Johnson JRT300-RDHV-S User manual

©2023 Johnson Level & Tool 1
4000' Dual Slope Rotary Laser
Model No. JRT300-RDHV-S
Model No. JRT300-RDHV-K
Instruction Manual
Congratulations on your choice of this 4000' Dual Slope Rotary
Laser Level. We suggest you read this instruction manual thoroughly
before using the instrument. Save this instruction manual for future
use.
This is a Class 3R laser tool and is manufactured to comply with
CRF21, parts 1040.10 and 1040.11 as well as international safety rule
IEC285.

2 ©2023 Johnson Level & Tool
Table of Contents
1. Kit Contents
2. Safety Instructions
3. Getting Started
4. Warning Labels
5. Parts/Components
6. Operation Instructions
7. Accuracy Check
8. Specifications
9. Care and Handling
10. Product Warranty &
Registration
11. Accessories
12. Trouble Shooting
1. Kit Contents
Description for Model JRT300-RDHV-S Qty.
4000' Dual Slope Rotary Laser 1
Alkaline Battery Compartment (batteries not included) 2
Lithium-ion Batteries 2
Detector with Clamp and 2 “AAA” Alkaline Batteries 1
Remote with 2 “AAA” Alkaline Batteries 1
Magnetic Target 1
Type C, USB adapter/charger 1
8' Grade Rod 1
Tripod 1
Hard-Shell Carrying Case 1
Description for Model JRT300-RDHV-K Qty.
4000' Dual Slope Rotary Laser 1
Alkaline Battery Compartment (batteries not included) 2
Lithium-ion Batteries 2
Detector with Clamp and 2 “AAA” Alkaline Batteries 1
Remote with 2 “AAA” Alkaline Batteries 1
Magnetic Target 1
Type C, USB adapter/charger 1
Hard-Shell Carrying Case 1

©2023 Johnson Level & Tool 3
2. Safety Instructions
CAUTION!
Class 3R Laser Product
Max. Power Output: ≤5mW
Wavelength: 630-650nm
THIS TOOL EMITS LASER RADIATION.
DO NOT STARE INTO BEAM.
AVOID DIRECT EYE EXPOSURE.
ATTENTION IMPORTANT
• Read all instructions prior to operating this laser tool. Do not remove
any labels from tool.
• Do not stare directly at the laser beam.
• Do not project the laser beam directly into the eyes of others.
• Do not set up laser tool at eye level or operate the tool near a reflective
surface as the laser beam could be projected into your eyes or into the
eyes of others.
• Do not place the laser tool in a manner that may cause someone to
unintentionally look into the laser beam. Serious eye injury may result.
• Do not operate the tool in explosive environments, i.e. in the presence
of gases or flammable liquids.
• Keep the laser tool out of the reach of children and other untrained
persons.
• Do not attempt to view the laser beam through optical tools such as
telescopes as serious eye injury may result.
• Always turn the laser tool off when not in use or left unattended for a
period of time.

4 ©2023 Johnson Level & Tool
3. Getting Started
IMPORTANT: It is the responsibility of the user to verify the
calibration of the instrument before each use. See section 7.
How to Charge Lithium-ion Batteries
The rotary laser unit is shipped with two Lithium-ion (Li-ion)
batteries installed but not charged. Li-ion batteries can be charged
either installed or external to the unit. Follow the steps below to
charge the batteries.
How to Charge Lithium-ion Batteries Inside the Unit
1. Slide open the battery recharge
port on the front of the rotary laser.
(Figure 1)
RL-RHV
RPMRPM
X
Y
X
X
Y
MAN
Figure 1
2. Connect the Type C, USB adapter/
charger to the rotary laser recharge
port. (Figure 2)
3. Connect the opposite end of charging
cable to a power source and note
that a green light next to the charging
port lights up. Charge time is typically
5 hours.
4. When charged using this method,
the battery charge is indicated by
LED light "b". See Operating Panel
Overview.
Green = ≥30%
Red = 10% ≤≥30%
Flashing Red = ≤10%
RL-RHV
RPMRPM
X
Y
X
X
Y
MAN
Figure 2

©2023 Johnson Level & Tool 5
5. Disconnect the Type C, USB adapter/
charger and close the recharge port.
(Figure 3)
RL-RHV
RPMRPM
X
Y
X
X
Y
MAN
Figure 3
How to Charge Lithium-ion Batteries Outside the Unit
1. Push in and turn the battery lock
knob clockwise to the “Unlock”
position. (Figure 4)
Figure 4
2. Remove battery compartment from
rotary laser. (Figure 5)
3. Remove each battery case from the
battery compartment.
Figure 5

