Campbell LP02 Instruction Manual

INSTRUCTION MANUAL

LP02 Pyranometer

Copyright © 2006- 2014

Campbell Scientific, Inc.

Revision: 1/14

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Table of Contents

PDF viewers: These page numbers refer to the printed version of this document. Use the
PDF reader bookmarks tab for links to specific sections.

1. Introduction ................................................................. 1

2. Cautionary Statements ............................................... 1

3. Initial Inspection ......................................................... 1

3.1 Ships With ............................................................................................ 1

3.2 Calibration Certificate .......................................................................... 1

4. Quickstart .................................................................... 2

4.1 Siting Considerations ........................................................................... 2

4.2 Mounting .............................................................................................. 2

4.3 Use SCWin to Program Datalogger and Generate Wiring Diagram .... 5

5. Overview ...................................................................... 8

6. Specifications ............................................................. 8

7. Operation ................................................................... 10

7.1 Wiring ................................................................................................ 10

7.2 Programming ...................................................................................... 11

7.2.1 Input Range ................................................................................. 11

7.2.2 Multiplier .................................................................................... 12

7.2.3 Offset .......................................................................................... 12

7.2.4 Example Programs ...................................................................... 12

7.2.4.1 CR1000 Example Program ............................................... 13

7.2.4.2 CR10X Example Program ................................................ 14

7.2.5 Output Format Considerations .................................................... 15

8. Maintenance .............................................................. 16

9. Troubleshooting........................................................ 16

Appendix

CM245 Adjustable Angle Mounting Stand ............ A-1

A.

Figures

A.1 Installation ....................................................................................... A-1

4-1. CM225 Bracket Attached to a Crossarm .............................................. 2

4-2. CM225 Bracket Attached to a Mast ..................................................... 3

4-3. LP02 Mounting Hole ............................................................................ 3

i

Table of Contents

Tables

4-4. CM225 Bracket Mounting Holes ........................................................ 4

4-5. LP02 Pyranometer Attached to CM225 Solar Sensor Mounting

Stand ................................................................................................ 4

7-1. LP02 Schematic ................................................................................. 10

A-1. CM245 bracket with 2.125 in. U-bolts positioned to mount the

pyranometer horizontally on a crossarm ...................................... A-1

A-2. CM245 bracket with 1.5 in. U-bolts positioned to mount

pyranometer at a 40° angle on a vertical pipe .............................. A-2

7-1. Differential Connections to Campbell Scientific Dataloggers ........... 10

7-2. Single-Ended Connections to Campbell Scientific Dataloggers........ 11

7-3. Multipliers Required for Flux Density and Total Fluxes ................... 12

7-4. Wiring for Example Programs ........................................................... 13

ii

LP02 Pyranometer

1. Introduction

The LP02 is an ISO-second-class pyranometer that monitors solar radiation for
the full solar spectrum range. It produces a millivolt signal that can be
measured directly by a Campbell Scientific datalogger. The LP02 can provide
solar radiation measurements for many meteorological applications. This
pyranometer is manufactured by Hukseflux.

Before using the LP02, please study:

• Section 2, Cautionary Statements

• Section 3, Initial Inspection

• Section 4, Quick Start

2. Cautionary Statements

• Although the LP02 is rugged, it is also a highly precise scientific

instrument and should be handled as such.

• Care should be taken when opening the shipping package to not damage or

cut the cable jacket. If damage to the cable is suspected, consult with a
Campbell Scientific application engineer.

3. Initial Inspection

• Upon receipt of the LP02, inspect the packaging and contents for damage.

File damage claims with the shipping company.

• The model number and cable length are printed on a label at the

connection end of the cable. Check this information against the shipping
documents to ensure the correct product and cable length are received.

• See Section 3.1, Ships With, to ensure that all of your parts are included.

