SENSIT Technologies VMD Operating instructions

851 Transport Drive • Valparaiso, IN 46383 (USA)
Phone: [phone] • www.GasLeakSensors.com
SET-UP & OPERATING INSRUCTION MANUAL
READ AND UNDERSTAND INSTRUCTIONS BEFORE USE.

CONTENTS
FOR YOUR SAFETY���������������������������������������������������������������������������������������������� 3
PARTS AND ACCESSORIES����������������������������������������������������������������������������������� 4
PRODUCT AND TECHNOLOGY DESCRIPTION�������������������������������������������������������� 5
SPECIFICATION ��������������������������������������������������������������������������������������������������� 6
SENSOR SPECIFICATIONS .....................................................................................................6
PRODUCT SPECIFICATIONS ...................................................................................................6
EXPLANATION OF PPM/M ���������������������������������������������������������������������������������� 7
INSTALLATION���������������������������������������������������������������������������������������������������� 8
INSTALL VMD INSTRUMENT ...................................................................................................8
INSTALL TABLET COMPUTER ...................................................................................................10
GETAC TABLET CONNECTIONS .............................................................................................11
USER INTERFACE������������������������������������������������������������������������������������������������� 12
DESCRIPTION OF INTERFACE BUTTONS..................................................................................13
USER SETUP TAB ...................................................................................................................15
OPERATION AND USE����������������������������������������������������������������������������������������� 16
CALIBRATION ����������������������������������������������������������������������������������������������������� 17
ADVANCED CALIBRATION ����������������������������������������������������������������������������������� 18
PLOTTING SURVEYS �������������������������������������������������������������������������������������������� 19
CONVERTING TO .KML AND EXPORTING...............................................................................19
PAIRING A PMD ������������������������������������������������������������������������������������������������� 20
IMPORTING CALIBRATION DATA INTO SCAL �������������������������������������������������������� 21
EXPORT DATA FROM TABLET TO REMOVABLE MEDIA................................................................21
IMPORT DATA INTO SCAL ......................................................................................................21
PAIRING BLUETOOTH CONNECTION�������������������������������������������������������������������� 22
GETACT T800 TABLET ............................................................................................................22
ADVANTECH TABLET .............................................................................................................24
NOTES ��������������������������������������������������������������������������������������������������������������� 25
WARRANTY�������������������������������������������������������������������������������������������������������� 28

3
FOR YOUR SAFETY
⚠ NOTICE: This safety symbol is used to indicate a potentially hazardous situation which, if not
avoided, may result in minor or moderate injury.
⚠ WARNING: Disassembly and maintenance is forbidden in explosive atmosphere.
⚠ WARNING: Follow the manual instructions and testing methods.
⚠ WARNING: Any disassembly or repair of the instrument must be done by a factory certified
technician.
⚠ WARNING: Clean lenses prior to each use with a lint free or microfiber cloth for best results.
⚠ WARNING: When not in use refer to transport position recommendation to prevent potential
damage.
⚠ WARNING: While the VMD is weather resistant, it is recommended to remove the instrument
and store it in the vehicle when necessary to avoid prolonged exposure to extreme
weather (i.e. heavy rain or snow).
⚠ DANGER: Use extreme caution when monitoring the tablet computer when driving. Rely on the
audible alarm instead of any visual indication while driving. Any adjustment should
be made only when the vehicle is safely stopped and away from traffic.

4
PARTS AND ACCESSORIES
STANDARD PARTS (INCLUDED)
360-00481 VMD Bluetooth antenna
360-00482 Tablet Bluetooth antenna
385-00159 Tablet Bluetooth antenna extension cable
(right angle)
330-00097 Tablet Bluetooth antenna clamp
360-00471 Tablet GPS antenna
385-00114 VMD power harness assembly
385-00160 Tablet vehicle power supply
360-00586 Tablet dock
882-00092-SN Calibration cell
(with mounting arm & thumbscrew)
882-00137 Extra power harness cover
360-00430 5A automotive fuse for power harness
STANDARD MOUNTING KIT (VMD)
870-00052 Mounting kit (includes parts below)
330-00078 Hitch pins
360-00426 Jam bolt
360-00427 L-bracket
360-00428 VMD bar bracket
360-00429 Hitch stabilizer
ACCESSORIES
870-00076 VMD shield
870-00105 VMD all-terrain shield
ALL-TERRAIN MOUNTING KIT (VMD)
870-00106 All-terrain mounting kit (includes parts below)
330-00078 Hitch pins
360-00426 Jam bolt
360-00429 Hitch stabilizer
360-00580 VMD all-terrain bar bracket
360-00581 VMD all-terrain L bracket
MOUNTING KIT (TABLET)
870-00074 Mounting kit (includes parts below)
360-00473 Base w/ 2” Ball & Clamps
360-00474 Arm
360-00475 Plate (VESA 75)