6 ©2023 Johnson Level & Tool
4. Check the fuel gauge status
of the Li-ion battery. Press the
micro switch on the battery.
Note which LEDs light up. See
the table below to determine
the power status of the battery.
The LEDs will turn off after
three seconds. (Figure 6)
LED1
LED2
LED3
Micro
Switch
Figure 6
Fuel Gauge LED1 LED2 LED3
Volt of battery < 3.5V ON OFF OFF
3.5V ≤Volt of battery <3.8V ON ON OFF
3.8V ≤Volt of battery ON ON ON
5. Connect the Type C, USB adapter/
charger to battery charging port
located on the front of the battery.
(Figure 7)
6. Connect the opposite end of charging
cable to a power source and note
that battery charging LEDs light up.
When all three are lit, the battery is
fully charged. Charge time is typically
5 hours. See the table below to
determine the charging status of the
battery.
Figure 7
Fuel Gauge LED1 LED2 LED3
Volt of battery < 3.6V Flashing OFF OFF
3.6V ≤Volt of battery <3.9V ON Flashing OFF
3.9V ≤Volt of battery ON ON Flashing
4.165V ≤Volt of battery <4.235
(fully charged)
ON ON ON

©2023 Johnson Level & Tool 7
7. Reinsert the battery cases into the
battery compartment. Be sure the end
with the openings is aligned with the
opening on the rear of the battery
compartment. (Figure 8)
Figure 8
8. Reinsert the battery compartment into
the rotary laser. (Figure 9)
Figure 9
9. Push in and turn the battery lock knob
counterclockwise to the “Lock”
position to lock the battery cover.
(Figure 10)
Figure 10
How to Install or Replace Alkaline Batteries
NOTE: Always check that the battery compartment lock knob is in
the “Unlock” position before removing and/or replacing batteries.
1. Push in and turn the battery lock
knob clockwise to the “Unlock”
position. (Figure 11)
Figure 11

8 ©2023 Johnson Level & Tool
2. Remove battery compartment from
rotary laser. (Figure 12)
3. Remove each battery case from the
battery compartment.
Figure 12
4. Slide the covers off the battery
cases and insert three “AA” alkaline
batteries into each case according
to the polarity illustrated inside.
(Figure 13)
Figure 13
5. Reinstall the covers and reinsert
the battery cases into the battery
compartment. Be sure the end with
the openings is aligned with the
opening on the rear of the battery
compartment. (Figure 14)
Figure 14
6. Reinsert the battery compartment into
the rotary laser. (Figure 15)
Figure 15

©2023 Johnson Level & Tool 9
7. Push in and turn the battery lock knob
counterclockwise to the “Lock”
position to lock the battery cover.
(Figure 16)
Figure 16
How to Use the Type C, USB adapter/charger
If no batteries (Lithium-ion or alkaline) are available, you can
connect a Type C, USB adapter/charger power cord or power bank
to the rotary laser using the battery recharge port, and connect the
opposite end of charging cable to a power source.

10 ©2023 Johnson Level & Tool
Operating Panel Overview
RL-RHV
RPMRPM
X
Y
XX
Y
MAN
4
6
a
2
3
5
c
d
e
7f
g
1b
Push Buttons
1. ON/OFF button
2. Rotation Speed Selection button
(600rpm-1200rpm-0-100rpm-300rpm)
3. Line Operation and Length Operation button (15°, 30°, 60°, 0°)
4. Shock Warning Indicator button
5. Dual-Axis Slope Operation button
6. Upper/Clockwise Direction button
7. Lower/Counterclockwise Direction button

©2023 Johnson Level & Tool 11
LED Lights
LED Color Flashing Steady Off
aGreen Shock warning
activated
Shock warning
deactivated
Red Shock Alarm
bGreen Battery power
≥30%
Red Battery power
≤10%
Battery power
between 30% and
10%
cGreen Auto adjusting Auto adjusting
finished
Red MORE THAN 5°
out of level
dGreen Scan Mode
selected
eGreen Manual Mode
activated (Press
Dual-Axis Slope
Operation button
for three seconds)
fGreen X axis leveling
adjustment
activated (Press
Dual-Axis Slope
Operation
button once)
X axis adjustments
complete
X axis leveling
adjustment
deactivated
Red MORE THAN 5°
out of level
gGreen Y axis leveling
adjustment
activated (Press
Dual-Axis Slope
Operation
button twice)
Y axis adjustments
complete
Y axis leveling
adjustment
deactivated
Red MORE THAN 5°
out of level