3.1 Ships With

(1) Bolt for mounting from original manufacturer
(2) Nuts for mounting from original manufacturer
(1) Calibration certificate (see Section 3.2, Calibration Certificate)
(2) Bolts for mounting from original manufacturer
(1) ResourceDVD

3.2 Calibration Certificate

Included with the sensor is a calibration certificate with the sensor calibration
constant and serial number. Cross check this serial number against the serial
number on your LP02 to ensure that the given calibration constant corresponds
to your sensor.

1

LP02 Pyranometer

4. Quickstart

4.1 Siting Considerations

4.2 Mounting

Please review Section 7, Operation, for wiring, CRBasic programming, and
Edlog programming.

The LP02 is usually installed horizontally, but can also be installed at any
angle including an inverted position. In all cases, it will measure the flux that
is incident on the surface that is parallel to the sensor surface.

Site the LP02 to allow easy access for maintenance while ideally avoiding any
obstructions above the plane of the sensing element. It is important to mount
the LP02 such that a shadow will not be cast on it at any time. If this is not
possible, try to choose a site where any obstruction over the azimuth range
between earliest sunrise and latest sunset has an elevation not exceeding 5°.
Diffuse solar radiation is less influenced by obstructions near the horizon. For
instance, an obstruction with an elevation of 5° over the whole azimuth range
of 360° decreases the downward diffuse solar radiation by only 0.8%.

Below shows the steps for using the CM225 mounting bracket kit to mount the
LP02 to a vertical pipe (1.0 to 2.1 in. OD), or to a CM202, CM203, CM204, or
CM206 crossarm. If the sensor needs to be mounted at an angle, the CM245
Adjustable Angle Mounting Stand can be used instead (see Appendix A,
CM245 Adjustable Angle Mounting Stand).

1. Attach the CM225 to a mast or crossarm (see FIGURE 4-1 and FIGURE

4-2).

FIGURE 4-1. CM225 Bracket Attached to a Crossarm

2

LP02 Pyranometer

Mounting Hole

FIGURE 4-2. CM225 Bracket Attached to a Mast

2. Place the LP02 in the center of the CM225 with the cable pointing to the

nearest magnetic pole, and align the sensor’s mounting holes with two of
the bracket’s mounting holes (see FIGURE 4-3 and FIGURE 4-4).

FIGURE 4-3. LP02 Mounting Hole

3

LP02 Pyranometer

Mounting
Hole

Mounting
Hole

Mounting
Hole

Bubble Level

(3) Leveling Screws

CM225 Solar
Sensor
Mounting Stand

(2) Mounting Screws

CM200 Series
Crossarm

LP02 Pyranometer

Cable Tie

FIGURE 4-4. CM225 Bracket Mounting Holes

3. Place the mounting screws in the mounting holes and slightly tighten

them. The leveling screws should lightly touch the mounting plate (see
FIGURE 4-5).

FIGURE 4-5. LP02 Pyranometer Attached to CM225 Solar Sensor

Mounting Stand

4. Starting with the leveling screw nearest the bubble level, turn the leveling

screws to bring the bubble of the bubble level within the ring (see
FIGURE 4-5).

4

LP02 Pyranometer

5. Tighten the mounting screws to secure the assembly in its final position.

6. Route the sensor cable to the instrument enclosure.

7. Use cable ties to secure the cable to CM225 bracket and to the vertical

pipe or crossarm and tripod/tower (see FIGURE 4-5).

4.3 Use SCWin to Program Datalogger and Generate Wiring
Diagram

The simplest method for programming the datalogger to measure the LP02 is to
use Campbell Scientific’s SCWin Program Generator.

1. Open Short Cut and click on New Program.

2. Select the Datalogger Model and enter the Scan Interval.

5

LP02 Pyranometer

3. Select LP02 Pyranometer, and select the right arrow (in center of

screen) to add it to the list of sensors to be measured, and then select Next.

4. Enter the Sensitivity supplied on the manufacturer’s certificate of

calibration; this sensitivity is unique to each sensor. The public variables
defaults can typically be used. After entering the information, click on
OK, and then select Next.

