Instruction Manual LAS MkII • Scintillometer
Important User Information . Dear customer, thank you for purchasing a Kipp & Zonen instrument. It is essential that you read this manual completely for a full understanding of the proper and safe installation, use, maintenance and operation of your new LAS MkII Scintillometer. We understand that no instruction manual is perfect, so should you have any comments regarding this manual we will be pleased to receive them at: Kipp & Zonen B.V. Delftechpark 36, 2628 XH Delft, - or P.O.
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Declaration of Conformity . We Kipp & Zonen B.V. Delftechpark 36, 2628 XH Delft P.O.
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Table of Contents . . Important User Information3......................................................................................................................................................................................... . 3 Declaration of Conformity ............................................................................................................................................................................................... 5 Table of Contents ...........................
. . . 4. Software installation and configuration ................................................................................................................................................. 41 4.1 Installing the EVATION software package ............................................................................................................................................................. 41 4.1.1 System requirements ................................................................................
1. Introduction . Throughout this manual the following symbols are used to indicate to the user important information. General warning about conditions, other than those caused by high voltage electricity, which may result in physical injury and/or damage to the equipment or cause the equipment to not operate correctly. Note Useful information for the user 1.
1.2 Key parts of the LAS MkII Scintillometer 1.2.1 Transmitter and receiver The drawing shows the key common parts of the LAS MkII transmitter and receiver: 1 Sun shield fitted to the mounting for the alignment telescope 2 Tilt (vertical) adjustment screws 3 Pan (horizontal) adjustment screws 4 Transmitter window, with heater and Fresnel lens behind 5 Drying cartridges 6 Baseplate 1 4 2 5 2 3 5 2 3 6 6 1.2.
. 1.2.
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2. Installation . Please follow the instructions in this section carefully for the mechanical and electrical installation of the LAS MkII scintillometer. Do not turn on power to the transmitter or receiver until instructed to do so. Ensure that fixings and mountings are securely tightened when instructed to do so. 2.1 Included with the product Check the contents of the shipment for completeness (see below) and note whether any damage has occurred during transport.
. 2.1.1 The transmitter The transmitter housing contains a very efficient, eye-safe LED operating at 850 nm wavelength in the near-infrared region. The LED mounting is axially adjustable to position it at the focus of a Fresnel collimating lens. The near-parallel beam is output through a glass window with an aperture diameter of 150 mm. There is a self-regulating heater for the window that can disperse rain, dew, frost and snow. Electronics pulse the LED at 6.
. 2.1.2 The receiver The beam from the transmitter enters the receiver through a glass window with an aperture diameter of 150 mm. There is a self-regulating heater for the window that can disperse rain, dew, frost and snow. A Fresnel lens focusses the 6.5 - 7 kHz pulsed radiation onto a very sensitive large-area photodiode detector with a thin-film optical filter that only transmits radiation in a waveband around 850 nm, blocking ambient light from reaching the detector.
. 2.1.3 Alignment telescopes Each transmitter and receiver has a telescope, individually adjusted to align with its optical axis, and each telescope is labelled accordingly. These telescopes attach by clamps to mounting rails on the tops of the transmitter and receiver housings and enable alignment of the transmitter and receiver at long path lengths. They are not completely weatherproof and should be removed after alignment and replaced by the sun shields.
. 2.1.5 Aperture restrictors The full beam aperture of 150 mm enables operation over path lengths from 250m to 4.5 km, depending upon the atmospheric conditions. For shorter path lengths, from 100m to 1 km, restrictors with apertures of 100 mm are fitted in front of the windows of the transmitter and receiver. 2.1.6 Power cables Two 10 m long cables with 4-pin waterproof plugs are provided for the transmitter and receiver 12 Volt DC power inputs. 2.1.
. 2.1.9 Allen keys Two 3 mm hexagonal Allen keys are supplied for fitting the transmitter and receiver telescopes and two 4 mm hexagonal Allen keys for fitting the sun shields. 2.1.10 CD-ROM The supplied CD-ROM contains the EVATION software package and this manual as a pdf file. 2.1.11 Desiccant packs Eight spare packs of self-indicating silica gel desiccant are supplied for the drying cartridges of the transmitter and receiver. 2.
