Kipp & Zonen LAS MkII ET System User manual

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Instruction Manual
LAS MkII ET System

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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 ET System.
Please read this manual in conjunction with the instruction manual for the 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. Box 507, 2600 AM Delft,
The Netherlands
T: [phone]
F: [phone]
[email protected]
www.kippzonen.com
Warranty and liability
Kipp & Zonen guarantees that the product delivered has been thoroughly tested to ensure that it meets
its published specifications. The warranty included in the conditions of delivery is valid only if the
product has been installed and used according to the instructions supplied by Kipp & Zonen.
Kipp & Zonen shall in no event be liable for incidental or consequential damages, including without
limitation, lost profits, loss of income, loss of business opportunities, loss of use and other related
exposures, however used, arising from the faulty or incorrect use of the product.
Modifications made by the user may affect the instrument performance, void the warranty, or affect the
validity of the CE declaration, or other approvals and compliances to applicable International
Standards.
Copyright © 2018 Kipp & Zonen B.V.
All rights are reserved. No part of this publication may be reproduced, stored in a retrieval system or
transmitted, in any form or by any means, without authorisation by Kipp & Zonen.
Kipp & Zonen reserves the right to make changes to this manual, brochures, specifications and other
product documentation without prior notice.
Manual document number: V1806
Publication date: 1st June 2018

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TABLE OF CONTENTS
Important User Information ............................................................................................................................................................2
Table of Contents ..................................................................................................................................................................................3
1Introduction.....................................................................................................................................................................................5
1.1 Product overview ............................................................................................................................. 5
1.2 Key parts of the LAS MkII ET system ..............................................................................................6
2Installation .......................................................................................................................................................................................7
2.1 Included with the system ................................................................................................................7
2.1.1 LAS MkII scintillometer.................................................................................................................7
2.1.2 Meteorological sensors and mast................................................................................................8
2.1.3 NR Lite2 Net Radiometer............................................................................................................10
2.1.4 COMBILOG Data Logger .............................................................................................................10
2.1.5 Additional items .........................................................................................................................10
2.2 Site selection procedure................................................................................................................11
2.2.1 LAS MkII scintillometer ..........................................................................................................11
2.2.2 The meteorological sensors and mast..................................................................................11
2.3 Power supply..................................................................................................................................11
2.4 Assembling the meteorological mast and sensors ......................................................................12
2.4.1 The mast.................................................................................................................................12
2.4.2 The mounting arms and sensors ..........................................................................................13
2.5 Installing the mast.........................................................................................................................14
2.6 Mounting the data logger enclosure ............................................................................................15
2.7 The soil heat flux sensors.............................................................................................................16
2.8 Sensor overview .............................................................................................................................17
2.9 Connecting the sensors.................................................................................................................18
2.10 Installing the scintillometer.......................................................................................................21
3ACCESSORIES ...............................................................................................................................................................................21
4SOFTWARE INSTALLATION AND CONFIGURATION...............................................................................................22
4.1 EVATION software..........................................................................................................................22
4.2 LAS MKII configuration ..................................................................................................................22
4.3 Effective height calculator.............................................................................................................22
4.4 COMBILOG support software ........................................................................................................22
4.4.1 Setting communication parameters ......................................................................................22
4.4.2 Communicating with the COMBILOG ....................................................................................23
4.4.3 Original COMBILOG module settings and programs............................................................24
5OPERATION AND MEASUREMENT....................................................................................................................................24
5.1 REAL-TIME MONITORING OF MEASUREMENTS ..............................................................................24
5.1.1 Via COMBILOG support software...........................................................................................24
5.1.2 Via the COMBILOG display.....................................................................................................25
5.2 Calibration coefficients .................................................................................................................25
5.3 Data files ........................................................................................................................................26
5.4 Combilog 1022 configuration file for LAS MkII ET system..........................................................27
6MAINTENANCE AND RECALIBRATION...........................................................................................................................28
6.1 Check the power is on...................................................................................................................28
6.2 Check COMBILOG date and time...................................................................................................28
6.3 Check sensor signals.....................................................................................................................28

