LI-COR LI-200R User manual

LI-200R
Pyranometer
Instruction Manual

LI-200R Pyranometer
Instruction Manual
Publication Number 984-15210
LI-COR®, Inc.
4647 Superior Street
Lincoln, Nebraska 68504 USA
Telephone: [phone]
FAX: [phone]
Toll Free: 1-800-447-3576 (U.S. & Canada)
[e-mail]
www.licor.com/env/support/
www.licor.com

NOTICE
The information contained in this document is subject to change without notice.
LI-COR® MAKES NO WARRANTY OF ANY KIND WITH REGARD TO THIS
MATERIAL, INCLUDING, BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. LI-COR 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.
This document contains proprietary information which is protected by copyright. All rights
are reserved. No part of this document may be may be reproduced or translated into another
language with prior written consent of LI-COR, Inc.
All other trademarks or registered trademarks are property of their respective owners.
© Copyright 2015, LI-COR, Inc.
LI-COR, Inc.
4647 Superior Street
Lincoln, NE 68504
Phone: [phone]
Toll Free (U.S. and Canada): 1-800-447-3576
In Germany - LI-COR GmbH: [phone]
www.licor.com/env
[e-mail]
This product is a CE-marked product. For conformity information, contact
LI-COR Support at [e-mail]. Outside of the U.S., contact your
local sales office or distributor.
This device complies with part 15 of the FCC Rules. Operation is subject to the
following two conditions: (1) This device may not cause harmful interference,
and (2) this device must accept any interference received, including interference
that may cause undesired operation.
ii

iii
Printing History
Publication Number: 984-15210
New editions of this manual will include all updates. An update addendum may be used
between editions to provide up-to-date information. Revisions are indicated by the revision
number. Minor updates, which do not alter the meaning of the content, will be incorporated
without affecting the revision number.
Version
Number
Publication Date Changes
1 April 2015 First Edition
2 May 2015 Second Edition; Edited Troubleshooting section.
3 July 2015 Added specifications for operating temperature and relative
humidity range; Updated sensitivity specification.
4 November 2015 Removed specification for relative humidity range.
Corrected wire positioning in the photo that shows how to
connect a sensor to the 2420-BL Light Sensor Amplifier.
Build Date: Monday, November 02, 2015

Lead (Pb) Mercury (Hg) Cadmium (Cd)
Chromium VI
Compounds
(Cr6+)
Polybrominated
Biphenyls
(PBB)
Polybrominated
Diphenyl Ethers
(PBDE)
(Pb) (Hg) (Cd) (Cr6+) (PBB) (PBDE)
X O O O O O
X: this component does contain this hazardous substance above the maximum concentration values in homogeneous materials
specified in the SJ/T 11363-2006 Industry Standard (Company can explain the technical reasons for the "X")
Hazardous Substances or Elements
Component Name
O: this component does not contain this hazardous substance above the maximum concentration values in homogeneous
materials specified in the SJ/T 11363-2006 Industry Standard.
,(6002-36311T/JS:X
)"X"
6002-36311T/JS:O o
Doc. #53-14982 March 23, 2015
LI-200R-BL-x; LI-200R-BNC-x (x = 2, 5, 15, 50)
LI-200R-BL-x; LI-200R-BNC-x (x = 2, 5, 15, 50)
Pyranometer Sensor Head Assembly
Base and Cable Assembly
X O O O O O
X O O O O O
X O O O O O
强
Lead (Pb) Mercury (Hg) Cadmium (Cd)
Chromium VI
Compounds
(Cr6+)
Polybrominated
Biphenyls
(PBB)
Polybrominated
Diphenyl Ethers
(PBDE)
(Pb) (Hg) (Cd) (Cr6+) (PBB) (PBDE)
X O O O O O
X O O O O O
X O O O O O
X: this component does contain this hazardous substance above the maximum concentration values in homogeneous materials
specified in the SJ/T 11363-2006 Industry Standard (Company can explain the technical reasons for the "X")
Hazardous Substances or Elements
Component Name
O: this component does not contain this hazardous substance above the maximum concentration values in homogeneous
materials specified in the SJ/T 11363-2006 Industry Standard.
,(6002-36311T/JS:X
)"X"
6002-36311T/JS:O
Doc. #53-15083 March 23, 2015
LI-200R-SMV-x (x = 2, 5, 15, 50)
LI-200R-SMV-x (x = 2, 5, 15, 50)
Pyranometer Sensor Head Assembly
Millivolt Adapter Assembly
Base and Cable Assembly
X O O O O O
X O O O O O
X O O O O O
iv