2.3 Location and support base When choosing the location for scintillometer measurements care has to be taken that certain requirements are met. 2.3.1 Path orientation and avoiding direct sunlight Avoid locating the transmitter and receiver where direct sunlight may be in their views. The Fresnel lenses will focus the light onto the transmitting LED and the receiving optical filter and photodiode and there is a risk of damage due to overheating.
Full 150 mm aperture 60 h = 50 W/m² h = 100 W/m² h = 150 W/m² h = 250 W/m² h = 300 W/m² h = 400 W/m² 50 Height LAS [m] 40 No saturation 30 20 10 Saturation 0 0 500 1000 1500 2000 2500 3000 3500 4000 4500 Path length LAS [m] Restricted 100 mm aperture 7 h = 50 W/m² h = 100 W/m² h = 150 W/m² h = 250 W/m² h = 300 W/m² h = 400 W/m² 6 Height 0.1 m-LAS [m] 5 No saturation 4 3 2 1 Saturation 0 0 100 200 300 400 500 600 700 800 900 1000 Path length 0.1 m-LAS [m] .
. 2.3.3 Effective beam height Determine the effective height of beam of the LAS MkII (zLAS) along the path precisely. The surface sensible heat flux (H) derived from the structure parameter data is very sensitive to the height (see Appendix A). When the area is relatively flat and the beam is parallel to the surface the effective height is easy to determine (ztransmitter = zreceiver = zLAS).
. The PBL is directly influenced by the earth’s surface and its depth varies between roughly 100 m and 2 km. In general the PBL increases during the day, when the Earth’s surface is heated by the sun, and decreases again during the night. Within the SL the variation of fluxes (such as the sensible heat flux H and latent heat flux Lv E) is negligible with respect to the magnitude of their value at the surface.
2.4 Mounting The LAS MkII can only function properly when the transmitter and receiver are precisely optically aligned. By mounting the scintillometer on a stable support, signal loss and regular re-alignment procedures will be avoided. Vibrations in the mounting structure must be prevented, which can lead to overestimated Cn2 values. This particularly applies to masts or towers that can bend and vibrate in the wind. Mount the LAS MkII transmitter and receiver on stable and vibration-free supports.
2.5 Electrical and data connections There are two waterproof connectors located on the rear panel of the transmitter and four on the rear panel of the receiver. 2.5.1 Power connector The transmitter and receiver are each provided with a 4-pin waterproof plug fitted to a 10 m long cable that is terminated in tinned wires, for 12 Volts DC (nominal) power to the instrument and heater. Transmitter and receiver power connector and cable Pin number Wire colour Function Value 1 red instrument power + 9.
. 2.5.3 Receiver Analogue signal connector The receiver is provided with a 4-pin plug for analogue signal outputs, fitted to a 10 m long yellow cable that is terminated in tinned wires. Receiver analogue signal connector and cable Pin number Wire colour Function Value Impedance 1 red Log UCn2 signal + 0 to 2 V 10-17 to 10-12 m-2/3 680 Ω 4700 pF 2 blue 6.
. 2.5.5 Receiver meteorological sensor kit connector The 8-pin connector marked ‘Sensors’ must only be used with the accessory meteorological sensor kit. The 12 VDC output must not be used to supply other equipment.
2.6 Aperture restrictors for short range applications In case the LAS MkII is required to operate over short distances the aperture diameter of the transmitter and receiver can be reduced to 100 mm using the supplied restrictors. The LAS MkII can then be used over path lengths from 100 m to 1 km. To fit the restrictors proceed as follows and shown in the diagram below: 1. Remove 3 of the 6 retaining screws of the transmitter and receiver windows 2. Replace the screws by the nylon spacers 3.
2.7 Using the display and key-pad The waterproof display and menu navigation keys located on the rear panel of the LAS MkII receiver allow for complete instrument configuration and control without the need for additional computers, cables and software. This section describes the basic procedure for navigating through the menus, changing and confirming settings. Note The complete menu structure of the LAS MkII scintillometer can be found in Appendix C.
. For example to change the path length setting from 110.0 m to 1250.0 m the following actions need to be performed: 2. path length 0110.0 m 2. path length 1110.0 m 2. path length 1110.0 m 2. path length 1210.0 m 2. path length 1210.0 m Press 4x (to increment from 1 to 5) 2. path length 1250.