6

5. Choose the Outputs and then select Finish.

LP02 Pyranometer

6. In the Save As window, enter an appropriate file name and select Save.

7. In the Confirm window, click Yes to download the program to the

datalogger.

8. Click on Wiring Diagram and wire according to the wiring diagram

generated by Short Cut.

7

LP02 Pyranometer

5. Overview

The LP02 pyranometer is designed for continuous outdoor use. Due to its flat
spectral sensitivity from 280 to 3000 nm, it can be used in natural sunlight,
under plant canopies, in green houses or buildings, and inverted to measure
reflected solar radiation. Two LP02s can be used in combination to measure
albedo. The LP02 can also be used to measure most types of artificial light
(Xenon lamps, Halogen lamps, etc.).

The LP02 pyranometer consists of a thermopile sensor, housing, dome, and
cable. The thermopile is coated with a black absorbent coating. The paint
absorbs the radiation and converts it to heat. The resultant temperature
difference is converted to a voltage by the copper-constantan thermopile. The
thermopile is encapsulated in the housing in such a way that it has a field of
view of 180 degrees and the angular characteristics needed to fulfill the cosine
response requirements.

The LP02’s cable has a user-specified length that can terminate in:

• Pigtails that connect directly to a Campbell Scientific datalogger

(cable termination option –PT).

6. Specifications

Features:

• Connector that attaches to a prewired enclosure (cable termination

option –PW).

• Connector that attaches to a CWS900 Wireless Sensor Interface (cable

termination option –CWS). The CWS900 enables the pyranometer to
be used in a wireless sensor network.

• Compatible with most Campbell Scientific dataloggers

• Measures reflected solar radiation when inverted

• Provides measurements in direct sunlight, under plant canopies, when

the sky is cloudy, and in artificial light

• Includes bubble level and leveling screws eliminating need for a

separate leveling base, which simplifies installation

• Compatible with the CWS900-series interfaces, allowing it to be used

in a wireless sensor network

• Acceptable for providing the solar radiation data used in stability

estimations

8

• Dome protects thermopile and allows water to roll off of it

Compatible Dataloggers: CR800

Overall classification according to ISO
Response time for 95% response:

18 s

Zero offset (response to 200 W m–2 net

Zero offset (response to 5 K/h change
Non-stability:

<1% change per year

Non-linearity:

<±1% (100 to 1000 W m–2)

Directional response for beam
Spectral selectivity:

±5% (280 to 3000 nm)

Temperature response
Tilt response:

within ±2%

Sensitivity (nominal):

15 μV(W m–2)

Expected voltage output:

0.1 to +50 mV in natural sunlight

Operating temperature range:

–40° to +80°C

Sensor resistance:

Between 40 and 60 Ω

Range:

0 to 2000 W m–2

Cable replacement:

Cable can be replaced by the user

Spectral range:

280 to 3000 nm (50% transmission

Leveling:

Level and leveling feet included

Expected accuracy for daily sums:

±10%

Dome diameter:

3 cm (1.2 in)

Height:

5.9 cm (2.3 in)

Body diameter:

7.8 cm (3.1 in)

Weight with 15 ft cable:

363 g (0.8 lb)

CR850
CR1000
CR3000
CR9000(X)
CR5000
CR23X
CR10(X)
CR510
CR500
21X
CR7

LP02 Pyranometer

9060 / WMO:

thermal radiation):

in ambient temperature):

radiation:

(within an interval of 50°C):

Second class pyranometer

<15 W m–2

<4 W m–2

within ±25 W m–2

±3% (–10° to +40°C)

points)

1

Guide to Meteorological Instruments and Methods of Observation, fifth

edition, WMO, Geneva and ISO9060

9

LP02 Pyranometer

White

Green

Clear

TABLE 7-1. Differential Connections to Campbell Scientific Dataloggers

7. Operation

7.1 Wiring

A schematic diagram of the LP02 is shown in FIGURE 7-1.

FIGURE 7-1. LP02 Schematic

When Short Cut is used to create the datalogger program, the sensor should be
wired to the channels shown in the wiring diagram created by Short Cut.

