LTL-XL RETROREFLEKTROMETER
Manual
On site quality control of road markings & road surfaces in accordance with CEN / ASTM
specifications
DELTA · Venlighedsvej 4 · 2970 Hørsholm · Denmark · Tel. +45 72 19 40 00 · roadsensors@delta.dk
DISCLAIMER
The information contained in this document is subject to
change without notice.
DELTA LIGHT & OPTICS MAKES NO WARRANTY OF
ANY KIND WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHAN-TABILITY AND FITNESS FOR A PARTICULAR PURPOSE. DELTA LIGHT & OPTICS SHALL NOT BE
LIABLE FOR ERRORS CONTAINED HEREIN OR FOR
INCIDENTAL OR CONSEQUENTIAL DAMAGES IN
CONNECTION WITH THE FURNISHING, PERFORMANCE
OR USE OF THIS MATERIAL.
LTL-XL IS BUILT ON GENERAL PUBLIC LICENSE COMPONENTS. THE SOURCS CODE IS AVAILABLE UPON
REQUEST.
Caution: Changes / modifications not approved by the responsible party could void the user’s authority to operate the
equipment.
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.
Update, August 15, 2012
Version 1.03 English
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TABLE OF CONTENTS
SECTION 1................................................................................................................................ 7
OPERATING INFORMATION ...................................................................................................... 7
LTL-XL introduction ................................................................................................................................ 7
LTL-XL retrometer features ..................................................................................................................... 8
Options...................................................................................................................................................... 8
Getting started ........................................................................................................................................... 9
Important guide lines for the correct use of the LTL-XL ....................................................................... 12
SECTION 2.............................................................................................................................. 13
GENERAL INFORMATION ........................................................................................................ 13
The measurement .................................................................................................................................... 13
Optical principle ..................................................................................................................................... 13
Notes on error sources ............................................................................................................................ 13
High temperature conditions. .................................................................................................................. 14
SECTION 3.............................................................................................................................. 15
THE USER INTERFACE .............................................................................................................. 15
Display and keyboard layout .................................................................................................................. 15
Measurement display .............................................................................................................................. 15
Upper icon row ....................................................................................................................................... 15
Lower icon row ....................................................................................................................................... 16
Push buttons ............................................................................................................................................ 16
The menu tree ......................................................................................................................................... 18
SETTING UP FOR MEASUREMENTS ...................................................................................... 19
Selecting a User ID ................................................................................................................................. 19
Selecting a road marking icon................................................................................................................. 20
Setting the date and time ......................................................................................................................... 21
Setting the dimmer and back light (Display) .......................................................................................... 22
Setting the sound level ............................................................................................................................ 23
Auto Sleep (Power) ................................................................................................................................. 23
Auto Off (Power) .................................................................................................................................... 23
Setting the language ................................................................................................................................ 23
Setting the temperature unit .................................................................................................................... 23
Setting the SMART key function ........................................................................................................... 23
Setting the AUX functions / GPS (optional) ........................................................................................... 24
Using GPS (optional) .............................................................................................................................. 24
Setup ....................................................................................................................................................... 25
MEASURE TYPE ........................................................................................................................... 27
RL & Qd ................................................................................................................................................. 27
Wet timer ................................................................................................................................................ 27
Timer Alarm ........................................................................................................................................... 27
Series id ............................................................................................................................................ 28
Working with series ID ........................................................................................................................... 28
Activate ................................................................................................................................................... 28
Selecting a series ID ............................................................................................................................... 29
Enter a new series ID .............................................................................................................................. 29
Removing a series ID .............................................................................................................................. 29
Setting the road marking icon ................................................................................................................. 30
The log .............................................................................................................................................. 31
Clearing data in the log ........................................................................................................................... 31
Viewing the log....................................................................................................................................... 32
View series data. ..................................................................................................................................... 33
Other settings .................................................................................................................................. 34
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Average function .................................................................................................................................... 34
Editing names ......................................................................................................................................... 35
Auto print ................................................................................................................................................ 35
Diagnostics ............................................................................................................................................. 35
The help system ...................................................................................................................................... 35
Errors and warnings ................................................................................................................................ 36
RSC program .......................................................................................................................................... 36
SECTION 4.............................................................................................................................. 37
MAINTENANCE ............................................................................................................................ 37
General care ............................................................................................................................................ 37
Protection window .................................................................................................................................. 37
Battery .................................................................................................................................................... 37
Fuses ....................................................................................................................................................... 39
Lamp ....................................................................................................................................................... 39
Calibration unit ....................................................................................................................................... 40
Calibration .............................................................................................................................................. 41
Printer (optional) ..................................................................................................................................... 43
Mounting the wheel unit (option) ........................................................................................................... 44
APPENDIX A ........................................................................................................................... 45
COMMUNICATION FACILITIES .............................................................................................. 45
APPENDIX B .......................................................................................................................... 46
SPECIFICATION ........................................................................................................................... 46
General characteristics ............................................................................................................................ 46
Environmental characteristics ................................................................................................................. 47
Mechanical characteristics ...................................................................................................................... 47
APPENDIX C .......................................................................................................................... 48
DELIVERY ..................................................................................................................................... 48
Visit our web-site “www.roadsensors.com”
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SECTION 1
OPERATING INFORMATION
LTL-XL introduction
The LTL-XL retroreflectometer is a portable field instrument intended for measuring the
retroreflection and reflection properties of road markings. LTL-XL measures the RL value
(coefficient of retroreflected luminance at night) and the Qd value (day light visibility). RL is
a measure of the lightness of the road marking as seen by drivers of motorized vehicles in car
headlight illumination. The road is illuminated at an angle of 1.24The illumination for Qd is
diffuse. The reflected light for both RL and Qd is measured at an angle of 2.29, which corresponds, to an observation distance of 30 meters. This is relevant for a motorist’s viewing situation under normal conditions. Further information on measuring principles and standards can
be found on “www.roadsensors.com/technical information”.
RL and Qd are important factors in the ON-SITE quality control of road markings.
