LTL2000 RETROMETER Manual On site quality control of road markings & road surfaces in accordance with CEN specifications DELTA - Hjortekærsvej 99 - DK -Kgs.
DISCLAIMER The information contained in this document is subject to change without notice. DELTA LIGHT & O PTICS 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. Rev.
INDEX SECTION 1 ............................................................................................................................... 1 OPERATING INFORMATION...................................................................................................1 LTL2000 Introduction......................................................................................................................................................1 LTL2000 Retrometer features:............................................
Special Status Printouts. ......................................................................................................... 39 Initial Status....................................................................................................................................................................40 Status after first Zero.....................................................................................................................................................
SECTION 1 OPERATING INFORMATION LTL2000 Introduction The LTL2000 Retrometer is a portable field instrument, intended for measuring the retro reflection properties of road markings in car headlight illumination, the value Rl (coefficient of retro reflected luminance) is used. Rl is a measure of the lightness of the road marking as seen by drivers of motorised vehicles in car headlight illumination. The road is illuminated at an angle of 1.24° and the reflected light is measured at an angle of 2.
The LTL2000 is powered by a rechargeable lead acid battery, giving several hours of measurement capacity. A mains powered battery charger is supplied as standard.
Getting started: Turn the LTL2000 on by pressing Hold pressed until LCD shows: Retrometer è Ready LTL2000 rev. n Calibrate instrument if necessary, see Calibration Remove the base frame and place the instrument over the road marking. Press button. Measurement will start instantly, duration app. 3 sec. When finished the measured Rl value, the date/time and status prompt is displayed.
Edit the value until it corresponds with the Normal value and then press . The Calibration is now completed and the values stored. Control Calibration. Use in case of doubt during on site measurement. Follow the traceable calibration procedure using the red control calibration unit. Use the Rl value from the control calibration unit label. Transfer of calibration value.
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Communication Use a simple terminal or PC with communication software to control the LTL2000. (Windows Hyper Terminal will do fine.) Serial communication setup (RS232 interface): 9600 baud, No parity, 8 bit, 1 stop Xon/Xoff handshake Selected commands ? LR LT RL RT SD (Help): LTL2000 will return command set (Log dump): Date, time, Rl, status, mode. (Test log dump): Date, time, Rl, lamp on/off, idle, load, status, mode. (Rl measurement): Rl, date, time, status code, system info.
SECTION 2 GENERAL INFORMATION Rl Measurement LTL2000 Retrometer measures the Rl (coefficient of retro reflected luminance) parameter. The Rl parameter represents the brightness of the road markings seen by drivers of motor vehicles by headlight illumination. In the LTL2000 the illumination angle is 1.24° and the observation angle is 2.29° simulating a drivers viewing distance of 30 metres at an eye hight of 1.2 metres. The observation area is app. 45 mm. x 200 mm.
The LTL2000 is controlled by a microprocessor. The microprocessor executes the measurement automatically by the push of a button and presents the result on a display. The result is automatically transferred to an internal non-volatile memory. The result and corresponding time and date can be printed by the built-in printer. The LTL2000 is operated with a small keyboard located at the top of the Retrometer. Further, Retrometer control is possible over a serial communication link (RS232).
The LTL2000 Retrometer is a rugged instrument, but it is an optical instrument and must be handled as such. The LTL2000 is factory calibrated. Nevertheless start important measurements with a calibration before removal of the base frame. Study the Retrometer status and error messages if any. See also Section 4 - Maintenance Note Keep light trap, dust-protection window and ceramics on calibration unit clean. Keep battery fully charged.
SECTION 3 KEYBOARD, DISPLAY AND FUNCTIONS Keyboard Layout RL CALIB. ENTER TEST ZERO CANCEL MENU OFF ê ON PRINT é 2'nd FEED Keyboard functions Key Label ON Key Function Turns the instrument On. Hold activated until the sign on message appears in the Display. OFF Turns the instrument Off. Terminates all activity and powers off. 2'nd Selects the keyboard function marked with black. First press and hold <2'nd> and then press one of the black functions.
Warning for full Test log (can be disabled) Warning for pour measurement conditions CALIB ZERO Activates calibration measurement. The result is stored in the Test Log. Activates instrument zeroing measurement. The result is stored in the Test Log ENTER Activates selected function, accepts changed settings and confirms choices. CANCEL Cancels selected function or menu and return to top control level displaying the latest Rl result. PRINT Outputs latest measurement result on printer.
Result Printout Rl Printout The Rl result printout showing the measured Rl, the date and time for the measurement, the instrument status code and a R# number showing the number of measurements in the Rl log. The Rl result printout can only follow after a measurement performed with the key. Rl Printout with Measurement ID If the measurement ID has been set to anything other than 6 white space then the ID is printed along with a serial number showing the number of measurement done with that ID.
