socket or section of 1in
[25mm] OD round) to test location of cylinder rod when it
is engaged.
Adjusting switch too high could result in damage to switch.
Figure 6

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
18 Publication: AMEN00102 2017-07-06
MAINTENANCE
Troubleshooting Continued
Component Testing – Switches/Sensors
1. Set multimeter to “RX1” scale for “Continuity Test”.
2. Attach multimeter leads to white and black wires of
switch connector:
Magnetic Sensor (SW1,SW2)
No magnet present = No meter reading
Magnet present = a "Full Scale" meter reading
Mechanical Limit Switch (SW3)
Plunger released = No meter reading
Plunger depressed = a "Full Scale" meter reading
sensing
switch
magnet
white
black
Magnet
Sensing
Switch
White
Black red (not used)
white
black
green
limit switch body
wire harness
mounting
bolt holes
fixed guide
plunger w/roller
Fixed Guide Plunger with Roller
Mounting
Bolt Holes
Wire Harness
Limit Switch Body
Green
Black
White Red (not used)
• Green (ground) wire of limit switch does not have to be
tested. A continuity test lamp may be used instead of a
multimeter.
• Sensor 1 (SW1) and Limit Switch 3 (SW3) are wired in series
into SW1 input on micro control board.
Limit Switch and Hook Positions
HOOK POSITION
LOCK SENSOR
(SW1)
UNLOCK SENSOR
(SW2)
SUPPORT LIMIT SWITCH
(SW3)
INSIDE
LIGHT
OUTSIDE
LIGHT
CONTROL BOX
HORN
1. Stored Off On Open / Released Red Green Off
2. No Hook (No Support) Off Off Open / Released Red Red On
3. Hooked (90° Support On) On Off Closed / Depressed Green Red Off
4. No Hook (Support On) Off Off Closed / Depressed Red Red On
Figure 7

Rite-Hite®Owner's Manual STR-4200™ Dok-Lok®
Publication: AMEN00102 2017-07-06 19
MAINTENANCE
Troubleshooting Continued
Component Testing – Vehicle Restraint Motor
Hydraulic Power Unit
M1
COM
G
hydraulic power unit
multimeter
Multimeter
COM
M1
G
1. Shorted: Set multimeter to ohms.
• Take readings between leads M1 to ground/motor
casing and COM to ground/motor casing.
• Reading should be Innite (0) ohms
(no needle movement).
• Any reading indicates bad motor windings.
2. Mechanical Binding:
• Motor hums.
• Motor leads show continuity between all windings.
• Shaft does not move.
Figure 8

STR-4200™ Dok-Lok®Owner's Manual Rite-Hite®
20 Publication: AMEN00102 2017-07-06
MAINTENANCE
Troubleshooting Continued
LED Status Chart
? = Varies (per operation) A = Alternating D = Double fast pulsing / ashing F = Off ITL = Interlock input on K = Continuous slow chirp M = Lights when button pressed P = Pulsing / Flashing
(set to steady using DIP switches)
T = Steady On
MICRO CONTROL BOARD POWER BOARD INPUTS OUTPUTS FIELD PUSH BUTTONS 12VDC RELAY 115/230VAC
Dok-Lok Limit Switch 1 [SW1]
Dok-Lok Limit Switch 2 [SW2]
Unlock Interlock [UNLK ITL]
Lock
Unlock
Horn Silenlence (1/2/3)
Inside Red Light [ISR]
Inside Green Light [ISG]
Corner-Vu Red Light [CVU RD]
Corner-Vu Green Light [CVU GRN]
Leveler-Vu Red Light [LVU RD]
Leveler-Vu Green Light [L-VU GRN]
Outside Red Light [OSR]
Outside Green Light [OSG]
Dok-Lok Horn [HORN]
Leveler Motor Contactor
[Combined Power Unit Only]
Restraint Overload LED [YELLOW]
K1 - Green Light Interlock
K2 - Security System Interface
[IF EQUIPPED]
K2 - Combined Power Unit
[IF EQUIPPED]
Motor Ouptut #1 [M1/RUN]
Solenoid #1 (RSOL1/RAISE)
Solenoid #2 (RSOL2/DIVERT)
[Combined Power Unit Only]
12VDC Power Supply OK
TERMINAL BLOCK NO. J13.1 J13.2 J14.3 Membrane J7.16 J7.17 J12.1 J12.2 J12.3 J12.4 J11.2 J11.1 J7.19 J15.1 N/A J9.3 J10.3 J10.3 J5.4 J7.3 J7.2 J2.1-6 POWER BOARD LEDS ––––––––––––––––––––LD2LD10LD9LD7
MICRO CONTROL BOARD LEDS LD20 LD23 LD30 LD52 LD17 LD19 LD11 LD13 LD18 LD12 LD49 LD48 LD15 LD42 LD50 LD9 LD10 LD10 LD1 LD8 LD6 –
NO.
01.01.00
State/Sequence No.
Locked State T F ? – – – F P F P F P P F F F F T T F F T F T
01.01.01 Locking Sequence T F ? M – – T F P F P F P F F T F F T T T T T T 01.02.00 Unlocked State F T ? – – – P F P F P F F P F F F F T F F F F T 01.02.01 Unlocking Sequence F F ITL – M – T F P F P F P F F T F F T T T F T T
01.04.00 Fault State ? ? ? – – – P F P F P F P F P F F F F F F F F T 01.04.01 Fault Silenced State ? ? ? – – M A A A P F F F F T T F F F F T 01.11.00 Overload Fault State ? ? ? – – – P F P F P F P F K F T F F F F F F T
RESET PROCEDURE: Motor Overload Fault State (Amber LED LD50 is illuminated and the Dok-Lok horn is slowly chirping.) 1. Press and hold Horn Silence Button (3-Button System)/Horn Silence #2 Button (5-Button System) until Horn Chirps (≈ 5 Seconds). Or 2. Press and Release Restraint O/L Button on Micro Controller Board. When the motor overload has been reset, the Yellow LD50 LED will turn off and normal operation resumes. If Dok-Lok motor does not run after resetting the overload, check Motor Fuse 10FU1.