Figure 1. The instrument
The operation of the retroreflectometer is very simple and requires minimal instruction.
The LTL-XL measures the retroreflectivity and calculates RL and Qd according to the international CEN and ASTM standards. Results are presented in plain text on a large graphic display. Error messages or warnings are shown in the display in case of any problems during use.
The memory of the instrument provides registration of measurements with corresponding
date, time and other relevant data. The following data is also registered (if enabled):
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Name of measuring series (road name)
Profile icon for road marking type
User name
GPS data (if installed)
Temperature & humidity
Instrument status
The measurement results can be printed by the build-in printer (optional). Communication
with a PC using the RSC (Road Sensor Control) software program (see pg. 36) allows for data
exchange with other PC programs.
A rechargeable NiMH (Nickel-Metal Hydride) battery powers the LTL-XL, giving hours of
measurement capacity. A mains powered battery charger is supplied as standard. Charging
time is approx. 1½ hour. The instrument can also be charged from a 12-18V source such as a
car battery using an adapter.
LTL-XL retroreflectometer features

Portable instrument
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Small dimensions / low weight
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Ergonomic operation height
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Fast measurement (completed in less than 1 sec. for RL or Qd and 3 sec. for RL +Qd)
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Measuring on dry and wet surfaces

Will measure flat, textured & profiled markings up to 5 mm
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Fully documented measurements with automatic data storage, user and series identification for labeling and grouping measurements
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Audible signals during use (if enabled)

RSC (Road Sensor Control) PC software for data exchange. Log data can be
exported to applications such as Microsoft Excel

Easy calibration procedure
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Traceable and accredited calibrated reflection standard
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User replaceable battery
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Fast charging (approx. 1½ hour)

Rechargeable from power adapter or a car battery using an adapter
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Average (2-25 readings)
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Multiple languages
Options
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Build-in GPS for precise logging of measuring location
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Wheel unit and extendable handle
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Build-in thermal printer
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Getting started
Buttons:
HELP
ON/OFF
MENU
SMART
HOME
CALIBRATE
BACK
PRINT
UP
LEFT
RIGHT
OK (center)
DOWN
Figure 2. Buttons
Height adjustment (optional)
Before using the LTL-XL, notice that the operating panel can be adjusted in height for ergonomic considerations. The height is adjusted by pressing the red knob on the front of the
instrument and at the same time lifting the handle on the operating panel. Release the knob
and continue lifting until the handle locks.
Switch on
Switch on the LTL-XL by pressing and holding the ON/OFF button
until the display
turns on. The instrument will be ready for measuring within 30-40 sec from cold. From
warn start the instrument will be ready within 1 sec.
Measuring
Calibrate the instrument if necessary. DELTA recommends calibrating the instrument every time the instrument is switched on and / or starts a new series of measurements. See Calibration, pg. 39
Place the instrument on the road marking.
Press the green OK-button
approx. 1 sec. / 3 sec.
to take a measurement. A measurement will be finished in
When the measurement is complete, the RL and/or Qd value will be displayed. Data is automatically transferred to the data log. If there is a problem with the measurement a warning icon or an error icon will pop up (see Errors and warnings, pg. 36) and an audible alarm will
sound (if enabled, see Sound settings, pg 21).
Measurements taken with a battery voltage that is too low are rejected or marked in the log
and an error icon appears.
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To print the last measurement data, press the PRINT button
User select (user initials)
.
If a user icon
is displayed in the upper icon row on the measuring display, press the UP
button ▲and if necessary ◄ or ► to mark the user icon. Press the OK button to enter the
user select menu. For further information see Selecting a user id, pg19
Series ID select (name)
If a user icon
is displayed in the upper icon row on the measuring display press the UP
button ▲to mark the road icon. Press the OK button to enter the series ID select menu. Select a name from the list using UP or DOWN and accept with OK or ENTER / EDIT a new
name.
Calibration
The instrument is supplied with a reference calibration unit. The reference calibration unit
is factory calibrated and traceable to PTB and NIST.
Calibration procedure
Before a calibration is carried out make sure that the calibration unit is clean.
To carry out a calibration go through the following steps:
 Before mounting the calibration unit check the RL and Qd values stamped on the calibration unit.
 Mount the calibration unit underneath the instrument. Make sure that the pins on the
interface plate fit into the holes on the calibration unit. Be very careful when you
place the instrument on the calibration plate not to damage the calibration unit and /
or the light diodes
 Press the CALIBRATION button
once. Select RL or Qd calibration to calibrate one
at a time.
 Check the value displayed, if necessary adjust the calibration value shown in the display so it matches the value stamped on the calibration unit. See the Calibration
section for details.
 Press the OK button to finish the calibration or repeat if erroneous.
 Repeat the calibration process for the other measure (RL, Qd)
The calibration procedure is now complete. Remove the calibration unit and store it properly.
Press OK to return to the measurement display. For further details see pg. 41.
Errors and warnings
An error or warning icon will appear in the upper row of the display if the LTL-XL detects
a problem. Press the UP button ▲ to get a description of the most serious error or warning.
Now press the OK button to display a total list of all errors or warnings related to the measurement and the instrument in general.
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Sound setting
Press the MENU button
and select SETTINGS / SOUND. Select KEY CLICK or SOUNDS to
set the individual sound levels for key click and system sounds. Use the UP ▲ or DOWN ▼
button to set the level. Accept the setting by pressing the OK button.
Miscellaneous
The HOME screen can be activated at any time by pressing the HOME button
.
Reset log:
Press the MENU button
and select LOG / CLEAR DATA.Now select from the menu: CLEAR LAST DATA, CLEAR ALL DATA or
CLEAR SERIES DATA.
Date and time:
Press the MENU button and select SETTINGS / DATE & TIME / SET
TIME/DATE. Use the UP ▲ and DOWN ▼ buttons to set the differrent time related settings.
Power save:
Press the MENU button and select SETTINGS / POWER / AUTO
SLEEP, AUTO OFF. Use ▲and ▼ to edit the values.