Test Printout The Test Printout showing the measured Rl, the date and time for the test, the related status code and a T# number showing the number of measurements in the Test log. The test printout can only follow after a measurement performed with the <2'nd> + key. Signal levels and battery conditions are measured during the measurement and printed.
Zero Printout The printout after a Zero measurement showing the measured Zero Signal in % of the nominal signal, if the zero signal is within a specified limit OK is printed, if the zero signal becomes high a warning is printed. A T# number showing the number of measurements in the Test log and the date and time for the measurement, The Zero printout can only follow after a measurement performed with the <2'nd> + key.
Functions and Menu system Rl Calibration (Activate with the key) LCD Display Explanation. Rl Normal Cal. Enter To Start Performs instrument calibration. opens Rl Calibration sub menu. Mount Normal Enter When Ready The user is requested to place his Rl-Normal in the LTL2000 instrument. Press when it is mounted correctly. Calibrating Please wait Measures Rl on the mounted Rl-Normal. Rl Normal 146 Enter=OKêé=edit The display shows the measured Rl value.
Test Log (Select with the
é to Change Press é to disable to accept. Clear Top Log (Activate with the <é> key after a Rl measurement) LCD Display Explanation. Clear Top Log? Enter to Confirm Removes the newest measurement from the Rl Data Log. Confirm the removal with the key. Clear Top Log? No Data in Log! This message is shown when the Rl Data Log is empty. Rl:..
Date and Time (Activate with the
Status (Select with the
The amount of free log entries in %. Test Log Full or Free T_Log: 87.5% A warning is given if the Rl Test Log has run full. This means that it contains approx. 100 test readings, and that no new Test measurements can go into the log. The log will have to be emptied and cleared before this warning goes away. Also the Test number in the printout will not change until the test log is cleared. The amount of free testlog entries in %. LTL2000 rev. 2.0 The LTL2000 instrument ID and revision level.
LTL2000 Command set The LTL2000 is equipped with a serial communication port primarily for log data acquisition, calibration and test, however all normal LTL2000 functions can be controlled from this interface.
LTL2000 command set Command Parameter DT cont. Response VBat Lamp Off: VBat Lamp On: Status code: Meaning Battery voltage with min. load Battery voltage with max. load Actual Status code 12.21 V 11.30 V 0 00000000 FV none II none Y N Initialise Instrument settings [Y/N] Initialising Instrument.
LTL2000 command set Command Parameter Response Meaning LS none Rl DataLog: 6 data points. 99.56% free Rl TestLog: 3 data points. 98.
LTL2000 command set Command Parameter Response Meaning LT none LTL2000 Test Log Dump: 1997 Mar 27 10:01:03 3 entries 98.80% free Date Time Rl Lamp Idle Load Status Mode Y:M:D H:M:S mcd/m2/lx On Off [v] [v] # [Z,C,T] 1997-03-27 10:00:34 -1 12.0 9.5 12.2 11.3 0 Z 1997-03-27 10:00:45 146 162.9 9.6 12.2 11.3 0 C 1997-03-27 10:01:03 146 162.3 9.6 12.2 11.
LTL2000 command set Command Parameter Response Meaning RL none *** Rl Measurement *** 1997 Mar 27 10:00:59 Rl: 146 (mcd/m2)/lx Status Code: 0 00000000 Performs a normal Rl measurement. Displays measurement date and time, the Rl result and the Status code RN none Rl_Factor = 2.312 Rl_Normal = 138 Calculated Rl factor Rl calibration value 150 (Rl Normal) Rl_Factor = 2.
LTL2000 command set Command Parameter Response Warning: Low VBat Meaning Warning for low battery voltage TI none 10.0.0 1997 Mar 27 16:45:51 1997 Mar 27 10:00:00 Real time clock Date and Time New Time (Date unchanged) TO none Sensor Off Turn sensor off (power off) VA none new setpoint Low VBat alarm: 11.0 V Low VBat alarm: new value V Setpoint for low bat warning New set point for low bat warning VB none VBat =12.
LTL2000 command set Command cont.
SECTION 4 MAINTENANCE General care The Retrometer is constructed for outdoor use in ordinary good weather conditions. It will stand moist weather with wet roads, but caution must be taken against rain or splashes and dirt from traffic. The LTL2000 Retrometer is an optical instrument and shall be handled as such. Avoid shock and vibration if possible. Note Keep dust/protection window and light trap clean Protection window The protection window is located in the optical unit, see Appendix C - figure 23.
Fuses Fuses, two pieces, are placed at the rear of the instrument. The charging fuse protects the battery against short circuit and other errors in the charging connector, charger or charging system. The battery fuse protects battery and electronics against short circuit and other errors in the electronic system. Always renew a blown fuse with one of equal rating. To change a fuse carefully unscrew the plastic cap fuse holder by using eg a coin.