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6.4 Check sensor condition.................................................................................................................28
6.5 Check cables and connections......................................................................................................28
6.6 Check condition of the tower, guy wires and anchoring.............................................................28
6.7 Download the data from the COMBILOG: .....................................................................................29
6.8 Check the LAS MkII Scintillometer ................................................................................................29
7SPECIFICATIONS.........................................................................................................................................................................29
8TROUBLE SHOOTING ...............................................................................................................................................................30
9CUSTOMER SUPPORT ..............................................................................................................................................................31
SYSTEM Installation form ............................................................................................................................32
General Information..................................................................................................................................32
Weather station sensors / data logger channel.......................................................................................32
LAS MKII Scintillometer .............................................................................................................................33
Effective Height of LAS MKII Scintillometer..............................................................................................34

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1INTRODUCTION
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 Product overview
Note Please read this manual in conjunction with the instruction manual for the LAS MKII
scintillometer.
The LAS MkII ET System (ET stands for evapo-transpiration) is designed for scintillometer-based surface
flux measurements and is specially intended for Earth energy balance and water management studies.
Evapo-transpiration is an important term of the surface energy budget:
sv GELHQ 
*
[W/m2]
where Q*is the available energy, also known as the net radiation (Rn), Hthe sensible heat flux, LvEthe
latent heat flux and Gsthe soil heat flux. In some cases extra storage and/or advective terms can be
added to the surface energy balance. The evapo-transpiration (ET), which stands for the evaporation (E)
from bare soil and the transpiration (T) by vegetation, is related to the latent heat flux (LvE) as follows
v
v
L
EL
ET 
where Lvis the latent heat of vaporisation (the energy required to evaporate 1 kg of water, Lv2.45 
106J kg-1).
This means that ET can be expressed as:
a) an energy flux (LvE) in W/m2, mostly used in used in meteorology, or
b) as a mass flux (ET) in mm/day, mostly used in hydrology, where 1 W/m2is equal to 0.0353 mm
of water per day.
The latent heat flux (LvE), or ET, is an important term in the soil-water balance:
outputinputS
where Sis the change of storage of water in the soil, which is the result of the amount of input into
the soil (due to rainfall or irrigation) minus the amount of loss of water (due to evapo-transpiration,
surface run-off and drainage).
The LAS MkII ET System has been developed to provide area-representative surface fluxes of sensible
heat (H) and latent heat (LvE). A unique feature is the line of sight path-integrating capability of the
large aperture scintillometer. This allows the user to measure area-averaged surface fluxes of sensible
heat at scales from 100 m to 4.5 km, over both homogenous and moderately heterogeneous areas.
Traditional measurement techniques (the eddy-covariance method, flux-profile method, Bowen ratio
method and lysimeters) are point (in-situ) measurements and therefore are less representative of large
areas, particularly the pixel area of satellite instruments.

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1.2 Key parts of the LAS MkII ET system
The LAS MkII ET system consists of four parts; a LAS MKII scintillometer, an extended set of
meteorological sensors with a mast, a data logger in a weatherproof enclosure, and data processing
software to run on a Windows® compatible computer.
The structure parameter of the refractive index of air (Cn
2) measured by the LAS MKII, air temperature,
wind speed, and air pressure, are used to determine the surface flux of sensible heat (H). By adding a
second temperature sensor, net radiometer, and soil heat flux sensors, the latent heat flux (LvE) can be
derived, via
sv GHQEL  *
LvEis the residual term of the energy balance.
The data processing of the LAS MkII ET system is done by the EVATION (evapotranspiration) software
program. This user-friendly program, developed by Kipp & Zonen, processes the raw data to fluxes of
sensible and latent heat.