Data exchange / communication
The RSC software program, developed by DELTA for use on a PC, allows data to be exchanged between the LTL-XL and a PC. See RSC-program, pg. 36.
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Important guide lines for the correct use of the LTL-XL
Positioning of the instrument on the road marking
Select an area of the pavement marking that is level when taking readings. The measurement
field is marked with a yellow sticker on one side of the base cover. The measurement field is
approximately 50 mm wide and 185 mm long. Ensure that the pavement marking to be measured before taking measurements is free of debris. Make sure that the instrument is stable positioned.
Reason: The LTL-XL has three support pads, each with a small footprint, two smaller in the
front and one larger at the back. An uneven marking or a small piece of gravel trapped below
one of the pads will move the measurement field and affect the reading.
Taking the measurement
Press the green OK button to take a single or double reading as selected. Do not put pressure
on the handle when taking a measurement.
Reason: Pressure on the handle can affect the measurement geometry and thus influence the
reading.
Number of measurements.
For accurate readings, do not take just one reading of a road marking. Three readings will
give a more accurate result than one reading. Five readings will give an even more accurate
result than three readings, etc. Take the readings in adjacent areas of the marking. Let the instrument calculate the average of the readings (fixed or moving average options).
Reason: A road marking’s retroreflectivity varies from area to area. It is not unusual to see
variations of 5% - 20% when the instrument is moved even less than 10 mm / ½” in either
direction.
Protection of the display/display shield.
For the protection of the display and longevity of the instruments keep the display shield
closed when the instrument is not used. For further information please see section 2.
Remember:
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LTL-XL is an optical precision instrument, handle with care.
Keep the protection window and calibration unit clean and undamaged.
Store in a clean, dust free and dry environment.
Read:
Measurement practise for road markings. This leaflet can be located on:
http://www.madebydelta.com/imported/images/DELTA_Web/documents/LO/roadsens
ors/ltl-x-xl/Measurement-practise-for-road-markings.pdf
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SECTION 2
GENERAL INFORMATION
The measurement
The LTL-XL retroreflectometer measures the RL (coefficient of retroreflected luminance) parameter and Qd (the day light visibility). The RL parameter represents the brightness of road
markings seen by drivers of motor vehicles by headlight illumination. Qd measures the visibility of the road markings under day light conditions.
In the LTL-XL the illumination angle is 1.24 degrees for RL, the illumination for Qd is diffuse. Both observation angles are 2.29 degrees. According to both ASTM and CEN standards
these angle simulates a driver’s viewing distance of 30 meters. The instrument’s illumination
field is approximately 185 mm x 50 mm / 1.97 x 7.28 inch.
The LTL-XL is controlled by multiple microprocessors. It is operated with an extractable
keyboard located at the top of the retroreflectometer. It executes the measurement automatically by a push of the green button and presents the result on a display. The result is automatically transferred to the internal memory. The measurement, along with its corresponding time,
date, and other data can be printed using a printer (optional).
Optical principle
The optical system in the LTL-XL is covered by a patent. A LED lamp in the top of the tower
generates the light for the RL measurements. After a field stop the light is collimated by a lens
and deflected through a mirror toward the road. The diffuse Qd illumination is based on an
array of LED’s.
The reflected light from the road uses the same mirror and lens. Between the lens and the photo detector field aperture, stops define the observation area. The illumination field is inside in
the observation field. This is important to assure correct measurement on profiled markings.
V spectral correction is achieved by use of advanced optical filters.
Notes on error sources
Stray light can occasionally enter the instrument but will be insignificant under normal measurement conditions. Before each measurement, the LTL-XL automatically evaluates the leakage and compensates for it before the readout. In case of a significant leakage level, a warning
or error message is given and special precautions may be necessary.
Instrument leak, drift and offset errors are compensated by means of data obtained during the
calibration procedure. It is very important to keep the dust-protection window and the ceramic
on the calibration unit clean.
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The LTL-XL illumination angle is 1.24° relative to the road surface. Because of this small
angle accurate placement on the road is important. Avoid pebbles and abnormal irregularities.
The LTL-XL must be parallel and in contact with the marking surface.
The LTL-XL retroreflectometer is a rugged instrument, but it is an optical instrument and
must be handled as such.
The LTL-XL is factory calibrated. Nevertheless start measurements with a calibration. Study
the display for any warning or error icons. See also Section 4 - Maintenance
Note
Keep the dust-protection window and ceramics on the
calibration unit clean.
Keep the battery fully charged. A well charged battery is
more resistant to aging and damage.
High temperature conditions.
Display
If the display is exposed to intense direct sunlight during a longer period of time the display
could become overheated. It is recommended to close the protective display shield. The shield
also protects against damages and scratches. "Daylight readable" displays are vulnerable to
high temperatures. High temperature will decrease the display service life.
Battery
The battery is rated to operate between 0C / 32F and 45C / 113F.
Fig 3. LTL-XL, the inside
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SECTION 3
THE USER INTERFACE
Figure 4: The display
Display and keyboard layout
The user interface consists of a rectangular display surrounded by push buttons.
The display has two main modes: the measurement display (HOME screen) and the menu display. The instrument will start up with the measurement display shown. The display area is
divided into four areas: a large main display in the middle, an icon row at the top, a message
or caption field underneath and an icon row at the bottom.
Measurement display
Here the last measured RL and/or Qd values are presented with large digits together with other
information. On the graphic above, all possible information is shown in the display. If a function is deactivated, it will not be shown. The actual date and time is always shown.
Upper icon row
The upper row of icons is accessed by pressing the UP button ▲. One of the icons is then
highlighted and can be activated by pressing the OK button. The other icons in the row can be
accessed by using the LEFT ◄ or RIGHT ►buttons. The meanings of the icons are (from left
to right):

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
Series ID selection, can be switched off (see pg.26).
User ID selection, can be switched off (see pg. 19).
Error/warning alarm. Will be shown in case of an error/warning (see pg. 36).
GPS indication (see pg. 24).
Battery status (see pg. 39).