2.8 Configuration for measurement The table below shows the sub-menus contained within Menu 2, Configuration. These sub-menus require setting up before, or during, installation. To configure the LAS MKII receiver before installation refer to the ‘power up receiver’ section 2.9.4. Note The complete menu structure of the LAS MkII scintillometer can be found in Appendix C. Sub-menu 1. Installation 2. Advanced 3. Sensors 4. DataLogger 5. Interface Note Sub-menu item Function Range Default 1.
. 2.8.1 Setting parameters to measure Cn2 Cn2 is measured using the following general algorithm: Cn2 = 1.12 σlnI2 D 7/3 L-3 Where; D is the aperture diameter of the LAS MkII, L is the distance between the transmitter and the receiver (the path length) and σlnI2 the measured variance of the natural logarithm of intensity fluctuations. The parameters for aperture and path length must be set in the receiver.
. 2.8.4 Data Logger Configure the following data logger settings; date, time, sleep time, wakeup time, log-interval and send interval. The wakeup time defines the start of the operational mode. When the operational mode is active the LAS is measuring and logging data; the receiver heater is turned on when the temperature of the receiver is below the ‘operating temperature’ in the heater menu.
2.9 Installation and optical alignment The alignment of the LAS MkII at the measurement site is an iterative process for establishing the optimum signal strength for horizontal line-of-sight transmission. The different steps are summarized below. We recommend practicing the alignment procedure at a short range (~ 250 m) before installation at longer distances. The transmitter and receiver can be rotated around both vertical and horizontal axes.
. 2.9.2 Installing the transmitter and receiver 1. Install the transmitter and receiver of the LAS MkII at their selected positions. 2. The bolts used to fix the baseplates to the tripods or other supporting structures are fastened by hand, so that the transmitter and receiver can still be turned around their vertical axes. 3. Clamp the telescopes to the rails on the tops of the transmitter and receiver using the 4 mm hexagonal Allen keys.
. If a hardware error message occurs, try turning off the power and the restarting the receiver. If the error persists, make a note of the code and contact support@kippzonen.com 3. A configuration error message will be displayed if one or more of the configuration parameters stored in the memory are not correct.
. 7. Repeat steps 2 to 8 until the best transmitter optical alignment is achieved. 8. Tighten the transmitter adjustment screws, checking that the signal strength has not changed. . Left Signal level [mV] Beam width Right Center beam > UDEMOD * 4 0000.0 mV 0 2.9.6 Receiver optical alignment Note It is very important to follow this procedure carefully because the data is not reliable when the edges of the beam are too close to the receiver or transmitter aperture. 1.
. 2. Screw on the cover of the power adjustment knob. Hand-tighten only to avoid damaging the o-ring seal. 3. The optical alignment is now complete. Go back to the View RealTime menu and sub-menu 3 (Cn2). The LAS MkII should now be measuring and logging data according to the configuration set in section 2.8. . Note It is possible that the transmitter or receiver is not now aligned with the centre of the crosshairs of its telescope.
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3. Accessories 3.1 Meteorological sensor kit The kit is supplied as a cross-arm with cables connected to a junction box, which has a 10 m long yellow cable fitted with a waterproof connector. The junction box contains an air pressure sensor and has a sintered bronze ‘breather’ to the ambient air. Wind speed and air temperature sensors are provided, which must be secured to the cross-arm (the fixing screws are already fitted to the cross-arm) and then connected to the cables.
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4. Software installation and configuration . The LAS MkII scintillometer can be configured in two ways; using the built-in display and keypad of the receiver or through the included EVATION software package. Configuring the receiver using the display and navigation keys has been described in section 2.8. This section describes the LAS MkII configuration using EVATION.
. 4.1.4 Selecting a data folder EVATION stores all scintillometer data and processing settings in a predefined folder structure.
. When LAS II is selected, the following options will become available; Communication, Installation and Instrument. For all other LAS types these options are not available. 4.2.2 Communication Select the serial communications port of the computer that the LAS MkII is connected to. Set the baud rate, parity and number of databits to match the LAS MkII receiver settings (the default setting is 4800 bps with no parity and 8 databits). 4.2.3 Installation Configure the site-specific parameters.