5
PRODUCT AND TECHNOLOGY DESCRIPTION
The SENSIT VMD®is a vehicle-mounted natural gas leak survey instrument. It uses IR Absorption
Spectroscopy technology for extremely accurate and consistent readings that are entirely methane specific.
The SENSIT VMD®uses an open-path system, which consists of 2 modules that are mounted on a bar.
One half emits a light source, which travels through the pace between the modules into the other half
which receives the signal. The amount of natural gas (methane) in the path affects how much of the light
source is absorbed, which is translated into a parts-per-million-per-meter (ppm/m) reading.
The entire assembly is mounted to the front of a vehicle on a large L-bracket, which is received by a 2”
hitch. The SENSIT VMD®is powered by a single cable coming from the battery of the vehicle, and can be
removed easily to allow for very fast and simple removal and storage of the instrument. The data it gathers
is sent via Bluetooth to a rugged tablet computer in the cab of the vehicle. The user is shown readings in
real time (at a rate of one reading every 200ms), on a very easy to read graphical interface.
The SENSIT VMD®, in addition to using Bluetooth communication, also utilizes a built-in GPS module
in the tablet. Combined with the software’s logging capabilities, the user can map a survey directly into
Google Earth, to see a detailed map of the survey with a breadcrumb trail of the path driven and readings
found.

6
SPECIFICATION
SENSOR SPECIFICATIONS
Sensitivity: 0.1 ppm/meter methane at a max speed of 25mph
Measurement Range: 1.0 to 1000 ppm/meter
Display Range: Automatic
Accuracy: ±10%
Alarms: Audible with adjustable set point
PRODUCT SPECIFICATIONS
System Voltage: 10-16 VDC
System Power Requirements: 84 watts max @ 12 VDC
VMD Size: 4 ft. to 8 ft. path length (5 ft. Standard)
Tablet Weight: 1.94lbs (0.88kg)
Tablet Size: 8.93” x 5.94” x 0.94” (227 x 151 x 24mm)
VMD Weather Resistance: IP54
Tablet Weather Resistance: IP65
Operating Temperature Range: -20˚F to 122˚F
Operating Humidity Range: 5 to 100% relative humidity
Installation Time: < 2 hours (typical)

7
EXPLANATION OF PPM/M
The SENSIT VMD®displays its readings in parts per million per meter. This is a representation of the
average gas concentration over 1 meter, or roughly 3.3 feet. Many types of IR and laser based technology
in the industry uses this standard. For implementations that are not fixed point, and have a variable path
length, the unit used is ppmm (parts per million meter). The difference being that the reading would be
a factor of the total distance of the path length, which can change as the size of the gas plume changes.
In the case of the VMD, the path length is fixed at slightly more than 1m, which is taken into account in
the software, and we therefore say the reading is “per meter”, meaning over the total length, since it never
changes.
However, this reading is still essentially an average. For example, consider the following images:
On the left, there is a natural gas plume with a concentration of 40ppm, spanning 0.5m. On the right,
there is a plume with a concentration of 80ppm, spanning 0.25m. Both of these scenarios will yield the
same reading of 20ppm/m. The plume on the right is double the concentration, but half the distance,
meaning the average concentration over the path length will remain the same.

8
INSTALLATION
INSTALL VMD INSTRUMENT
1. Install a 2” front-mount hitch on the front of the vehicle. If a bolt on hitch cannot be sourced, a local
welding shop should be able to mount one for you as pictured below.
2. Insert the short end of the L-bracket into the hitch with the long side facing up. There are several adjust-
ment holes for distance in and out from the bumper. Insert the pin and install and tighten the hitch
stabilizer. The hitch stabilizer tightens the L-bracket to the hitch, and therefore the frame of the vehicle.
This ensures that no extra vibrations are transferred to the VMD.

9
3. Ensure that the jam bolt is backed out from the bracket that is mounted to the VMD. Slide the VMD
and mounting bracket over the L-bracket, low-
er the VMD to the desired position, and in-
sert the pin. Tighten the jam bolt. It is recom-
mended to use an anti-seize compound on
the jam bolt.
4. Install the power harness assembly.
a. Route the power harness through the
grill and engine compartment to the
battery. The harness is 10ft long and
should have some slack left over.
b. The battery end of the power harness has two exposed wires, red for the positive terminal of the
battery and black for negative. Secure these wires to the battery. One method is to use crimp-on
ring terminals that can then be bolted to the battery terminals.
c. Plug in the power connector to the VMD.
d. It is recommended to use dielectric grease on all connections to prevent corrosion.