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Lower icon row
 From the lower icon row you can select a road marking icon that will be saved together
with the measurement in the log (see pg. 18) for future measurement identification. Access the icons by pressing the DOWN button ▼. Use the LEFT or RIGHT button to mark
the preferred icon. Pressing DOWN again shows more icon rows from a roll stack of five
rows. One row, marked with a "PR" for "Preset" can be preset by the user (see pg. 30)
and is saved separately for each measuring series. It will be the active icon row, ready
for selection, when a measuring series is selected.
 Activate the marked icon with the OK button or exit with the HOME
or UP ▲ button.
The selected icon is now shown in the left side of the HOME screen and the instrument
is again ready for measuring.
 Other functionality regarding the lower icon row:
Activating an already selected icon will cancel the activation and remove the icon from
the main display (and no icon will be saved by the next measurement).
Push buttons
OK
When the message row shows MEASURE, press the OK button to take a measurement. In most
other cases pressing the OK button will activate a highlighted selection.
ON/OFF
The button turns the instrument ON or OFF. Press the button to turn the instrument ON. It
will take 30-40 seconds from cold start, warm start within 1 sec. before the main menu is
shown and the instrument is ready to operate.
To turn the instrument OFF hold down the button more than 4 second until the display turns
black. If the ON/OFF button is held less than 4 seconds the instrument will go into standby
mode and enables warm start.
When the instrument is in standby mode, a short press on the button will turn on the display.
It is not possible to turn off the instrument during battery charging or when connected to a
USB port.
HOME
Bring you back to the measurement display.
BACK
Bring you backward one step in the menu and cancel new settings, which have not yet been
confirmed by the OK button. In most cases the LEFT button has the same function.
HELP
The button presents a context sensitive help text. The help presented will be on the subject
headline shown in the display. Another press on the button will open up a general help menu.
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Menu
The button selects the top level of the menu tree, the main menu. Use the UP and the DOWN
buttons to scroll through the menu items. Press OK to select the highlighted item. In most cases it opens up further submenu levels.
SMART
This button is user programmable to one out of several functions, e.g. to clear the last measurement, see pg. 23.
CALIBRATE
This button starts the calibration wizard, see pg. 41.
PRINT
Print out the last measurement or selected parts of the log to the internal printer.
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The menu tree
MAIN MENU:
SETTINGS
MEASURE TYPE
SERIES-ID
LOG
AVERAGE
DIAGNOSTICS
HELP
AUTOPRINT
SETTINGS:
USER
DATE & TIME
DISPLAY
SOUND
POWER
LANGUAGE
TEMPERATURE
SMART
AUX
SETUP
MEAS. TYPE:
RL
Qd
WET TIMER
TIMER ALARM
SERIES-ID:
ACTIVATE
SELECT NEW
EDIT
DELETE
PRESET MARK
LOG:
CLEAR DATA
VIEW LOG
AVERAGE:
AVERAGE
TYPE
NUMBER
RESET
DIAGNOSTICS:
INSTRUMENT
BATTERY
BOARDS
GPS
SYSTEM
USER:
SELECT
EDIT
NEW
DELETE
SEL. AT START
DATE & TIME:
TIME FORMAT
DATE FORMAT
SET TIME/DATE
TIME ZONE
SYNC TO GPS
DISPLAY:
BACKLIGHT
DIMMER
DIM LEVEL
BACKGROUND
SOUND:
KEY CLICK
SOUNDS
POWER:
AUTO SLEEP
AUTO OFF
AUX:
GPS
CLEAR LOG:
LAST DATA
ALL DATA
SERIES DATA
VIEW LOG:
LAST DATA
ALL DATA
SERIES DATA
HELP:
HELP ON KEYS
HELP ON MENU
HELP ON MEASUREMENT
HELP ON SERIES SELECT
ROAD MARKING SELECT
HELP ON USER SELECT
HELP ON EDITING
HELP ON AVERAGING
HELP ON GPS
HELP ON SETTINGS MENU
HELP ON SERIES-ID MENU
HELP ON LOG MENU
Figure: 5 – The menu tree
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SETTING UP FOR MEASUREMENTS
Selecting a User ID
The user ID (user profile) is used to identify the operator and is saved in the log together with
each measurement. If enabled, it can be seen at the lower left side of the measurement display.
Measurements can also be taken without a user ID. Unlimited user ID’s can be stored in the
instrument.
Certain instrument settings are stored individually for each user. Selecting a user will restore
these settings. All settings can be stored
The select procedure.
If a user select icon
is not seen in the upper icon row:
Press the MENU button and select SETTINGS / USER / SELECT to display the USER menu.
1. If a user select icon is seen in the upper icon row:
Press the UP button. Then, if necessary use the LEFT or RIGHT button to highlight
the user icon. Press the OK button. The USER menu is shown:
Now use the UP or DOWN button to highlight a user name. Press the OK button to accept the
name.
Changes made to the above mentioned individual instrument settings are automatically stored
in the selected user ID.
Selecting OFF will deactivate the user function and set all individual instrument settings to
default.
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Edit user
User names can be edited from the menu SETTINGS / USER / EDIT (see editing pg. 35).
New user
A new user can be entered from the menu SETTINGS / USER / NEW (see editing pg. 35).
Clear user
Deleting the User ID will remove the user and settings from the memory.
Select at start
Enabling SEL. AT START will force the user to select a user ID each time the LTL-XL is
turned on.
Press the MENU button and select SEL. AT START. Press OK to toggle between YES and
NO
Selecting a road marking icon
The purpose of a road marking icon.
The road marking icons are used as labels for the individual measurement corresponding to
the measured road marking and will be saved in the log together with the measuring result.
The icon will then be presented together with the corresponding measurement when viewing
the log or by using the RSC program (see pg. 36).
There are 29 fixed icons to select from. Six of the icons can be programmed as individual presets for each series (see pg. 30) and will be ready for selection when a series is selected.
The procedure.
From the HOME screen press the DOWN button. Then use the LEFT or RIGHT button to highlight the wanted icon. Pressing DOWN steps through and displays the five icon rows. Pressing
UP will return to the HOME screen without selecting a new icon.