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2INSTALLATION
Please follow the instructions in this section carefully for the mechanical and electrical installation of
the LAS MkII ET System.
Do not turn on power to the transmitter, receiver or data logger until instructed to do so.
Ensure that fixings and mountings are securely tightened when instructed to do so.
2.1 Included with the system
Check the contents of the shipment for completeness (see below) and note whether any damage has
occurred during transport. If there is damage, a claim should be filed with the carrier immediately. In
the case of damage and/or the contents are incomplete, contact your local Kipp & Zonen representative
or e-mail the Kipp & Zonen customer and product support department at:
[email protected]
Note The LAS MkII is rugged, but it contains sensitive optical and electronic parts. Please keep the
original transport case and packaging to safely transport the scintillometer to measurement
sites or for other shipments.
2.1.1 LAS MkII scintillometer
The following items are included with the LAS MkII scintillometer:
LAS MkII transmitter with pan and tilt adjuster and baseplate
LAS MkII receiver with pan and tilt adjuster and baseplate
2 alignment telescope with detachable mounting, adjusted for each transmitter and receiver
2 sun shield with two fixing screws
2 100 mm diameter aperture restrictor with fixing kit, for transmitter and receiver
1 10 m cable with 4-pin plug for transmitter signal output and receiver analogue connections
1 x 10 m cable with 8-pin plug and 9-pin D-connector for receiver digital communication connections
2 x 10 m cable with 4-pin connector for 12 VDC power input
2 x 3 mm hexagonal Allen keys, for fitting the sun shields
2 x 4 mm hexagonal Allen keys, for fitting the telescopes
1 x USB memory stick containing EVATION software and a pdf file of the LAS MkII instruction manual
8 x spare desiccant packs
1 x GPS antenna with 2 m cable and 8-pin plug, affixed on aluminium mounting arm
1 x aluminium transport case to hold above parts
For a full description of the LAS MKII scintillometer refer to its instruction manual.

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2.1.2 Meteorological sensors and mast
The following items are included with the meteorological sensors and mast:
Temperature sensor x 2, upper and lower
Range
-40 oC to +60 oC
Output
PT-100 (4-wire)
Calibration
0.03ºC 1/10 DIN accuracy
Wind speed sensor
Operating temperature
-25 oC to +80 oC
Range
0 to 60 m/s
Voltage and power sensor
Voltage and power heater
Nominal 12 VDC (~2 mA)
Nominal 12 VDC (max 7 Watt)
Output
Digital 0 to 600 Hz
Wind direction sensor
Operating temperature
-25 oC to +80 oC
Range
0 to 360o
Voltage and power sensor
Voltage and power heater
Nominal 12 VDC (~2 mA)
Nominal 12 VDC (max 7 Watt)
Output
8-bit Gray Code
Air pressure sensor (mounted inside data logger enclosure)
Operating temperature
-25 oC to +70 oC
Range
600 –1050 hPa
Voltage and power
Nominal 12 VDC (~10 mA)
Output
0.3 –4.9 VDC
Soil heat flux sensor
Operating temperature
-30 oC to +70 oC
Range
2000 W/m2

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Output
20 mV
Mast, telescopic
Height
4 m maximum
Guy wires
3 stainless steel wires with securing pins
Baseplate
With socket for mast
Lightning protection
Mast top rod and earth spike
Mounting arms
U-shaped - wind speed and direction sensors
2-sided - upper temperature sensor and NR Lite2
1-sided - lower temperature sensor

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2.1.3 NR Lite2 Net Radiometer
The mast includes a mounting arm for the Kipp & Zonen NR Lite2 net radiometer.
Net radiation sensor, NR-Lite2
Operating temperature
-40 °C to +80 °C
Range
±2000 W/m2
Output
~ ±20 mV
2.1.4 COMBILOG Data Logger
The data logger is fitted in a stainless steel weather-proof enclosure with a clamp for the mast.
COMBILOG 1022 data logger
Stainless steel enclosure, over-voltage input protection, mast mountings
Operating temperature
-20 °C to +60 °C
Supply voltage
10 to 30 VDC
Analogue inputs
8 (16-bit)
Digital I/O
6
Interfaces
RS-232/RS-485/USB/Ethernet
Data storage
7 MB internal RAM, expandable by SD card
Optional
AC to 12 VDC power supply and backup battery
Optional
GSM data modem
2.1.5 Additional items
The data logger is fitted in a stainless steel weather-proof enclosure with a clamp for the mast.
LAS MkII manual, EVATION software and manual (supplied on a USB memory stick with the LAS
MkII scintillometer)
Documentation for the meteorological sensors
COMBILOG support software (supplied on CD-ROM) and manual
NR Lite2 instruction sheet and calibration certificate (supplied with the NR Lite2)
Note Kipp & Zonen reserves the right to make changes to specifications without prior notice.
Note The ET system is not supplied with a relative humidity sensor. A default value (50%) is used in
the EVATION software. Uncertainties in RH have only a small effect on the sensible heat flux and the
evapo-transpiration.