10
INSTALL TABLET COMPUTER
There are various methods for mounting the tablet computer. There is not a universal mounting system that
will fit all vehicles, and therefore Sensit does not provide a full tablet mounting solution. What is provided
is a ball-joint bracket and mounting arm. The ball-joint and mounting arm can be attached to the back of
the tablet with the provided hardware. The arm can then be secured to a pole that is mounted in the cab
of the vehicle (not provided). On an ATV or utility vehicle application, there will usually be a roll bar or
other similar structure that the arm can be attached to.
Alternatively, after market computer/tablet mounts are available from a variety of vendors. Most commonly,
these will use an arm or adjustable pole that will bolt to the front-passenger seat mounting points. This can
either be the full solution (which will mount to the tablet) or can sometimes be used in conjunction with the
provided ball-joint and arm.
If you need assistance with this, contact SENSIT Technologies.

11
GETAC TABLET CONNECTIONS
The provided tablet for the SENSIT VMD®is the Getac T800. Also provided is a dock for the tablet,
which has pass-through connections for the Bluetooth and GPS signals. The antennas for each is attached
to SMA connectors on the bottom of the dock. The Bluetooth antenna (8”) will most likely be pre-installed.
The GPS antenna has a magnetic puck with 10 feet of cable and will need to be installed by the user.
Refer to the picture below for a description of each connection. Also shown is the provided mounting arm.

12
USER INTERFACE
The user interface of the SENSIT VMD®is controlled by a tablet computer with a touch screen. The instrument
streams all data over Bluetooth to the tablet, where it is displayed in real time (200ms sample time).
The majority of the screen is reserved for survey data to be displayed. The bottom and left parts of the
screen have command buttons that can be used as needed. The top part of the screen has tabs for various
display modes and menus.
Refer to the image below and descriptions on the next page for how each of these buttons are used.

13
DESCRIPTION OF INTERFACE BUTTONS
Main Function Buttons (bottom of screen):
1. POWER ON / SHUT DOWN
Shuts off the VMD. Does not close the applica-
tion or shut off the tablet.
2. ZERO
Sets a new zero baseline for the current survey
(or next survey). Does not alter the calibration
or sensitivity of the instrument.
3. TEST
Performs a self-test function of the instrument.
A cell with a known concentration of gas in-
side the instrument is inserted into the detecting
path. The VMD detects this gas and shows the
operator a reading, as well as a test pass/fail
indication.
4. START/STOP_SURVEY
Starts or stops a survey. No readings will be dis-
played or recorded if a survey isn’t running. The
user will be prompted when starting a survey to
either save data to the previous log le or start
a new one (unless logging is disabled). Survey
must be stopped to calibrate the instrument.
5. PAUSE/RESUME
Pauses and resumes the survey instead of start-
ing and stopping. This will assume the user
wants to continue with the previous log le.
Also used to resume the survey if it gets inter-
rupted due to low light.
Function Button (left side of screen)
1. CLOSE
Closes the application but does not shut off
the VMD. This allows the user to bypass the
warmup period if the application is opened
again. When used, a timeout period of 10
minutes begins, after which the VMD will be
powered off. This is useful if the user needs to
access some other part of the operating sys-
tem, but wants to resume surveying afterwards.
2. CONVERT FILE TO KML
Menu for converting a datalog le to ‘.kml’ le
format instead of ‘.csv’. ‘.kml’ les are used for
viewing data with a mapping/GIS application,
such as Google Earth. GPS data is required in
order for a le to be converted.
3. VMD/PMD STREAMING
Status/indication icon for state of any stream-
ing options that are enabled.
4. GPS
Status/indication for GPS functionality. If no
GPS signal is available, the GPS text will be
red and the white box below it will be empty.
If a GPS signal is available, the GPS text will
be green and the coordinates will be displayed
below.
5. STAND BY
Puts the instrument in a low power state. User
must wait 120 seconds before use when it is
woken up.