v
Lead (Pb) Mercury (Hg) Cadmium (Cd)
Chromium VI
Compounds
(Cr6+)
Polybrominated
Biphenyls
(PBB)
Polybrominated
Diphenyl Ethers
(PBDE)
(Pb) (Hg) (Cd) (Cr6+) (PBB) (PBDE)
X O O O O O
X: this component does contain this hazardous substance above the maximum concentration values in homogeneous materials
specified in the SJ/T 11363-2006 Industry Standard (Company can explain the technical reasons for the "X")
Hazardous Substances or Elements
Component Name
O: this component does not contain this hazardous substance above the maximum concentration values in homogeneous
materials specified in the SJ/T 11363-2006 Industry Standard.
,(6002-36311T/JS:X
"X" o
6002-36311T/JS:O o
Doc. #53-14832 March 23, 2015
2420-BL
2420-BL
Amplifier Bare Lead Assembly X O O O O O
Lead (Pb) Mercury (Hg) Cadmium (Cd)
Chromium VI
Compounds
(Cr6+)
Polybrominated
Biphenyls
(PBB)
Polybrominated
Diphenyl Ethers
(PBDE)
(Pb) (Hg) (Cd) (Cr6+) (PBB) (PBDE)
X O O O O O
X: this component does contain this hazardous substance above the maximum concentration values in homogeneous materials
specified in the SJ/T 11363-2006 Industry Standard (Company can explain the technical reasons for the "X")
Hazardous Substances or Elements
Component Name
O: this component does not contain this hazardous substance above the maximum concentration values in homogeneous
materials specified in the SJ/T 11363-2006 Industry Standard.
,(6002-36311T/JS:X
"X" o
6002-36311T/JS:O o
Doc. #53-14833 March 23, 2015
2420-BNC
2420-BNC
Amplifier BNC Assembly X O O O O O

vi

vii
Table of Contents
Section 1. General Information
Comparing LI-COR® Radiation Sensors 1-1
Cable Options 1-2
Accessories 1-3
Configurations 1-4
Section 2. Using the LI-200R Pyranometer
Mounting 2-1
Calibration Constants and Multipliers 2-2
Using the LI-200R-BNC Pyranometer 2-3
Using the LI-200R-BL Pyranometer 2-3
Voltage Signal Options 2-4
Section 3. Millivolt Adapters
2220 Millivolt Adapter 3-1
Connecting the 2220 Millivolt Adapter 3-2
LI-200R-SMV Pyranometer 3-3
Connecting the LI-200R-SMV Pyranometer 3-3
Section 4. 2420 Light Sensor Amplifier
2420 Amplifier Gain Settings 4-1
Connecting to a Data Logger 4-4
Connecting to a Sensor 4-6
Equation Summary 4-7
Output Voltage 4-7
Ideal Gain 4-7
Voltage Multiplier 4-7
2420 Amplifier Performance Characteristics 4-8
Output 4-8
2420 Amplifier Specifications 4-8
Section 5. Performance Characteristics

Cosine Response 5-1
LI-200R Cosine Correction 5-1
Spectral Response 5-3
Calibration 5-5
Section 6. Care and Maintenance
Factory Recalibration 6-2
Removing a Cable 6-2
Sensor Base Cover 6-3
Installing a Cable 6-3
Replacement Parts 6-4
Section 7. Troubleshooting
Appendix A. Specifications
LI-200R Pyranometer Specifications A-1
Appendix B. Warranty
Appendix C. Index
viii

Section 1.
General Information
This manual provides basic operating instructions for the
LI-200R Pyranometer and its accessories. The LI-200R
measures global solar radiation (solar irradiance received
on a horizontal surface) with a silicon photodiode
mounted under a cosine-corrected acrylic diffuser. The
sensor output is a current (μA) signal that is directly
proportional to hemispherical solar radiation. A multiplier is used to convert the
current signal into units of radiation (W m-2).
Typical applications for the LI-200R include solar energy, meteorology,
agriculture, and environmental research.
Important Note: The LI-200R should only be used to measure unobstructed
daylight. Measurements under vegetation, cloud cover, artificial lights, in a
greenhouse, or of reflected solar radiation may not be accurate. The spectral
response of the LI-200R does not include the entire solar spectrum (Figure
5-3). Therefore, it must be used under lighting conditions that are the same
as those under which it was calibrated.
Comparing LI-COR® Radiation Sensors
Each LI-COR radiation sensor is optimized for a particular application and
measurement type (Table 1-1). LI-192SA and LI-193SA sensors are submersible,
but they can also be used in the atmosphere. The LI-191R Line Quantum
Sensor is often used within plant canopies. LI-190R, LI-200R, and LI-210R
sensors consist of a sensor head attached to a removable base and cable
assembly.
1-1