. Parameter Description Effective height LAS For an even terrain with minimal changes in elevation along the path, the effective height of the beam is relative to the ground For an uneven terrain use the effective height calculator (see Appendix E) Path length The distance between the transmitter and the receiver Air temperature Air pressure Wind speed When unchecked values from the meteorological sensor kit will be used When checked fixed user values can be entered Zero-displacement height See desc
. In the table below the eight different terrain classifications are given. Class Name Roughness length m Landscape features 1 Sea 0.0002 Open water, tidal flat, snow with fetch greater than 3 km 2 Smooth 0.005 Featureless land, ice 3 Open 0.03 Flat terrain with grass or very low vegetation, airport runway 4 Roughly open 0.1 Cultivated area, low crops, obstacles of height h separated by at least 20 h 5 Rough 0.25 Open landscape, obstacles separated by ~15 h 6 Very rough 0.
. 4.2.
. On the main screen the current settings in EVATION and in the LAS MkII receiver are displayed. Any differences between the settings will be indicated by a green indicator next to the parameter. green indicator This screen presents two choices: ‘Update Computer’ : EVATION will be updated with the settings from the LAS MkII receiver. ‘Update Instrument’ : The LAS MkII receiver will be updated with the settings from EVATION. After pressing an ‘Update button it will change to display ‘Stop Update’.
Parameter Description Latitude The latitude of the installation site Effective height LAS For even terrain along the scintillometer path, the effective height is the height of the beam relative to the ground For an uneven terrain please use the Effective Height Calculator Height wind speed anemometer The height of the anemometer above the surface Height upper temperature sensor The height of the upper temperature sensor above the surface Height lower temperature sensor The height of the lower tem
5. Operation and measurement . After completing the software installation and configuration the LAS MkII is ready for operation. 5.1 Collecting digital data The data from the LAS MkII receiver can be obtained using the EVATION software. EVATION has the functionality to collect data from the receiver’s internal data logger and the real-time data display. . 5.1.
. Parameter Description Read new Only new data is downloaded Read all All data in the memory is downloaded Manual start Download data at the user’s request Automatic start Download new data records as soon as they are available in the receiver Start download Start the data download process Date and time settings Four options for setting the LAS MkII internal clock from a computer: Local time without DST Local time with DST Greenwich Mean Time (UTC) Manual time (user defined date and time) Set
5.2 Data file format Three types of files are downloaded by EVATION from the LAS MkII internal memory: • Data files • Configuration change logs • Error logs This section describes the information and format of these file types. The file format is fixed and cannot be changed.
5.3 Collecting analogue data The Cn2 values can be computed from the output signal (UCn2) using the following equation: Cn2 = 10 (2.5• U Cn2 -17) Cn2 = structure parameter of the refractive index of air [m-2/3] UCn2 = log scaled [V] Cn2 signal For example if UCn2 = 0.5 V, then Cn2 = 1 · 10-16 m-2/3 Cn2 value vs. LAS analogue output 1 · 10-12 Corresponding Cn2 value [m-2/3] 1 · 10-13 1 · 10-14 1 · 10-15 1 · 10-16 1 · 10-17 0 0.5 1 1.5 2.
. 2. Calculate Cn2 immediately after each measurement cycle (e.g. every 1 second, 1 Hz) and derive the interval-averaged Cn2 (e.g. 10 minute averages) from the instantaneous Cn2 values. Because the Cn2 values are too small to store in most conventional data acquisition systems (~ 1·10-16) The following calculation needs to be performed by the data logger: PUCn2 = 10 UC ∧2.5 100 2 n PUCn2 vs. LAS analogue output 1000 Corresponding PUCn2 value 100 10 1 0.1 0.01 0 0.5 1 1.5 2.
5.4 Processing data files EVATION can process data files retrieved from the LAS MkII receiver data logger, LAS MkII ET Systems and correctly formatted data files from third party data acquisition systems. 5.4.1 Setting input parameters In order to process the scintillometer data a number of parameters need to be set. Select the ‘Process Data’ option from the Configuration menu. On the first page, set all the parameters to match the installation. All parameters need to be filled in.
. In the ‘Input’ tab details on the data files must be selected. If the data files have been generated by the Kipp & Zonen LAS MkII ET System and its COMBILOG data logger, check the ‘Standard Input File’ box and the default ET System settings will be used. If LAS MkII has been selected as the scintillometer model in section 4.2.1, the correct file format will be set automatically.
. To check whether the settings are correct, press the ‘Quick Test’ button to select a data file to be viewed. The spread-sheet screen below shows an overview of how the data is read based on the settings. In case the spread sheet is empty, an error has been made in defining the date/time format or an incorrect assignment of column numbers. Using the ‘Save’ button, the configuration for your data files can be saved.