Pressing the OK button will activate the selected icon. The selected icon is now shown in the
left side of the measuring field and the instrument is again ready for measuring.
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Deactivating the profile icon.
Activating an already selected marking icon will cancel the activation and remove the icon
from the main display.
Setting the date and time
Date and time is always shown in the display. Every measurement taken is marked with the
date and time, so it is essential that the settings are correct.
Press the MENU button and select SETTINGS / DATE & TIME. Press OK and the time format sub
menu is shown.
Setting the time format
Press OK when TIME FORMAT is highlighted and scroll between 12 and 24 hr format.
Setting the date format
Press OK when DATE FORMAT is highlighted.
Highlight the preferred date format using UP or DOWN. Press OK to accept.
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Setting the time and date
Press OK when SET TIME/DATE is highlighted.
Press OK to activate each line and use UP or DOWN to set the figure. Press OK to accept the
setting. Note: the time in this menu is not live, but it will synchronize the time shown in the
HOME screen.
Setting the Time zone
Press OK when TIMEZONE is highlighted. Press OK to open up the list of countries / national
time zones. Scroll to the country / national time zone you live in and press OK to select.
Synchronize to GPS
When SYNC. TO GPS is highlighted press OK to scroll between ON and OFF. By activating
this function be aware that if the time zone is changed, then recorded date and hour in the
memory will be changed to the new time zone. This function will also secure automatic
change of day light saving time.
Setting the dimmer and back light (Display)
The backlight and dimmer can be adjusted. Press the MENU button and select SETTINGS /
DISPLAY.
The levels can be adjusted on a scale from 1 (lowest intensity) to 10. Press OK to activate the
function and use UP and DOWN to change the values. Press LEFT or BACK to store.
It is also possible to adjust the time before the light switch to dimmer mode from 5 to 120
seconds or set to OFF. The back-ground colour of the display can be switched off.
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WARNING: Using high backlight will drain the battery faster!
Setting the sound level
Press the MENU button and select SETTINGS / SOUND. Select KEY CLICK or SOUNDS to set
the individual sound levels for key click and warning and error sounds. Use the UP or
DOWN button to set the level at OFF or a scale from 1 to 10. Accept the setting by pressing
OK, LEFT or BACK buttons.
Auto Sleep (Power)
To save power the instrument can be setup to automatically change to Auto Sleep mode. The
Auto Sleep time can be set from 1 to 30 min. in intervals of 1 min. or it can be deactivated
(OFF). Startup will be instantaneous pushing the ON / OFF button.
Press the MENU button and select SETTINGS / POWER / AUTO SLEEP. Use UP and DOWN to
edit the auto turn sleep time. Press OK, LEFT or BACK to accept.
Auto Off (Power)
To save power, the instrument can be programmed to automatically shut off if not used.
When communicating with RSC program or when the charger is connected the instrument
will not power down automatically. The startup time will be approx. 20-25 seconds.
Press the MENU button and select SETTINGS / POWER / AUTO OFF. Use UP and DOWN to edit
the auto turn off time. The off time can be set from 1 to 8 hours in intervals of 1 hour or it can
be deactivated (OFF). Press OK, LEFT or BACK to accept.
Setting the language
Press the MENU button and select SETTINGS / LANGUAGE. Use the UP or DOWN button to
select a language. Accept by pressing the OK button or leave unchanged by pressing BACK.
Setting the temperature unit
Press the MENU button and select SETTINGS / TEMPERATURE. Use the OK button to select between Celsius and Fahrenheit. Accept by pressing the BACK button.
Setting the SMART key function
This button is user programmable to one of several functions, e.g. to clear the last measurement. Press the MENU button and select SETTINGS / SMART.
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Use the UP or DOWN button to select the SMART KEY function. Accept by pressing the
OK button.
The selected function is now accessed every time
is pressed
Setting the AUX functions / GPS (optional)
The AUX function is used to control auxiliary built-in equipment like putting the GPS receiver on and off.
Using GPS (optional)
The GPS receiver is mounted inside the instrument, drawing its power from the internal battery. The GPS system is used to supply position data (latitude and longitude) to the log together with the measurement data.
If activated a GPS icon is shown in the upper icon row (see picture pg. 15). The icon will display
the quality (reliability) of the GPS signal.
Below is an explanation of the GPS icon states.
GOOD:
The GPS HDOP (Horizontal Dilution Of Precision) value is below 5.
FAIR:
The GPS HDOP value is larger than 5, but the GPS can FIX.
NO:
The GPS cannot FIX (weak or no signal).
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The GPS position data, HDOP value, and the number of satellites used in the position calculation are saved in the log together with the RL and Qd data.
Activating the GPS
Press the MENU button and select SETTINGS / AUX, highlight the GPS line and press the OK
button to toggle the GPS ON or OFF. Press the BACK button or the HOME button to return to
the HOME screen.
The GPS data can be viewed from the HOME screen by pressing the UP button and then highlighting the GPS icon by using LEFT or RIGHT buttons. Press the OK button to display the
GPS data. When the GPS data changes the display is updated.
If the GPS does not fix and a measurement is taken a warning menu appears. You will be presented with the following option:
 No GPS fix, Measure anyway, NO / YES
More about the GPS
The GPS unit will typically acquire satellite signals and process a position fix in 1-15 seconds. If the GPS receiver has been turned off for a long period of time (>1 week), the time to
first fix will take longer.
The GPS engine used has a navigation performance of 2.5 m CEP1)
The precision of the GPS receiver in the LTL-XL is determined by many factors. A few are
listed below:
 Signal obstruction. The GPS receiver requires a clear view of the sky. Trees, buildings and other environmental objects may affect the satellite signals.
 Satellite constellation and geometry.
 Multi path (reflection of signal from buildings etc.).
The HDOP (Horizontal Dilution of Precision) is a number that indicates the quality and precision of the received GPS data (low values are better than high).
When the GPS is used, the operating time for the LTL-XL will be decreased and you may
have to charge the battery more often.