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2.2 Site selection procedure
This section provides information on selecting an appropriate installation site.
2.2.1 LAS MkII scintillometer
For the general installation and site requirements of the LAS MkII scintillometer please refer to its
manual.
For reliable air (Cn
2)and flux (H and LvE) measurements it is important to meet the installation
requirements of the scintillometer. These are:
The LAS MkII transmitter and receiver must be placed on robust and vibration free supports.
Avoid saturation of the signal by installing the LAS MKII at a suitable height (depending upon
surface conditions and path length).
Ensure that the LAS MKII is measuring in the Constant Flux Layer for reliable flux derivations of
the Cn2signal using MOST (depends on surface characteristics).
Pay attention to orientation, installation height and beam height requirements. For detailed
information refer to the LAS MkII instruction manual.
2.2.2 The meteorological sensors and mast
The LAS MKII receiver is supplied with a 10m long cable for connecting the 0 V to 2.4 V and 0 V to 2 V
analogue signal outputs to the data logger. Normally, the weather station is sited within 10 m of the
receiver, but, if necessary, these can be extended to optimise the weather station location.
Selecting an appropriate site for the weather station is critical in order to obtain data that is
representative of the LAS beam path. It must be sited away from the influence of obstructions such as
buildings, trees and other objects which might disturb the measurements of wind speed, temperature
and net radiation. As a rule of thumb, the minimum distance from an obstruction of height his 10h.
The ground around the mast should be flat. As the anchoring of the mast is based on 3 securing pins
to hold the guy wires, the soil must be stable enough to hold the load in high winds or when the
ground is wet. If in doubt, use a concrete foundation.
There must be a good, firm place to drive in the lightning rod earth spike.
2.3 Power supply
The LAS MKII transmitter requires 12 VDC nominal (9.6 –15 VDC), 6 W maximum with heater off and
54 W maximum with heater on (typically 26 W).
The LAS MKII receiver requires 12 VDC nominal (9.6 –15 VDC), 5 W maximum with heater off and
51 W maximum with heater on (typically 23 W).
For more information, please read the LAS MkII scintillometer manual.
The meteorological sensors and data logger require 12 VDC nominal, 4 W maximum with heaters off
and 18 W maximum with heaters on.
Note The data logger power requirement will be higher if an optional communication modem is
fitted. Please refer to the data logger and/or modem manual.
Mains AC power must be available for AC to 12 VDC convertors, if solar panel / battery power supplies
are not used.

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2.4 Assembling the meteorological mast and sensors
2.4.1 The mast
Assemble the mast horizontally on the ground in accordance with the dimensions shown below.

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The safe clamping zone of each section is indicated by red stripes on each mast section, as
shown below.
1. The nominal mast height of 4 m is achieved when clamping the sections at their lower marks.
2. The guy wires are supplied pre-assembled to triangular collar. This must be slid over the upper
section of the mast, as shown above, before fitting any other items.
3. The base plate has a socket for the bottom of the lowest mast section.
2.4.2 The mounting arms and sensors
Assemble the mounting arms and sensors to the mast as in the image below.
1. The U-shaped mounting arm is fitted to the top of the mast.
The wind direction sensor (WD) is mounted on the lower (shorter) ‘leg’ of the arm.
The wind speed sensor (u) and lightning rod are mounted on the upper (longer) ‘leg’.
2. The 2-sided mounting arm is fitted to the middle section of the mast at about 2.7 m.
The upper temperature sensor (T+) is mounted on the longer side of the arm.
The NR Lite2 net radiometer (Q* or Rn)is mounted on the shorter side of the arm.
The bubble level and the anti-bird stick must be facing upwards.
The net radiometer must be pointing towards the equator to avoid shadows from the mast.
3. The 1-sided mounting arm is fitted to the lower section of the mast at a height of about 0.5 m.
The lower temperature sensor (T-) is mounted on the arm.
The sensor must be oriented vertically below the upper temperature sensor.