. 5.4.2 Setting output parameters In the ‘Output’ tab, the parameters which need to be included in the output files are chosen. See the image below for more information.
. Press the ‘Process’ button to start the data processing, the progress bar will indicate the current status. When the process is finished, an overview is given of the resulting output files. When the files are selected, the graph will show the data contained within them. The processed data files are placed in the ‘Output’ folder.
5.5 Diurnal patterns This section shows some typical day and night (diurnal) patterns for both Cn2 and energy fluxes. 5.5.1 Diurnal Cn2 patterns The diurnal pattern of values for Cn2 differs depending on atmospheric conditions. However, for a typical pattern the most significant features are the two dips in Cn2 values which occur around sunrise and sunset. These dips indicate the transition Structure parameter refr. index of air [m-2/3] between stable and unstable fluxes in the atmosphere.
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6. Maintenance and recalibration 6.1 Internal calibration features The LAS MkII receiver has built-in diagnostics and calibration features to ensure correct operation of the system. These functions can be accessed using the navigation keys and display. 6.1.1 Checking Cn2 processing Follow the following steps to check the internal processing of Cn2 values. Main Menu → 2. Configuration → 1. Installation → 1. Aperture → set to 152 mm → Confirm Entry: YES Then; 2. Configuration → 1. Installation → 2.
6.2 Maintenance and inspection intervals To ensure that the quality of the measurements is of a high standard, care must be taken with the maintenance of the LAS MkII. Regular cleaning of the transmitter and receiver windows and checking the optical alignment will prevent unnecessary signal attenuation and data loss. Regularly check the desiccant to prevent moisture inside the transmitter and receiver. Periodically check the condition of all cables and connectors.
. 3. Remove the caps from the ends of the cartridges and safely dispose of the used silica-gel. Refill with fresh desiccant, and refit the end caps to the cartridges. 4. Make sure that the o-ring seals and their seats in the housing are clean, grease with Vaseline if it they are dry. Refit the drying cartridges. Note Screw in the drying cartridges hand-tight only, to avoid distorting the o-ring seals. Desiccant refill packs are available from Kipp & Zonen. One pack is sufficient for one cartridge refill.
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7. Specifications . Note Kipp & Zonen reserves the right to make changes to specifications without prior notice. 7.1 Specifications of LAS MkII transmitter Parameter Value Operating temperature -20 °C to +50 °C Humidity 0 to 100 % RH, IP 65 Voltage 12 VDC nominal (9.6 to 18 VDC) Power 6 W maximum with heater off 54 W maximum with heater on, typical 26 W Window heater Self-regulating at approx.
7.2 Specifications of LAS MkII receiver Parameter Value Operating temperature -20 °C to +50 °C Humidity 0 to 100 % RH, IP 65 Voltage 12 VDC nominal (9.6 to 18 VDC) Power 3 W maximum with heater off 51 W maximum with heater on, typical 23 W Window heater Self-regulating at approx.
8. Trouble shooting . The LAS MkII is designed for long periods of operation with little operator maintenance. However, if a problem occurs that cannot be corrected using the standard operating information supplied in the preceding sections of this manual, use the information below to identify and solve the problem. There are no user-serviceable parts within the LAS Mk II and the transmitter or receiver must not be opened without the agreement and instruction of Kipp & Zonen. 8.
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9. Customer support . If you require any support for your Kipp & Zonen product please contact your local representative in the first instance. The information can be found in the ‘Contact’ section of our website at http://www.kippzonen.com/?page/74152/Contact.aspx Alternatively, you can contact us directly at support@kippzonen.com.
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Appendix A. Theory of the scintillation technique . When an electro-magnetic (EM) beam of radiation propagates through the atmosphere it is distorted by a number of processes. These processes remove energy from the beam and lead to attenuation of the signal. The most serious mechanism that influences the propagation of EM radiation is small fluctuations in the refractive index of the air (n). These refractive index fluctuations lead to intensity fluctuations, which are known as scintillations.
. AT and AQ are functions of the beam wavelength and the mean values of temperature, absolute humidity, and atmospheric pressure and thus represent the relative contribution of each term to Cn2. In the visible and near-infrared wavelength region of the EM spectrum AT and AQ are defined as follows (Andreas, 1988): AT = -0.78⋅10-6 P +0.126⋅10-6 RV Q T AQ = -0.126⋅10-6 RV Q where Rv is the specific gas constant for water vapour (461.5 J K-1 kg-1).