Light trap Zero signal is simulated by a light trap made of two glossy and black plastic sheets mounted in an acute angle. If clean this will provide very efficient light absorbing device. The light trap is the tilted black plastic sheet and the area below. The light trap is a part of the base frame. The base frame is also used for transport protection. It is necessary to disassemble the light trap to clean it efficiently. This is easily done as shown in Figure 9.
calculates the calibration factor. This process is fully automatic and if the calibration routine is followed precisely the Retrometer will now display 'True' Rl. Always store the reference calibration unit in a dry and clean environment. At regular intervals the traceable calibration value must be transferred from the reference calibration unit to the control calibration unit. See also section 1: Calibration and section 3: Functions and Menu system and Command set.
Printer The printer is a high speed high quality Mini Thermal Printer. It uses 57.5 mm thermal paper (type KF50). It has only a few moving parts and does not require any special or periodic maintenance. Replacing the paper is easily done by first pushing the spring loaded transparent cover downwards to disengage it from the upper black part, let it swing down and insert a new paper roll. A handwheel makes it easy to insert the paper. Close the cover in reverse order.
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APPENDIX A COMMUNICATION FACILITIES RS-232C specification The LTL2000 is equipped with a communication facility that enables the use of a simple data terminal or an ordinary PC type computer for control of LTL2000 functions and for log data acquisition. The computer or terminal connects to the LTL2000 using a communication cable fitted with a 9 pin male D-Sub connector at one end and a 9 or 25 pin connector at the other end. The electrical connections meet the EIA/TIA-232E and CCITT V.28 specifications.
Connections in the 9 pin D-Sub connector. pin # Function Signal Direction 3 Receive Data Data to LTL2000 2 Transmit Data Data from LTL2000 5 Signal Ground Signal Ground Connection example #1. PC with 25-pin D-Sub communication port.
Connection example #2. PC with 9 pin D-Sub communication port. Cable connections: PC Port DTE pin name LTL DTE 1 CD X 2 RxD -- 2 3 TxD -- 3 4 DTR X 5 SG -- 6 DSR X 7 RTS X 8 CTS X 9 RI X 9-pin female D-SUB 5 9-pin male D-SUB As it can be seen, the interconnections have been held to an absolute minimum, and in some rare situations there will have to be established additional connections on the PC side. Please refer to your PC manual for further information.
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Command format All LTL2000 commands are built using the following template. Command (one ore more letters) Delimiter(one ore more spaces, optional) Parameter (Integer or Real number, optional) Command End (Carriage Return, mandatory) Example #1: The user wants to see how the Automatic Off timer is set and then change the value to 120 seconds. The command and the response sequence look like this. Ot Automatic Off Timer = 300 sec. Ot 120 Automatic Off Timer = 120 sec.
APPENDIX B Special Status Printouts. The LTL2000 can print a special status at power up showing all internal settings and values generated by the different functions. The status printout is activated by holding the keys <2'nd> and activated during power up. Once the print process has started release all keys and wait for the completion. The print process can only be turned off with the key.
Initial Status After executing a ZERO function the status will look like this. It shows that no Zero measurement has been executed and also no Calibration. The values for the highvoltage (VPMT) and battery voltage are set to their default values. The Data log status is shown. The special status shows the setting for the MODE Switch, the measurement counts for noise reduction, the automatic off timer, the actual voltage on the battery, the date and time and finally the firmware revision # and creation data.
Status after first Zero After executing a ZERO function the status will look like this. It shows that the Zero measurement has been executed and when this was done. No calibration has been done yet. The values recorded during the zero measurement, the system leak, the dark signal and the offset signal are listed.
Status after Calibration After executing a Calibration function the status will look like this. Data from the Calibration measurement is added to the list. Also the calculated Rl Factor is added to the list. It can be seen that the data from the calibration measurement went into the Test Log.
Status after Rl measurement After executing a Normal Rl Measurement the status will look like this. Data from the Rl measurement is added to the list. It can be seen that the data from the Rl measurement went into the Data Log.
Status after a Test measurement After executing a Test Measurement the status will look like this. The values from the Test measurement are added to the list. It can be seen that the data from the Test measurement went into the Test Log.
APPENDIX C SPECIFICATION General Characteristics Illumination angle ............................................................................................................... 1.24º Observation angle.............................................................................................................. 2.29º Equivalent observer distance...............................................................................................30 m Observation angular spread ....................................
Environmental Characteristics Temperature: Operating.............................................................................0ºC to + 45ºC (32ºF to +114º F) Storage *) ........................................................................... -15ºC to + 55ºC (5º F to +131º F) Humidity............................................................................................................ Non condensing *) Battery must be fully charged Mechanical Characteristics Max. length.........................
Dimensional drawings DELTA LTL2000 Retrometer 47
Instrument Layout.
Calibration Unit Placement Graphics. The graphics show the Calibration Position this is the correct position and orientation for the calibration unit to obtain optimal calibration precision. The Rear Test Position (near the tower) and the Front Test Position is used to verify that the instrument operates as specified over the entire measurement area.