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When the temperature sensors are positioned too close to each other no reliable direction
for the temperature gradient can be measured, particularly during the day. The minimum
distance between the sensors is 1.7 m.
The lower temperature sensor should not be mounted more than 1m above the ground (or
the effective surface height, such as the mean level of grass or a crop around the mast).
4. Use cable ties to fix the sensor cables to the mast and mounting arms and lead the cables to
the lower end of the mast, where at a later stage the data logger enclosure will be mounted.
2.5 Installing the mast
Two persons are required to erect the mast. One person holds the mast in an upright position whilst
the second person determines the positions where the guy wire securing pins will be driven into the
ground.
1. The lower guy ends are 0.3 m longer than theoretically required in order to hold the mast
vertical on an uneven surface. Two guy wire ends have a plain thimble, while the third has a
turnbuckle (cable tensioning device) for adjustment after erection of the mast.
The 3 guy rope securing pins should be driven in at an angle about 20°outwards from
vertical, as shown below and in 2.4.1.
2. The securing pin for the guy wire with the turnbuckle should be driven in last. First set the
bottle screw to its maximum length. Locate the securing pin so that the mast leans slightly
away from it. Use the bottle screw and a spirit level to make the mast vertical.

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The 3 guy ropes should have moderate and equal tension, do not put a bending force on the
mast.
3. Fix down the base plate of the mast with 4 smaller securing pins.
4. Finally, drive in the lightning rod earth spike
Check the guy wire tension and the mast alignment frequently. If the ground is not firm
enough to keep the mast vertical in all weather conditions, use concrete for anchoring.
2.6 Mounting the data logger enclosure
Once the mast, with mounting arms and sensors, is erected and levelled the stainless steel data logger
enclosure can be fixed to the lower section of the mast, as shown in the next two drawings. Use the
two clamps already fitted to the back of the enclosure. Allow at least 0.1 m clearance below the
enclosure for the cables to enter.

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The installation should now be as in the drawings above.
Note Check that the net radiometer is horizontal using the bubble level on its upper surface.
2.7 The soil heat flux sensors
The last sensors to be installed are the soil heat flux plates. Place them on the same side of the mast
as the net radiation sensor (towards the equator) and at a spot that is not disturbed by footsteps. The
measurements should be representative of the general area covered.

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Do not position the plates directly beneath the net radiation sensor, as they may disturb the
measurements
Depending on the soil type and the presence of vegetation the plates should be buried at a depth of
about 30 mm for bare soil conditions or just beneath the surface of fully covered soil (a few mm). In
the latter case the amount of ‘missing’ flux is as small as possible. Both plates should be at the same
depth and laterally separated by 30 –100 mm.
Do not bury the plates too deeply. At depths of 100 mm they can underestimate the soil heat flux by
more than 50%. Ensure that the plates are not measuring in air gaps or cracks. They must be in full
contact with the soil. When using more than 1 plate, burry them at the same depth.
2.8 Sensor overview
Sensor
Height/depth
Arm
Orientation/Direction
Wind speed (u)
4.4 m
U-shaped
Long ‘leg’
Wind direction (WD)
4.2 m
U-shaped
Short ‘leg’
Upper air temperature (T1)
2.7 m
2-sided
Opposite to radiation sensor
Net radiation (Q* or Rn)
2.7 m
2-sided
Towards equator to avoid shadows
Lower air temperature (T2)
0.5 - 1.0 m
1-sided
Directly below upper temperature sensor
Soil heat flux plate 1 (G1or HFP1)
3 - 30 mm
In ground
Towards equator, not below net radiometer
Soil heat flux plate 2 (G2or HFP2)
3 - 30 mm
In ground
As flux plate 1, separated by 30-100 mm
Air pressure (P)
-
In logger
enclosure
Breathes through sintered vent in bottom of
data logger enclosure
Data logger enclosure
At least 0.1 m
On mast