1)
CEP (Circular Error Probable):
A statistical measure of the horizontal precision. The CEP value is defined as a circle's radius, when
centered at the true position, encloses 50% of the data points in a horizontal scatter plot. Thus, half the
data points are within a 2-D CEP circle and half are outside the circle.
Setup
Setup is used to separate between basic and advanced users. The basic settings reduce the
number of menus available to the user. For example, in basic menu operation, users cannot
clear the log.
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The following menu points can be selected in basic mode:
Settings:
User, Date & Time, Display, Sound and Temperature, Setup
Measurement type: RL, Qd, Wet timer, Timer alarm
Log:
View log
Diagnosis:
Instrument, Battery, Boards, GPS, System
Help:
All menus available
Auto Print
ADVANCED setting will provide access to all menu functions.
To change the setup, press MENU and select SETTINGS / SETUP. Pressing OK will toggle between ADVANCED and BASIC. To return from setup press BACK or HOME.
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MEASURE TYPE
RL & Qd
Enables or disables RL and/or Qd measurement
Wet timer
The wet timer function works for RL measurements only. The timer can be adjusted between
15 and 60 seconds. The wet timer carries out the measurement after the set period of time.
Timer Alarm
Can be set to carry out automatic measurement or sound an alarm when time to measure.
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SERIES ID
Working with series ID
The purpose of a series ID
The series ID is a label, for example the name of a road. Although measurements can be performed without selecting a series ID, it is convenient to group (name) the measurements for
each geographical spot, road or part of a road for easier recognition. The series ID for such a
group of measurements will be saved in the log together with the measuring results. The ID
must be selected prior to the measurement.
The individual measurements in a group can further be labeled by selecting a road marking
icon (see pg. 27) corresponding to the actual road. Measurements taken with the same series ID
are automatically marked.
The instrument can store unlimited series ID’s.
Activate
To use the series ID it must be activated. Press the MENU button and select: SERIES ID /
ACTIVATE SERIES. By pressing OK you can toggle between ON and OFF, to activate or deactivate the series ID function. Press BACK or press the HOME button to return to the HOME
screen. When the series ID is off no ID is shown in the display.
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Selecting a series ID
From the HOME screen press UP. If necessary, use the LEFT or RIGHT button to highlight the
road icon
. Press the OK button. The SERIES ID menu is shown. Choose SELECT to access the available series ID.
Press the OK button to accept the name.
Enter a new series ID
Do the same as above but select NEW from MAIN MENU / SERIES ID. Proceed by spelling the
series name (see Editing pg. 33). Press END in the spelling section to save.
Edit a series ID
Do the same as above but select EDIT from MAIN MENU / SERIES ID. Proceed by editing the
series name (see Editing pg. 33). Press END in the spelling section to save.
Removing a series ID
This will remove the series ID from the selection list. Press the MENU button and select
SERIES-ID / DELETE:
Use UP or DOWN to select the series that should be deleted. Accept by pressing the OK button. A confirmation menu is shown: “Are you sure? Yes. No”
Note! All measurements in the selected series will be erased from the log!
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Setting the road marking icon
Six of the 30 icons symbolizing road markings can be programmed as individual presets for
each series ID and will be ready for selection when a series ID is selected. Press the MENU
button and select SERIES-ID / PRESET ROAD MARKINGS to enter the SELECT MARKING menu:
The bottom line shows the present six preset icons.
Use the LEFT, RIGHT, UP and DOWN buttons to choose a new icon for the first position, accept by pressing the OK button and the cursor (frame) will move to the second icon. Repeat
for all six icons and the programming is done. You can amend at any point by pressing the
BACK button and start over again. Press the BACK or HOME button to save.
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THE LOG
Each time a measurement is taken data is stored to the log. The following data, among others,
are saved, if enabled:
 Measurement result incl. average
 Date and time.
 Name of measuring series (road name) and sequence number.
 Road marking icon
 User name
 GPS data (if installed).
 Instrument status
 Temperature & humidity
The instrument can store >200.000 measurements in the log.
Clearing data in the log
Press the MENU button and select LOG / CLEAR DATA:
This menu gives the option to clear data; the last measurement, all measurements or one of
the measuring series stored in the log. By pressing the OK button you will be asked to confirm
the erasure of the data. By pressing LEFT data will be cleared, by pressing OK they will not
be cleared.
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If you selected SERIES, you may select the series you wish to delete from the log from the list
shown. Only the log entries will be erased. The series will still be available in the series select
list.
Viewing the log
Press the MENU button and select LOG / VIEW LOG:
This menu gives the possibility to view or print data from either the last measurement, from
all measurements or from one of the measure series stored in the log.
The figure below shows the data logged from a measurement
In the first line, the menu shows the RL and Qd value, thereafter in the following lines other
key measurement data. To view a list of the individual errors/warnings in the status, print out
the measurement (see below).
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Each time a measurement is taken, a status information is generated. If any error occurs the
information can be interpreted by the warning/error icon in the top line of the display. The
information is available until a new measurement is taken or the problem is resolved. The status information is also stored in the log.
GPS indicates that valid GPS data was stored with the measurement.
Press the PRINT button to print the log from the highlighted measurement.
To return to the log menu, press BACK
View series data.
In the log menu, select SERIES DATA to view the list of series.
The menu shows a series ID in each line. By pressing DOWN or UP, the individual series are
highlighted. Highlight a series and press the OK button to view the individual measurements.
Highlight a measurement in the individual display and press the PRINT button to print the
log.
To return press the BACK button.
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OTHER SETTINGS
Average function
An average function can be activated showing the average of the measured RL & Qd values
calculated over a selectable number of measurements (N = 2 to 25). The average mode can be
fixed or moving. In moving mode the average is always calculated from the last N measurements where N is the selected number of measurements. In fixed mode the averaging will
start over again when N measurements have been taken. The average data is shown in the
HOME screen at the lower right corner (see picture pg. 15).
Press the MENU button and select AVERAGE:
AVERAGE:
Use the UP or DOWN button to highlight the first line. Press the OK button to toggle between AVERAGE ON and AVERAGE OFF.