12 ©2023 Johnson Level & Tool
4. Warning Labels
Laser radiation. Do not stare into
beam. Class 3R laser product.
Complies with 21 CFR 1040.10 and
1040.11 except for deviations
pursuant to laser 50, 6/24/2007
Radiación láser. No mire al rayo. Producto láser de
clase 3R. Cumple con las normas 21 CFR 1040.10 y
1040.11, excepto por las desviaciones conforme al
aviso para láseres 50 del 24 de junio de 2007.
Rayonnement laser. Ne regardez pas directe-ment
dans le faisceau. Produit laser de classe 3R.
Conforme à 21 CFR 1040.10 et 1040.11, sauf pour
les écarts suivant l´avis laser 50, 24/6/2007
©2023 JOHNSON LEVEL & TOOL MFG. CO., INC.
MEQUON, WI 53092
JRT300-RDHV
3*1.5V(AA) or 3.6V Li-ion 5200mAh
or TypeC 5V, 2A
Class 3R，<5mW; 630-650nm
MADE IN CHINA
Warning
Label Serial
Number
Model Number

©2023 Johnson Level & Tool 13
5. Parts/Components
Battery Recharge Port
Keypad
Hand Grips
X-Calibration
Guide
Laser Line Output
Window
Y-Calibration
Guide
Rotating Laser
Output Window
5/8" - 11 Screw Thread
Battery Lock
and Cover 5/8" - 11 Screw Thread
and Laser Output
Window

14 ©2023 Johnson Level & Tool
6. Operation Instructions
IMPORTANT: It is the responsibility of the user to verify the
calibration of the instrument before each use. See section 7.
Using the Rotary Laser
1. Horizontal or Vertical Position
The Johnson Rotary Laser can be used in either a horizontal or
vertical orientation, depending on your needs.
Horizontal Laser Beam Position
Place the rotary laser in an upright
position, either on a stable, flat
surface, or mount it to a tripod with a
5/8"-11 threaded screw. (Figure 17)
Figure 17
Vertical Laser Beam Position
Place the rotary laser on the side
opposite the control panel, either on a
stable, flat surface, or mount it to a tripod
with a 5/8"-11 threaded screw. (Figure 18)
Figure 18

©2023 Johnson Level & Tool 15
2. Automatic Mode
This feature enables the automatic leveling function of the rotary
laser.
IMPORTANT: It is best practice to ensure the Shock Warning
feature is engaged when the unit is in Automatic Mode. This will
prevent the unit from re-leveling if the unit is bumped, jarred, or
in any way moved from its original position while turned on. If the
unit's position does change, verify the unit's position (for example,
height) to the potentially changed conditions. It is best to turn the
unit off before you move it.
1. Press the button to power on/off the rotary laser. The rotary
laser enters automatic leveling mode by default. During leveling,
indicator “c” flashes green. After leveling, indicator “c” is steady
green. The rotary laser will rotate at 600 rpm.
Power/Battery LED: Steady green LED indicates power is on
and battery power is greater than 30%.
Steady red LED indicates power is on and
battery power is between 30% and 10%.
Flashing red LED indicates power is on
and less than 10%. Charge or change the
batteries.
Extinguished LED indicates power is off or
battery has been depleted
2. If the rotary laser is placed out of the working angle (5°),
indicator “c” flashes red. At the same time the X LED and/or
the Y LED flashes red. These indicate the direction that is out of
working angle. Adjust the rotating laser position as directed by
the indicator in the corresponding direction until the X and/or Y
LED turns off and only the “c” LED flashes. Continue leveling the
unit until indicator “c” is steady green.

16 ©2023 Johnson Level & Tool
3. Rotation Speed Mode
This feature changes the rotating speed of the laser.
Press the RPMRPM button to change the rotating speed from the default
600 rpm to 1200 rpm, 0 rpm, 100 rpm, or 300 rpm. Each time
this button is pressed, the rotating speed cycles through the rpm
settings.
NOTE:
• When starting the unit, the laser will rotate at 600 rpm.
• A lower speed (0 - 300 rpm) is recommended for indoor use to
give the best beam visibility.
• A higher speed (600 - 1200 rpm) is recommended when used with
a detector.
4. Point/Line Segment Mode (Scan Mode)
This feature changes the 360° rotating laser to either a line segment
laser or a single laser point.
1. To change from a 360° rotating laser to a laser point or line,
press the button. This can be done when the rotary laser
is working in either Automatic or Manual mode. Each time this
button is pressed, the laser will cycle successively from 15°, 30°,
60°, or 0°.
2. In Point/Line Segment mode, press button to adjust the
position of the laser line clockwise or press button to adjust
the position of the laser line counterclockwise.
3. Press the RPMRPM button to exit Point/Line Segment Mode.