A differential voltage measurement is recommended because it has better noise
rejection than a single-ended measurement. If a differential channel is not
available, a single-ended measurement can be used.

Connections to Campbell Scientific dataloggers for a differential measurement
are given in TABLE 7-1. A user-supplied jumper wire should be connected
between the low side of the differential input and ground (AG or

) to keep

the signal in common mode range.

Connections to Campbell Scientific dataloggers for a single-ended
measurement are given in TABLE 7-2.

Color

Description

CR9000(X)
CR5000
CR3000
CR1000
CR800
CR850

CR510
CR500
CR10(X)

21X
CR7
CR23X

White Signal (+) DIFF Analog High DIFF Analog High DIFF Analog High

Green Signal (–) *DIFF Analog Low *DIFF Analog Low *DIFF Analog Low

Clear Shield

G

* Jumper to AG or

with user supplied wire.

10

LP02 Pyranometer

TABLE 7-2. Single-Ended Connections to Campbell Scientific Dataloggers

Color

Description

CR9000(X)
CR5000
CR3000
CR1000
CR800
CR850

CR510
CR500
CR10(X)

21X
CR7
CR23X

White Signal (+) Single-Ended Analog Single-Ended Analog Single-Ended Analog

Green Signal (–)

Clear Shield

AG

G

7.2 Programming

This section is for users who write their own datalogger programs. A
datalogger program to measure this sensor can be created using Short Cut.
You do not need to read this section to use Short Cut.

–2

Solar radiation can be reported as an average flux density (W m

–2

flux density (MJ m

). The appropriate multipliers are listed in TABLE 7-3.
Programming examples are given for both average and daily total solar
radiation.

The LP02 outputs a low level voltage ranging from 0 to a maximum of up to
35 mV, in natural light, depending on the calibration factor and radiation level.

) or daily total

7.2.1 Input Range

A differential voltage measurement is recommended because it has better noise
rejection than a single-ended measurement. If a differential channel is not
available, a single-ended measurement can be used. The acceptability of a
single-ended measurement can be determined by simply comparing the results
of single-ended and differential measurements made under the same
conditions.

The output voltage of the LP02 is usually between 10 and 35 mV per

–2

1000 W m
maximum value of solar radiation of 1100 W m

. When estimating the maximum likely value of sensor output, a

–2

can be used for field

measurements on a horizontal surface.

Select the input range as follows:

1. Estimate the maximum expected input voltage by multiplying the

maximum expected irradiance (W m

–2

). Divide the answer by 1000 to give the maximum in millivolt

W m

–2

) by the calibration factor (µV/

units.

2. Select the smallest input range which is greater than the maximum

expected input voltage. Normally the 50 mV range for the CR3000,
CR9000(X), CR5000, CR7, CR23X, 21X, and the 25 mV or 250 mV
range for the CR800, CR850, CR1000, CR10X, CR510, and CR500 will
be suitable. The exact range will depend on the sensitivity of your

11

LP02 Pyranometer

TABLE 7-3. Multipliers Required for Flux Density and Total Fluxes

7.2.2 Multiplier

individual sensor and the maximum expected reading. With some
dataloggers, an autorange option can be used if measurement time is not
critical.

The parameter code for the input range also specifies the measurement
integration time. The slow or 60 Hz rejection integration gives a more noise­free reading. A fast integration takes less power and allows for faster
throughput.

The multiplier converts the millivolt reading to engineering units. The
calibration supplied by the manufacturer gives the output of the sensor (c) as

–6

microvolts (V x 10

)

per W m–2. As the datalogger voltage measurement

instructions give a default output in mV, the following equation should be used

–2

to calculate the multiplier (m) to give the readings in W m

:

m = 1000/c

Other units can be used by adjusting the multiplier as shown in TABLE 7-3.