. where ρ is the density of air (~1.2 kg m-3), cp the specific heat of air at constant pressure (~1005 J kg-1 K-1), kv the von Kármán constant (~0.40), g the gravitational acceleration (~9.81 m s-2) and u* the friction velocity. The universal stability function fT is defined as follows for unstable (day-time, LMO < 0) conditions: fT zLAS - d z -d = cT1 1 - cT2 LAS LMO LMO -2/3 LMO < 0 where cT1 = 4.9 and cT2 = 6.
. For most day-time (unstable) conditions and when the LAS MkII is installed relatively high above the surface (zLAS MkII > 20 m) the contribution of the friction velocity is relatively small. For these conditions the free convection method can be applied: Hfree = ρcp b (zLAS - d) g T 1/2 (CT2) 3/4 where b is an empirical constant: (b = 1 cT1 3/2 kv cT2 0.48) This free convection approach provides a simpler method to determine H (in this case termed ‘Hfree’) directly from CT2 without knowing u*.
. Summary of the steps to derive surface sensible heat flux, H, from LAS MkII measurements: Structure parameter of refractive index of air Cn2 [m-2/3] Air temperature T [K or °C] Atmospheric pressure P [Pa] Bowen ratio B [ß] Structure parameter of temperature CT2 [K2 m-2/3] Air temperature T [K or °C] Height LAS Z-LAS [m] Zero-displacement height d [m] Roughness length zo [m] Gravitational acceleration g [m/s²] Air density ρ [kg/m³] Wind speed u [m/s] Height wind speed z-u [m/s] Sensible heat flu
. Finally, when additional net radiation (Q*) and soil heat flux (Gs) data are available, the latent heat flux LvE (or actual evaporation) can be estimated applying the surface energy balance equation: Q* = H + LvE + Gs Below is an example of a time series of net radiation, soil heat flux, sensible heat flux and latent heat flux measurements.
Appendix B. List of symbols and abbreviations . . .
. . CFL Constant Flux Layer In general, in the lowest 10 % of the PBL the surface fluxes are constant with height and this part of the PBL is also known as the Constant Flux Layer of the Surface Layer. Therefore fluxes measured in the SL can be considered as being representative fluxes for the heat and mass exchange processes between the atmosphere and the surface.
Appendix C. LAS MkII menu structure . Below is an overview of the menu structure of the LAS MkII scintillometer. 1. View RealTime 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
. 4. Data Logger 1. 2. 3. 4. 5. 6. 7. Set or show the data logger configuration Set Date Set Date Set Time Set Time Wakeup Time Set or show time to start to measure and log Sleep Time Set or show time to stop measure and log Log Interval Set average & log interval of measurements Send Interval Set interval to send data to a computer «Back Go one submenu level back (yy/mm/dd) (hh:mm:ss) (hh:mm, 99:99 =Off) (hh:mm, 99:99 =Off) (0 to 29999 s, 0=Off) (0 to 29999 s, 0=Off) 5. Interface 1. 2. 3. 4. 5. 6. 7. 8.
Appendix D. Configuration error messages . A configuration error message will be displayed if one or more of the configuration parameters stored in the memory are not correct. The messages are explained as follows: Checksum error The EEPROM-signature was not found. The EEPROM -signature is not set when the EEPROM is empty or when the data stored is lost or corrupted. If this error appears the EEPROM must be reconfigured. Please contact support@kippzonen.com.
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Appendix E. Effective height calculator . The accuracy of the fluxes of sensible heat and evapo-transpiration depend strongly upon the mean height of the LAS MkII optical beam above the surface. In case the area is completely flat the average beam height can be easily derived from the transmitter height and the receiver height. In case the area is complex it becomes more difficult to determine the effective height of the beam.
. The effective height of the LAS beam can then be calculated as shown below.
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Our customer support remains at your disposal for any maintenance or repair, calibration, supplies and spares. Für Servicearbeiten und Kalibrierung, Verbrauchsmaterial und Ersatzteile steht Ihnen unsere Customer Support Abteilung zur Verfügung. Notre service 'Support Clientèle' reste à votre entière disposition pour tout problème de maintenance, réparation ou d'étalonnage ainsi que pour les accessoires et pièces de rechange.