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2.9 Connecting the sensors
Note that the air pressure sensor (P) is pre-installed inside the data logger enclosure.
All cables (signal and power) enter the data logger enclosure at the bottom through weatherproof cable
glands and connect to the over-voltage protection (OVP) module terminals as in the following table.
The over-voltage protection blocks have spring-loaded terminals. 'Logger Terminal' refers to pre-wired
screw terminals on plug-in connectors on the data logger.
(the following 4 tables are new and should replace the existing ones)
Digital input /output channels
Instrument
Wire / Function
OVP
Logger Terminal
Input
Wind Speed
Yellow
1
I/O
D1
Green
2
0V
Wind Direction
Yellow
3
I/O
D2
Green
4
0V

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Analogue input channels
Instrument
Wire / Function
OVP
Logger Terminal
Input
Pressure sensor
19
SRC
AIN1
Yellow
20
In+
Green
21
In-
22
AGND
Net Radiation
23
SRC
AIN2
Red (Thermopile +)
24
In+
Blue (Thermopile −)
25
In-
26
AGND
UCn2 from LAS MkII
33
SRC
AIN3
Red
34
In+
Yellow
35
In-
36
AGND
UDemod from LAS MkII
37
SRC
AIN4
Green
38
In+
Make link wire to pin 35
39
In-
40
AGND
White
47
SRC
AIN5
Upper Temperature (T1)
Brown
48
In+
Pt-100
Green
49
In-
Yellow
50
AGND
White
51
SRC
AIN6
Lower Temperature (T2)
Brown
52
In+
Pt-100
Green
53
In-
Yellow
54
AGND
Heat Flux Plate, HFP1
57
SRC
AIN7
White
58
In+
Green
59
In-
60
AGND
Heat Flux Plate, HFP 2
61
SRC
AIN8
White
62
In+
Green
63
In-

20
64
AGND
12 VDC Power Output Terminals
Instrument
Wire / Function
Terminal
Power
Wind Speed
Pink / Brown
13
0 V
Grey / White
14
+12 V
Wind Direction
Pink / Brown
15
0 V
Grey / White
16
+12 V
Pressure sensor
Blue
17
0 V
In COMBILOG Enclosure
Red
18
+12 V
12 VDC Power Input
Customer Cable
Wire
Terminal
Input
DC power cable suitable
Usually Yellow / Green
PE
PROTECTIVE
for continuous outdoor
EARTH
use and compliant with
Usually Red
56
12V Pos
national and site safety
requirements (to be
Usually Black
55
12V Neg
supplied locally).
High current lightning
Heavy-duty copper cable
Stud in
EXTERNAL
and surge conductor
or strip to ground spike
enclosure
GROUND
'PE' refers to a Protective Earth for AC mains electrical safety and grounding ESD/OVP charges.
Where the solar radiation equipment is mounted on a roof, the building power distribution 'Earth' at an AC
power outlet socket is suitable for electrical safety as a Protective Earth. It is not sufficient for lightning and ESD
discharge, which should have a separate conductor directly from lightning rods on the roof, down the outside of the
building, to a ground spike.
Ensure that all AC and/or DC power to the COMBILOG is turned off when making connections. This may require
removing a fuse, or connector, to the positive terminal if a battery is supplied.
Insert instrument and power cables through individual cable glands in the COMBILOG enclosure, but only tighten
the gland nuts by hand until the cables are firmly gripped, tools may cause damage.
12 VDC Battery Connections (if supplied)
This sealed lead-acid back-up battery (7Ah capacity) must be installed after the COMBILOG enclosure is
mounted. The battery sits in the bottom of the COMBILOG enclosure. Pre-wired cables with push-on
spade terminals connect to the battery terminals, with red (positive) to battery + and the black
(negative) to battery −. There is a load protection fuse installed in the red battery cable.
Check that everything is properly fixed to the mast and that the net radiation sensor is level.
Read the relevant sections of the COMBILOG data logger manual.
Note The COMBILOG data logger in the ET System is pre-configured by Kipp & Zonen and will
automatically start measuring once connected to a power supply.
Switch on the power to the data logger enclosure and verify that all the sensors are working properly.