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Display Modes/ Menu Tabs (top of screen):
1. NORMAL/WARMUP
Initial startup and warmup screen. Only shown
after rst power on and while the instrument is
warming up. Outputs basic sensor information.
The user does not need to interact with the in-
strument during this process.
2. SURVEY
Main operation mode for use of the instrument.
From this mode the user can start and stop
surveys, use the self-test function, calibrate the
instrument, etc. For more information, see the
sections on operation and calibration.
3. USER SETUP
Contains settings and conguration options
that are available to the user at any time. Alarm
settings, calibration logs, Bluetooth streaming,
etc. For more information, see the following
section.
4. SETTINGS
Password protected settings menu that contains
factory level adjustments.
5. DEBUG
Password protected menu that outputs debug
information. Only used for troubleshooting pur-
poses.
Other Buttons (upper right of screen)
1. CALIBRATE
Starts the calibration process. The user will be
prompted to place the calibration cell on the in-
strument. Calibration takes less than a minute.
See the calibration section for more information.
2. CLEAR CHART
Clears the current information on the screen.
This is only visual and does not restart the sur-
vey or remove any data from the log.
3. SHOW TABLE/SHOW GRAPH
Switches between displaying survey informa-
tion with a graph and with a table. The graph
(default) has a visual representation of the read-
ings in the form of a timeline, and is generally
preferred.

15
USER SETUP TAB
The user setup tab contains settings and configuration options that are available to the user at any time,
as well as calibration information. It is accessed by selecting the user setup tab from the top of the screen.
The survey must be stopped in order to access it.
From this menu, the user can:
• Change the graph settings for time displayed on the X axis (default 120 seconds) and PPM range
displayed on the Y axis (default 0).
° For the PPM setting, 0 means that there is no limit and the display will auto-range. Using another
value will fix the Y axis to that value and it will not adjust.
• Change the alarm set point (default 10).
• Change the Calibration Interval (default 90 days).
• Setup Bluetooth streaming and/or PMD Bluetooth settings
• View and export calibration data

16
OPERATION AND USE
⚠ WARNING: Always start any SENSIT®VMD in a gas free environment to ensure a proper zero.
1. Activate the computer by pressing the button located on the lower right hand side of the housing. The
system will boot up.
a. If the VMD application does not automatically begin, double click the icon on the desktop
screen.
2. Click power on to begin the warmup process, which will take approximately 8-12 minutes.
a. The graph and chart on the screen will show various diagnostic information during the warmup
process, such as the light level, sensor output, and internal temperature. This information is only
pertinent for troubleshooting purposes.
3. After the WARM UP and AUTOZERO complete, the display will show ready in the survey mode.
READY should be displayed in the upper left of the screen.
a. If the AUTOZERO failed, ZERO FAIL will be displayed. Please check that nothing is obstructing
the light path and that there is no dirt or other debris on the lenses. Try manually performing a
zero by pressing the ZERO (F2) BUTTON.
4. Travel to the area where the survey will begin.
5. If necessary, lower the VMD from the transport position (higher on the L-bracket) to the survey posi-
tion (lower on the L- bracket). The L-bracket allows for a broad range of height adjustment. Adjust as
needed and tighten the jam bolt. In general, the survey position should be as low as possible on the
L-bracket without any potential of collision.
6. Use the TEST (F3) BUTTON to do a self-test of the instrument.
a. A test can be performed at any time during a survey as well. It will be logged along with your
survey as test data (appears differently than survey data).
b. A TEST PASS or TEST FAIL message will be displayed in the upper right of the display after
the test has completed.
c. If the test fails, perform a calibration. A failed test pauses the survey. You can restart the survey
by using the RESTART (F5) BUTTON.
7. Press the start SURVEY (F4) BUTTON to begin the survey.
a. The user will be prompted to choose to add onto the previous log file or being a new log file.
This is useful if one survey or route has to be completed over multiple sessions.
b. Live readings will appear on the screen. By default this is shown as a graph, but can be displayed
as a table if desired.
c. If readings exceed the alarm point (10ppm/m default), an audible and visual alarm will be
triggered.
d. If at any time the light path is obstructed, the survey will stop and low light will be displayed
along with an audible tone and warning message. Check for obstructions in the light path or
any dirt or other debris on the lenses. Try to manually zero the instrument by pressing the ZERO
(F2) BUTTON.
8. Press the STOP (F4) OR PAUSE (F5) buttons as necessary to stop or pause the survey.