TYPE:
Highlight the second line and press the OK button to toggle between type: MOVING
and type: FIXED.
NUMBER:
Highlight the third line and press the OK button to focus on the NUMBER digits. Then
use the UP or DOWN button to change the value between 2 and 25. Finally press the OK
button to confirm the new value. The default setting is 4.
RESET:
Highlight the fourth line and press the OK button to reset the calculated average value
and reset the number of measurements included in the average to zero.
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Editing names
From certain points you arrive to the EDIT menu e.g. is you want to define a USER. You will
arrive to the following screen:
With UP, DOWN, LEFT and RIGHT you can navigate around the letters, numbers, symbols
and space. The “arrow” will take you one step back. Press enter to select. When you have finished, press END to return to the menu, where you started.
Auto print
Press the MENU button and highlight AUTOPRINT. Press the OK button to toggle between ON
and OFF. If AUTOPRINT is activated a print is automatically made every time a measurement
is taken. Press BACK to return to MENU.
Diagnostics
Press the MENU button. Highlight the line DIAGNOSTICS. Press the OK button, and the menu
showing the following:
Each line gives information aimed at extended service and factory use. The information presented on the screen will be printed if you press the PRINT button.
The help system
Press the HELP button to show a context dependent help page. Pressing HELP once more will
present a general help menu in which you can highlight a subject by using the UP or DOWN
button and the press the OK button to show the help text. The HELP section is also accessible
on the main menu.
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Errors and warnings
When a measurement is taken, a warning text is generated if a problem arises and saved in the
log together with the measurement. If a problem occurs, a warning icon
or an error icon
is show above the HOME screen and an audible alarm is sounded (if enabled) and error
is stored in the log.
To view the nature of the problem, press the UP button and the warning/error icon will be
highlighted. The most severe problem will be stated in the message line underneath.
Then press the OK button to view a total list of problems starting with the most severe.
Press the BACK button to return to the HOME screen. If the problem did not hinder the completion of the measurement, the erroneous value(s) will be saved in the log, which can identify the problems when the log is evaluated using the RSC program. If an error is registered the
measurement will not be recorded.
RSC software program
Main features of the RSC (Road Sensor Control) software program delivered together with
the LTL-XL:
 Transfer of log data to a PC
 Export of log data to other programs e.g. spread sheets
 Printing reports of the log data
For more details see the separate user’s manual for the RSC program, found on the installation CD.
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SECTION 4
MAINTENANCE
General care
The retroreflectometer is constructed for outdoor use in ordinary good weather conditions. It
will stand moist weather with wet roads, but caution must be taken against heavy rain and
dirt. The LTL-XL retroreflectometer is an optical instrument and shall be handled as such.
Avoid shock and vibration if possible.
Protection window
The protection window is accessible from underneath of the instrument. The protection window is coated with a high-efficiency anti-reflection coating. Take care not to damage this
coating when cleaning. Compressed air or a fine brush can be used for removing loose particles/dust. If this is not sufficient the window should by cleaned using a soft paper tissue or
cloth and some window cleaning liquid.
MAKE SURE THE PROTECTION WINDOW IS CLEAN AND UNDAMAGED AT ANY
TIME TO ENSURE CORRECT MEASUREMENT RESULTS
Battery
The LTL-XL retroreflectometer is powered by a 12V/2.1 Ah NiMH (Nickel-Metal Hydride)
battery. Under normal use, this battery requires no maintenance. However it is recommended
to keep the battery fully charged. A fully charged battery is more capable of withstanding degeneration.
A battery charger power supply is provided as a standard accessory for charging the battery
from mains. The output cable of the charger is equipped with a connector matching the connector in the instrument. Connect the charger to an outlet and the instrument. If the instrument
was turned off it will automatically power on when the charger is being connected. The battery icon in the upper right corner will also indicate the charging state.
No harm will result from leaving the charger connected after the charging process. However,
the instrument must be disconnected from the charger when disconnecting the battery from
the wall outlet. In addition, the battery can be charged using any DC supply from 12-18 V.
such as a car battery by using an inverter or the 12V charger supplied by DELTA (optional).
When storing the instrument for a long period of time fully charge the battery.
THE BATTERY SUPPLIED WITH LTL-XL IS SPECIALLY DESIGNED FOR THE
INSTRUMENT TO ENSURE SAFE USE. IF A NON DELTA SUPPLIED OR APPROVED
BATTERY IS USED WITH LTL-XL DELTA CAN TAKE NO RESPONSIBILITY FOR
ANY DAMAGED CAUSED DUE TO THE PERFORMANCE OF THIS BATTERY.
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Replacing the battery
A worn out battery will not hold a charge very long. When the battery is worn out it must be
replaced. The user can do this.
The battery is located in a compartment at the low end of the rear of the tower. To replace the
battery, remove the screws from the back cover and remove the cover.
Loosen the big screw at the battery cover. You can now remove the cover
Lift the battery out of the compartment. Press the snap-on clip on the connector and carefully
withdraw it from the printed circuit board
The battery can now be removed and replaced. Refit in reverse order. Please check your local
regulation for disposal of the battery
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Battery status
The capacity of the battery can be seen from the icon in the upper icon row.
Indicates that the battery is fully charged
Shows that the fast charging is finished
Shows that fast charging takes place
Indicates that the capacity of the battery is half empty
The battery is almost empty and need recharging
Fuses
Two fuses are located in the battery compartment. The charging fuse protects the battery
against short circuit and other errors in the charging connector, charger or charging system.
The battery fuse protects the battery and electronics against short circuit and other errors in
the electronic system.
Always replace a blown fuse with one of equal rating See Electrical Characteristics pg. 44. To
change the fuses you need access to the battery compartment. See replacing battery pg. 35. Carefully unscrew the plastic cap fuse holder by using e.g. a coin. Pull out the fuse from the cap and
insert the new one and reassemble
Charger fuse
Main fuse
Lamp
The lamps are maintenance free LED lamps. Only trained personnel should replace the lamps
if damaged.
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Calibration unit
Reference
The road marking is simulated by a piece of white ceramic (the reference) mounted on an
aluminum profile. Ceramics have very stable optical properties because of the smooth surface.