Sensor Measurement Units Waveband
LI-190R Quantum Sensor
Photosynthetically
active radiation (PAR) μmol s-1 m-2 400 to 700 nm
LI-191R Line Quantum Sensor
LI-192SA Underwater Quantum
Sensor
LI-193SA Underwater Spherical
Quantum Sensor
LI-200R Pyranometer Global solar radiation W m-2 400 to 1100 nm
LI-210R Photometric Sensor Light as perceived by
the human eye
Lux or klux 450 to 650 nm
Table 1-1. LI-COR radiation sensors.
Figure 1-1. LI-COR radiation sensors.
Cable Options
The detachable base and cable assembly provides benefits including:
•Reduced cost of cable repairs
•The ability to replace or recalibrate a light sensor without removing the
cable from the mounting structure
•Cable interchangeability with any LI-190R, LI-200R, or LI-210R sensor head
1-2
Section 1. General Information

Figure 1-2. Sensor base and cable assembly detached from the sensor head.
The shielded cable leading from the sensor base terminates with either bare
wire leads or a weather-resistant, nickel-plated brass BNC connector (Figure
1-3). For sensors with a BNC connector, the body of the connector carries a
positive signal and is connected to the shield of the cable, while the center
conductor is negative. This arrangement reduces electronic interference.
Figure 1-3. Sensor Terminal Types.
BNC or bare leads (BL) terminal types are available with cable lengths of 2, 5,
15, or 50 meters.
Calibrated LI-190R, LI-200R, or LI-210R sensor heads
(without cables) are available for purchase from LI-COR.
Sensor heads can replace damaged heads, or be used as
spares.
Any base and cable assembly can be used interchangeably
with any LI-190R, LI-200R, or LI-210R sensor head.
Accessories
These optional accessories are available for use with the LI-200R Pyranometer:
•2220 Millivolt Adapter, 147 Ω resistance (see page 3-1)
•2420 Light Sensor Amplifier (see page 4-1)
•2003S Mounting and Leveling Fixture. Anodized aluminum with stainless
steel leveling screws and a weatherproof spirit level
•2001S Sensor Base Cover. Anodized aluminum
1-3
Section 1. General Information

Configurations
The LI-200R Pyranometer connects directly to devices that read a current (µA)
sensor signal (Table 1-2). Table 1-3 lists pyranometer configurations for
producing a voltage signal.
Sensor Termination Type Connects to...
LI-200R-BNC lLI-1500 Light Sensor Logger
lLI-1400 Datalogger
lLI-250A Light Meter
LI-200R-BL lTerminal block of the LI-1400 Datalogger
lNon-LI-COR devices that read a current (μA) signal
Table 1-2. Configurations for a current (µA) signal. Ultimate termination is BNC or bare leads.
Sensor Termination Type Coupled with... Connects to...
LI-200R-BNC 2220 mV Adapter
(0 to 10 mV output) Devices that read a voltage
signal with good resolution (in
the µV range)
LI-200R-SMV Includes a standard output mV adapter
with 10 mV output at full scale (part number 2320)
LI-200R-BL Precision resistor
LI-200R-BNC 2420-BNC Amplifier
(-2.5 to 5.0 V output) Devices that read a voltage
signal
LI-200R-BL 2420-BL Amplifier
(-2.5 to 5.0 V output)
Table 1-3. Configurations for a voltage signal. Ultimate termination is bare leads.
1-4
Section 1. General Information

Section 2.
Using the LI-200R
Pyranometer
Mounting
The LI-200R Pyranometer may be hand-held or mounted to an instrument
platform. For best results, install your sensor in the 2003S Mounting and
Leveling Fixture. Secure the sensor in the fixture by tightening the mounting
screws against the sensor base. Level the fixture with the bubble by adjusting
the three leveling screws. The 2003S Mounting and Leveling Fixture can be
secured to a structure with bolts or screws placed through the three holes in the
fixture.
Figure 2-1. LI-200R Pyranometer mounted in the 2003S Mounting and Leveling Fixture.
2-1