©2023 Johnson Level & Tool 17
5. Shock-Warning Function (Automatic Mode only)
This feature alerts if the unit has changed position while in
Automatic mode. This may be the result of something striking the
unit, strong winds shifting the unit, or shaking on the ground. It
prevents the rotary laser from auto leveling after it changes height,
thus preventing vertical height errors.
1. Press button to start the Auto Detect Shock function. The
LED next to the button will illuminate green. If the rotary laser
is affected by wind, is moved or tilted, the rotary laser will
automatically stop rotating, the laser point will flash, and the LED
next to the button will flash red.
2. To clear the alarm, ensure the rotary laser is back in position, and
press the button. The flashing red LED indicator turns off. The
unit will enter the automatic mode again to self-level. Reconfirm
the leveling height.
3. Press the button once to start or remove the shockproof
function.
6. Manual Mode Function
This feature allows the rotary laser unit to be placed in an angled
position. It can be used with the unit in either Rotation mode
or Point/Line Segment mode. When the unit is in Manual mode,
accuracy of the device is based on the skill and accuracy of the end
user. When used in this mode, specified accuracy is not applicable.
1. Press the X
Y
MAN button for three seconds to enter Manual mode.
The LED “e” will illuminate a steady green. The automatic leveling
mode is off, and the rotary laser can be placed at any angle.
2. Press the X
Y
MAN button for three seconds to exit Manual mode and
return to Automatic mode.

18 ©2023 Johnson Level & Tool
7. Slope Mode Function
This feature allows the rotary laser to adjust the pitch of the laser
line. Follow the markings on the housing of your unit, as you are
looking at the front of it.
1. Place the rotating laser in a horizontal or vertical position. Press
the X
Y
MAN button for three seconds to enter Manual mode. The LED
“e” will illuminate a steady green.
2. To change the X direction (right and left): press the X
Y
MAN button.
The X LED flashes green. Press the button or button to
adjust the laser angle right or left respectively. Each adjustment
is 1 mm at 30 meters. Hold the button for faster adjustments.
When the laser beam reaches the desired position, press the X
Y
MAN
button. The X LED will illuminate steady green, and the Y LED
will flash green. Press the X
Y
MAN button again to finish X direction
adjustments. The top two LED lights will illuminate steady green.
NOTE: If the X-axis tilt is greater than 5°, the X LED light flashes red.
3. To change the Y direction (front and back): press the X
Y
MAN button.
The X LED flashes green. Press the X
Y
MAN button again. The Y LED
flashes green. Press the button or button to adjust the
laser angle front or back respectively. Each adjustment is 1 mm
at 30 meters. Hold the button for faster adjustments. When the
laser beam reaches the desired position, press the X
Y
MAN button to
finish Y direction adjustments. The first and third LED lights will
illuminate steady green.
NOTE: If the Y-axis tilt is greater than 5°, the Y LED light flashes red.
4. To change the both the X and Y directions: press the X
Y
MAN button.
The X LED flashes green. Press the button or button to
adjust the laser angle right or left respectively. Press the X
Y
MAN
button again. The Y LED flashes green. Press the button or
button to adjust the laser angle front or back respectively. When
the laser beam reaches the desired position, press the X
Y
MAN button
to finish adjustments. All three LED lights will illuminate steady
green.

©2023 Johnson Level & Tool 19
Using the Remote
1. Technical Specifications
Power 2 “AAA” Batteries
Steady red LED indicates power is on and
battery power is between 30% and 10%
Flashing red LED indicates power is on
and less than 10%. Charge or change the
batteries.
Extinguished LED indicates power is off.
2. Operating Panel Overview
RPM
X
Y
XX
Y
MAN
5.
6.
4.
3.
2.1.
Push Buttons
1. Lower/Counterclockwise Direction
button
2. Upper/Clockwise Direction button
3. Rotation Speed Selection button
(600rpm-1200rpm-0-100rpm-300rpm)
4. Line Operation and Length Operation
button (15°, 30°, 60°, 0°)
5. Shock Warning Indicator button
6. Dual-Axis Slope Operation button
7.
7. Battery Compartment

20 ©2023 Johnson Level & Tool
3. Operation
To install batteries into the remote, open the battery compartment
and insert two “AAA” alkaline batteries according to the polarity
illustrated inside.
NOTE: Take the batteries out when the unit is not in use for a long
time.
Press any button on the remote to turn it on.
The buttons on the remote work the same as the buttons on the
rotary laser.
4. Maintenance
• Keep the remote clean. If unit becomes dusty, use a clean cloth to
gently wipe it clean.
• Avoid knocking the unit over or allowing it to fall to the ground.
• Although the remote is rain resistant, avoid submerging the unit
in water or other liquids. If unit comes into contact with water or
other liquids, wipe it dry immediately.
• Do not use unit around fire or expose it to fire in any way.