Figure: 6 - Calibration normal
To make sure that calibration of the retroreflectometer is correct it is important that the ceramics and light trap on the calibration unit is clean and undamaged. Always keep the calibration
unit well protected.
If the ceramic is stained, scratched or broken, the calibration unit has to be repaired and recalibrated. In case of dust on the ceramics surface of the reference, the use of compressed air is
recommended for removal. The use of a soft damp cloth is recommended if compressed air
fails to remove the dirt. If necessary, use a mild household detergent.
Service
To ensure reliable measurements, it is recommended that the calibration unit be periodically
recalibrated to a traceable standard. DELTA offers calibration traceable to PTB (PhysikalsichTechnische Bundesanstalt, Germany) and NIST (National Institute of Standards and Technology, USA).
For information in service please contact your distributor or DELTA directly. At DELTA you
can forward your request via our web-site www.roadsensors.com or send a mail directly to:
roadsensors@delta.dk.
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Calibration
The LTL-XL is factory calibrated and very stable but a calibration should always be carried
out before starting a new series of measurements. The instrument is supplied with a calibration unit to carry out a fast and easy calibration.
Back
Front
Figure 7: Placing the calibration unit
Calibration procedure
 Before mounting the calibration unit check the RL and Qd values stamped on the calibration unit. Place the instrument upon the calibration unit and pull back until the
pins at the back and front of the LTL-XL are in place, see figure 7. Please be very
careful when you place the instrument on the calibration plate not to damage the
calibration unit and / or the light diodes
Press the CALIBRATION button
once. Select CALIBRATE RL or CALIBRATE QD.
Continue the calibration process applying the following steps
 Check the value displayed and, if necessary, adjust the calibration value shown in the
display so it matches the value stamped on the calibration unit.
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 Press the OK button to finish the calibration or repeat if erroneous.
 Repeat the calibration process for the other measure ( RL, Qd)
The calibration procedure is now complete. To check the calibration, make a normal measurement on the calibration unit. The recorded values should be with +/- 2-3 units of the values
stamped on the calibration unit. Remove the calibration unit and store it properly. Press OK to
return to the measurement display. For further details see pg. 41.
The instrument automatically compensates for zero signals, leakage and other known errors,
and calculates a calibration factor.
Always store the calibration unit in a dry, dust free and clean environment.
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Printer (optional)
The printer is located at the back of the tower. The printer is a high-speed high quality mini
thermal printer. It has only a few moving parts and does not require any special or periodic
maintenance.
The printer uses a thermal paper roll, width: 57.5±0.5 mm (2.26 in), diameter: max. 31 mm
(1.22 in)
Replacing paper
Replacing the paper is simple. First, pull the little lever out with your finger and the cover will
open into the paper roll compartment.
Insert the new paper roll and let a short paper tail hanging out at the top. Close the cover with
a firm push and with some of the paper sticking out.
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Mounting the wheel unit (option)
A wheel unit can be mounted in the rear of the instrument for easy transportation during
heavy use.
The wheels are mounted easily to the rear
by fastening the two nuts mounted on the
wheel block.
Nuts for fasten the wheels
Figure: 8 – Mounting the wheels
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APPENDIX A
COMMUNICATION FACILITIES
The LTL-XL is equipped with a USB Master Port and a USB Device Port.
The USB Master Port can be used to connect to a USB memory stick, e.g. for software updates.
The USB Device Port is used to connect the instrument to a PC.
The ethernet connector is for test / service purpose.
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APPENDIX B
SPECIFICATION
General characteristics
Illumination angle ............................................................................................................ 1.24º
Observation angle ............................................................................................................ 2.29º
Equivalent observer distance ........................................................................................... 30 m
Observation angular spread .......................................................................................... ±0.17º
Type 30m CEN
Illumination angular spread horizontal ........................................................................ 0.33º
Illumination angular spread vertical ............................................................................ 0.17º
Field of measurement:
Width ............................................................................................................ 50 mm (2.0 in)
Length (typ.)............................................................................................... 185 mm (7.3 in)
RL range (mcd·m-2·lx-1)................................................................................................ 0-2000
Qd range (mcd·m-2·lx-1) ................................................................................................ .0-318
Radio: ........................................................................................... EN 300440-1 V1.6.1:2010
EMC: ............................................... EN 301489-1 V1.8.1:2008, EN 301489-3 V1.4.1:2002
Safety : ...................................................... EN/IEC 60950-1 :2006, EN/IEC 60950-22 :2006
FCC: .................................................................................. 47 CFR, FCC Part 15B, Class A
Power supply:
Battery .................................................................................Built in 12 volt / 2.1 Ah NiMH
External charger power supply .................... Friwo FW7530/15 (100-240 VAC / 15VDC )
Charging time .................................................................................. Approx. 1 hour 30 min
Charger fuse (5*20 mm) .......................................................................................... T3.15A
Power supply fuse (5*20 mm) ................................................................................. T3.15A
Data memory .................................................................................... >200.000 measurements
Data transfer ................................................................................................................USB 2.0
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Environmental characteristics
Temperature:
Operating ........................................................................... 0ºC to + 45ºC (32ºF to +113º F)
Storage*) .......................................................................... -15ºC to + 55ºC (5º F to +131º F)
Humidity ......................................................................................... 85% and non-condensing
*)
Battery must be fully charged
Mechanical characteristics
Max. length ................................................................................................. 573 mm / 22.56 in
Max. width .................................................................................................... 222 mm / 8.74 in
Max. height ................................................................................................. 538 mm / 21.18 in
Weight of base unit ............................................................................................7 kg / 15.5 lbs
Construction:
Structural parts .................................................................................................... Aluminum
Housing .................................................................................................................. Polymer
Keyboard ...................................................................................................... Silicone rubber
Circuit boards .................................................................................................... Epoxy glass
Printer:
Thermal paper ......................................width/dia. 57.5 ±0.5 mm / 31mm (2.26 in / 1.22in)
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APPENDIX C
DELIVERY
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