17
CALIBRATION
⚠ WARNING: Calibration must be performed in a gas-free environment. Calibration cycles over
90 days are not recommended. Using calibration kits other than recommended by
SENSIT Technologies may cause inaccurate readings. Repairs are required if the
instrument fails to calibrate. Consult the factory for details.
The SENSIT®VMD is calibrated with an external calibration cell assembly, which contains a known
concentration of gas trapped between two plates of glass. Unlike calibrating a conventional CGI, this
calibration process does not use a consumable. By default, the calibration cycle of the SENSIT®VMD
is 30 days, but can be increased or decreased to match your company policies. There is no harm in
performing a calibration process as often as desired (even daily).
1. Power on the instrument and wait for the warmup process to complete.
a. If the instrument is already powered on, calibration cannot be done while a survey is running.
The survey must be STOPPED and not PAUSED.
2. Hang the calibration cell on the bar of the VMD, so that the light will pass through it, up against the
housing of either module. Tighten the thumbscrew.
3. On the tablet, select the calibrate button. A dialog box will appear asking you to place the calibration
cell on the bar. Select OK. The calibration process will begin.
4. In the upper left of the screen, the current reading will be displayed as it is adjusted during calibration.
This should be very close to 100ppm/m. Once calibration is successful, READY will be displayed.
a. If calibration failed, CAL FAIL will be displayed. Attempt calibration again. If calibration
continues to fail, contact Sensit Technologies Service Department for assistance.
NOTE: In certain scenarios, if calibration fails, the instrument may need to have an advanced
calibration performed. In this case, the user will be prompted to do so with a dialog box after a
failed calibration.

18
ADVANCED CALIBRATION
⚠ WARNING: Calibration must be performed in a gas-free environment. Calibration cycles over
90 days are not recommended. Using calibration kits other than recommended by
SENSIT Technologies may cause inaccurate readings. Repairs are required if the
instrument fails to calibrate. Consult the factory for details.
Beginning with software revision 3.10(app)/3.02(firmware), advanced calibration is automatically be
performed instead of the normal calibration on a 90 day cycle. This process is described below.
1. After the calibration has started, the display will
change to the Advanced Calibration screen. This
process will take between 2-5 minutes to complete.
2. When the Advanced Calibration is done, the dis-
play will return to the survey screen.
3. A “PLEASE WAIT…” message will be displayed.
The user will be asked to remove the calibration
cell so that a factory zero can be automatically
performed. Press “OK” after the cell has been re-
moved.
4. The “PLEASE WAIT…” message will continue to
display for a few seconds. Afterwards, the cali-
bration will be complete.
a. If calibration is successful, READY will be
displayed.
b. If calibration failed, CAL FAIL will be
displayed. Attempt calibration again. If
calibration continues to fail, contact Sensit
Technologies Service Department for
assistance.

19
PLOTTING SURVEYS
The SENSIT®VMD saves a data log file for every survey conducted. These files will contain the date,
time, ppm/m reading, and GPS coordinates if available. With valid GPS coordinates, these files can be
converted to .kml format and viewed with mapping software. This gives a breadcrumb trail for the route
driven with the vehicle, including any readings found above the chosen alarm points and any self-tests
performed.
This section details how to convert these files, export them, and view them in Google Earth.
CONVERTING TO �KML AND EXPORTING
1. Power on the tablet computer. Allow it to fully boot and load the VMD application.
2. From the VMD application, select the CONVERT FILE TO KML from the upper left of the screen. The
VMD does not have to be powered on.
3. On the following screen, select SELECT FILE TO CONVERT. A le select window will appear.
4. Navigate to the location datalog le(s) that you want to convert. By default, the VMD will save log les
to the desktop.
5. Select one or more les and hit OPEN. You will be returned to the previous screen.
6. Make any adjustments necessary to the pin assignments. Anything below the value chosen for the yel-
low pin will not be shown on the map.
7. If you are planning to export right away to a ash drive, insert the drive now.
a. The USB port is on the right side of the tablet. Access it by pushing down the cover and lifting up.
8. Select CONVERT. A save window will appear.
a. If you get an error message, this means that one or more files you have chosen did not have valid
GPS coordinates. Any valid files in the selection can still be converted.
9. Navigate to the location that you would like to save the les to. If you are exporting to a ash drive,
select the drive from the list on the left.
10.Select save. A message will appear conrming that you have successfully created .kml le(s).
11.The .kml les can be opened directly into Google Earth to view the data.

20
PAIRING A PMD
The SENSIT®VMD and PMD have the ability to be used as a paired system. In this case, the PMD will
be used in conjunction with a vacuum system, with cones on the front of the vehicle being drawn from with
the aid of a powerful external pump. Readings from the PMD can be streamed real time using Bluetooth
to the VMD tablet, so that the user has information from both instruments at the same time.
Additionally, this information can be logged, along with the GPS coordinates from both instruments, which
can then be mapped with Google Earth. This is especially advantageous for use cases where the vehicle
will be stopped when a reading is found, and the leak will be pinpointed using the PMD. That way, the
path of the vehicle is shown as well as where the walking survey was conducted to find the leak.
When ordered as a system, the SENSIT®VMD and PMD will be shipped already paired from the factory.
If for some reason this needs to be done in the field, contact SENSIT Technologies for assistance.