Units Multipliers Output Processing

W m–2 m Average

MJ m–2 M•t•0.000001 Total

kJm–2

cal cm–2 M•t•0.0239*0.001 Total

cal cm–2 min–1 M•1.434•0.001 Average

m = calibration factor in W m-2/mV
t = datalogger program execution interval in seconds

7.2.3 Offset

The offset will normally be fixed at zero as the sensor should output no
significant signal in dark conditions. In practice, because of the nature of
thermopile detector sensors, there will be some offset in dark conditions;
sometimes this offset can give negative light readings. This offset varies with
several factors (for example, rate of change of sensor temperature), so it cannot
be removed with a fixed offset. Some users may wish to remove small
negative readings by including code after the measurement instructions that
sets negative readings to zero.

7.2.4 Example Programs

M•

t•0.001

Total

The following programs measure the LP02 every 10 seconds and convert the

–2

mV output to W m

and MJ m–2. A sensor calibration of 15.02 µV per W m–2

is used for the example programs. Both programs output an hourly average

–2

flux (W m

), and a daily total flux density (MJ m–2).

12

LP02 Pyranometer

TABLE 7-4. Wiring for Example Programs

Wiring for the examples is given in TABLE 7-4.

Color Description CR1000 CR10X

White Signal (+) DIFF Analog High DIFF Analog High

Green Signal (–) *DIFF Analog Low *DIFF Analog Low

Clear Shield

G

* Jumper to AG or

with user supplied wire.

7.2.4.1 CR1000 Example Program

'CR1000

'Declare Variables and Units

Public Solar_Wm2
Public Solar_MJ

Units Solar_Wm2=W/m²
Units Solar_MJ=MJ/m²

'Hourly Data Table

DataTable(Table1,True,-1)
DataInterval(0,60,Min,10)
Average(1,Solar_Wm2,FP2,False)
EndTable

'Daily Data Table

DataTable(Table2,True,-1)
DataInterval(0,1440,Min,10)
Totalize(1,Solar_MJ,IEEE4,False)
EndTable

'Main Program

BeginProg
Scan(10,Sec,1,0)

'LP02 Pyranometer measurement in Wm-2:

'The Multiplier (m) for this example is based upon a sensor calibration (c) of
'15.02 µV/Wm-2, and will be different for each sensor.
'Multiplier (m) = 1000/c = 66.577896.

VoltDiff(Solar_Wm2,1,mV25,1,True,0,_60Hz,66.577896,0) ‘use the 50 mV range for the
CR3000, CR5000 and CR9000
'Set negative readings to zero:

If Solar_Wm2<0 Then Solar_Wm2=0

'Calculate units in MJ, where MJ = m * t * 0.000001. m = Solar_Wm2 from above, and
't = 10 (scan interval)

Solar_MJ=Solar_Wm2*0.00001

13

LP02 Pyranometer

'Call Data Tables and Store Data

CallTable(Table1)
CallTable(Table2)
NextScan
EndProg

7.2.4.2 CR10X Example Program

;{CR10X}

*Table 1 Program
01: 10.0000 Execution Interval (seconds)

; LP02 measurement in Wm-2

1: Volt (Diff) (P2)
1: 1 Reps
2: 23 25 mV 60 Hz Rejection Range ;use the 50 mV range for the CR7, 21X and CR23X
3: 1 DIFF Channel ;use the 250 mV range for the CR10X if
4: 3 Loc [ Solar_Wm2 ] calibration factor is > 25 µV/Wm-2
5: 66.5778 Multiplier
6: 0 Offset

; Set negative values to zero

2: If (X<=>F) (P89)
1: 3 X Loc [ Solar_Wm2 ]
2: 4 <
3: 0 F
4: 30 Then Do

3: Z=F x 10^n (P30)
1: 0 F
2: 0 n, Exponent of 10
3: 3 Z Loc [ Solar_Wm2 ]

4: End (P95)

; Calculate units in MJ, where MJ = m * t * 0.000001.
; m = Solar_Wm2 from above, and t = 10 (scan interval).

5: Z=X*F (P37)
1: 3 X Loc [ Solar_Wm2 ]
2: .00001 F
3: 4 Z Loc [ Solar_MJ ]

6: If time is (P92)
1: 0 Minutes (Seconds --) into a
2: 60 Interval (same units as above)
3: 10 Set Output Flag High (Flag 0)

7: Set Active Storage Area (P80)
1: 1 Final Storage Area 1
2: 101 Array ID

8: Real Time (P77)
1: 1220 Year,Day,Hour/Minute (midnight = 2400)

14

9: Average (P71)
1: 1 Reps
2: 3 Loc [ Solar_Wm2 ]

10: If time is (P92)
1: 0 Minutes (Seconds --) into a
2: 1440 Interval (same units as above)
3: 10 Set Output Flag High (Flag 0)

11: Set Active Storage Area (P80)
1: 1 Final Storage Area 1
2: 102 Array ID

12: Real Time (P77)
1: 1220 Year,Day,Hour/Minute (midnight = 2400)

13: Resolution (P78)
1: 1 High Resolution

14: Totalize (P72)
1: 1 Reps
2: 4 Loc [ Solar_MJ ]

15: Resolution (P78)
1: 0 Low Resolution

LP02 Pyranometer

7.2.5 Output Format Considerations

In CRBasic, store the data in the IEEE4 format if the measurements will be
totalized.

When using Edlog, the largest number the datalogger can store in Final Storage
is 6999 in low resolution mode (FP2) and 99999 in high resolution mode (if
available). If the measurement value is totalized, there is some danger of over­ranging the output limits, as shown in the following example:

Example

Assume that daily total flux is desired, and that the datalogger scan rate is 1
second. With a multiplier that converts the readings to units of kJm
average irradiance of 0.5k W m
will be exceeded in less than four hours.

The following solutions can be used to prevent overranging:

Solution 1 – Change the multiplier in the instruction to (m•0.0001). This will
totalize MJ m

Solution 2 – Record the average flux density and later multiply the result by the
number of seconds in the output interval to arrive at total flux.

Solution 3 – Record the total flux using the high resolution format. The
drawback to high resolution is that it requires four bytes of memory per data
point, consuming twice as much memory as low resolution. Instruction 78 is
used to switch to high resolution in the Edlog dataloggers.

–2

instead of kJm–2.

–2

–2

, the maximum low resolution output limit

and an

15

LP02 Pyranometer

8. Maintenance

Inspect and clean the outer dome at regular intervals, for example, every week
or so. Clean any accumulated dust, etc. off the dome and pyranometer body
using a soft cloth dampened with water or alcohol. Check that there is no
condensation within the dome.

It is also important to check the data returned from the sensor as it will show
the first indication of a fault. Be aware of several expected phenomena that can
cause strange measurements. In particular, on clear, windless nights the outer
dome temperature of horizontally placed pyranometers can fall as low as the
dewpoint temperature of the air, due to infrared radiation exchange with the
cold sky. (The effective sky temperature can be 30°C lower than the ground
temperature, which results in an infrared emission of –150 W m
happens, dew, glazed frost or hoar frost can be precipitated on the top of the
outer dome and can stay there for several hours in the morning. An ice cap on
the dome is a strong diffuser and can decrease the pyranometer signal by up to
50% in the first hours after sunrise.

The calibration of the LP02 may drift with time and exposure to radiation.
Recalibration every two years is recommended. The sensor should be returned
to Campbell Scientific, the manufacturer, or a calibration lab with facilities to
calibrate radiation sensors.

–2

). If this

9. Troubleshooting

Symptom: NAN, –9999, or radiation values around 0

1. Check that the sensor is wired to the differential channel specified by the
measurement instruction.

2. Verify that the range code is correct for the datalogger type.

3. Measure the impedance across the sensor wires. This should be around
100 Ω plus the cable resistance (typically 0.1 Ω m
very low, there may be a short circuit (check the wiring). Resistances
somewhat lower than expected could be due to water ingress into the
sensor or enclosure connectors. If the resistance is infinite, there is a
broken connection (check the wiring).

4. Disconnect the sensor cable and check the voltage between pins 1 and 3
on the sensor. With the sensor located 8 inches below a 60 W
incandescent light bulb the voltage should be approximately 2.5 mV. No
voltage indicates a problem with the sensor.

Symptom: sensor signal is unrealistically high or low

1. Check that the right calibration factor has been properly entered into the
datalogger program. Please note that each sensor has its own individual
calibration factor.

–1

). If the resistance is

2. Check the condition of the sensor cable.

16

LP02 Pyranometer

Symptom: sensor signal shows unexpected variations

1. Check for the presence of strong sources of electromagnetic radiation
(radar, radio etc.)

2. Check the condition and the connection of the sensor shield wire.

3. Check the condition of the sensor cable.

17

LP02 Pyranometer

18

First

2.125
U

Second

2.125 in
U

Second

2.125 in
U

First

2.125 in
U

90

Pyranometer
mounts here

Appendix A. CM245 Adjustable Angle
Mounting Stand

A.1 Installation

The CM245 includes slots that allow it to be adjusted to any angle from
horizontal to vertical. If mounting the pyranometer at an angle, ensure that the
crossarm is leveled horizontally before placing the bracket at its proper angle.
Angle positions are included on the bracket label (see FIGURE A-1 and
FIGURE A-2).

in

-bolt

-bolt

FIGURE A-1. CM245 bracket with 2.125 in. U-bolts positioned to mount

the pyranometer horizontally on a crossarm

-bolt

-bolt

A-1

Appendix A. CM245 Adjustable Angle Mounting Stand

First

1.5 in
U

Second

1.5 in
U

40

pn 17446

pn 4365

pn 4366

pn 27291

pn 17446

1.50 in

-bolt

-bolt

FIGURE A-2. CM245 bracket with 1.5 in. U-bolts positioned to mount

pyranometer at a 40° angle on a vertical pipe

Do the following to level the pyranometer horizontally:

1. Attach the mounting stand to the crossarm.

2. Loosely mount the pyranometer on the mounting stand. Do not fully

tighten the two mounting screws.

3. Turn the leveling screws as required to bring the bubble of the level within

the ring.

4. Tighten the mounting screws to secure the assembly in its final position.

Check that the pyranometer is still correctly leveled and adjust as necessary.

A-2

Campbell Scientific Companies

Campbell Scientific, Inc. (CSI)

815 West 1800 North

Logan, Utah 84321

UNITED STATES

www.campbellsci.com • [e-mail]

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PO Box 2450

Somerset West 7129

SOUTH AFRICA

www.csafrica.co.za • [e-mail]

Campbell Scientific Australia Pty. Ltd. (CSA)

PO Box 8108

Garbutt Post Shop QLD 4814

AUSTRALIA

www.campbellsci.com.au • [e-mail]

Campbell Scientific do Brasil Ltda. (CSB)

Rua Apinagés, nbr. 2018 ─ Perdizes

CEP: 01258-00 ─ São Paulo ─ SP

BRASIL

www.campbellsci.com.br • [e-mail]

Campbell Scientific Canada Corp. (CSC)

14532 – 131 Avenue NW

Edmonton AB T5L 4X4

CANADA

www.campbellsci.ca • [e-mail]

Campbell Scientific Centro Caribe S.A. (CSCC)

300 N Cementerio, Edificio Breller

Santo Domingo, Heredia 40305

COSTA RICA

www.campbellsci.cc • [e-mail]

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Campbell Park

80 Hathern Road

Shepshed, Loughborough LE12 9GX

UNITED KINGDOM

www.campbellsci.co.uk • [e-mail]

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3 Avenue de la Division Leclerc

92160 ANTONY

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Fahrenheitstraße 13

28359 Bremen

GERMANY

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Avda. Pompeu Fabra 7-9, local 1

08024 Barcelona

SPAIN

www.campbellsci.es • [e-mail]

Please visit www.campbellsci.com to obtain contact information for your local US or international representative.