Secure cables to the instrument platform using cable ties. Be sure there is no
strain on the junction where the cable enters the sensor housing, and use a
cable tie at any sharp bends in the cable.
Calibration Constants and Multipliers
Each LI-COR radiation sensor is shipped with a certificate of calibration. The
certificate is also available at www.licor.com/env/support/. Enter the
sensor's serial number in the calibration search box. The calibration constant
and multipliers are listed on the certificate in the following order:
1. Calibration constant. The current signal produced by a sensor is related to
radiation intensity with a calibration constant unique to each pyranometer,
expressed in units of µA per 1000 W m-2. The calibration constant is used to
compute calibration multipliers.
2. Multiplier for use with LI-COR handheld meters and loggers. LI-COR
handheld meters and loggers convert the current (μA) signal into units of
radiation (W m-2) by applying this multiplier, expressed in radiation units per
current (W m-2 µA-1). This multiplier is a negative number.
3. Multiplier for use with LI-200R-BL (3-wire bare leads). This multiplier is
expressed in radiation units per current (W m-2 µA-1) and is a positive number.
4. Multiplier for use with LI-COR 2220 (147Ω) Milllivolt Adapter. This
multiplier is expressed in radiation units per voltage (W m-2 mV-1) and is a
negative number.
5. Multiplier for use with the SMV Pyranometer. The final multiplier listed is
-100.0 W m-2 mV-1. The multiplier is the same for any LI-200R-SMV
Pyranometer because the resistance of the included standard output millivolt
adapter (part number 2320) is adjusted to each sensor's current output (see page
3-3). The LI-200R-SMV replaces the LI-200SL and uses the same millivolt
adapter and multiplier.
2-2
Section 2. Using the LI-200R Pyranometer

Using the LI-200R-BNC Pyranometer
Figure 2-2. LI-200R-BNC Pyranometer.
Connect the BNC-type cable directly to a BNC input
port on an LI-250A Light Meter, LI-1400 Datalogger, or
LI-1500 Light Sensor Logger. These devices directly
measure the current (μA) signal from the sensor. Enter
the sensor's multiplier (see "Multiplier for use with LI-
COR handheld meters and loggers" on the previous
page) into the device to determine global solar radiation
expressed in units of W m-2.
Using the LI-200R-BL Pyranometer
Figure 2-3. LI-200R-BL Pyranometer featuring 3-wire bare leads.
A BL-type sensor cable terminates with bare wire leads. Connect the bare leads
to the input terminal block of a device that directly measures a current (μA)
signal. The blue wire carries a positive signal and the brown wire is negative.
Connecting the bare (shield) wire to ground will reduce noise in the sensor
signal.
2-3
Section 2. Using the LI-200R Pyranometer

Blue: Positive Signal (+)
Brown: Negative Signal (-)
Bare: Shield (Ground)
To log radiation units (W m-2), configure the recording device to multiply the
μA signal by the sensor's multiplier (see "Multiplier for use with the LI-200R-
BL" on page 2-2) prior to logging the values. If logging the μA sensor signal,
apply the multiplier after logging.
The LI-200R-BL can be used with recording devices that require a voltage (mV)
signal by adding a precision resistor (see "Voltage Signal Options" below).
Voltage Signal Options
If the meter or logging device requires a voltage signal, options include:
•LI-200R-BNC coupled with a 2220 Millivolt Adapter. The 2220 Millivolt
Adapter converts the current (µA) signal from the sensor into a millivolt-
level voltage (see page 3-1).
•LI-200R-SMV Pyranometer. The LI-200R-SMV includes a Standardized
Millivolt Adapter (part number 2320) matched to a particular sensor. The
serial numbers on the adapter and the sensor must match! The advantage
over the 2220 Millivolt Adapter is that the multiplier in your device does not
need to be changed for different sensors (see page 3-3).
•LI-200R coupled with a 2420 Light Sensor Amplifier. The 2420 Amplifier
converts the current (µA) signal from the sensor into a voltage (see page 4-
1).
•LI-200R-BL coupled with a precision resistor. Connect the resistor across
the positive and negative leads of the cable. The recommended resistance is
147 Ω, with a maximum output of approximately 10 mV per 1000 W m-2.
See"2220 Millivolt Adapter" on page 3-1 for instructions on calculating the
multiplier, but use the absolute value of the multiplier.
With a Millivolt Adapter or other resistor, the signal to noise ratio (sensitivity) is
lower than with the 2420 Light Sensor Amplifier, but the cost is less and there
is no need for a power supply to the adapter.
Caution: Do not attach the sensor to a power source. The sensor is self-
powered.
2-4
Section 2. Using the LI-200R Pyranometer

Section 3.
Millivolt Adapters
LI-COR radiation sensors produce a current (μA) output signal that can be
converted to a voltage through the use of a resistor. LI-COR makes two types of
millivolt adapters for use with our BNC-type radiation sensors. Each adapater
includes a precision resistor and a BNC connector that mates with the sensor.
Bare leads can be connected to a data logger or other device that reads a voltage
signal.
The maximum output of LI-COR radiation sensors in typical conditions is
relatively small (microamps of current) and converts into a small voltage. To
monitor these sensors with expected accuracy, a data logger needs to have the
ability to measure in the microvolt range. To increase sensitivity, make sure the
voltage range of the channel is set as close as possible to the full-scale range of
the sensor. For example, 0 to 25 mV should cover the range of values expected
in a natural sunlight environment.
If the data logger does not have the ability to measure microvolt signals or the
ability to set channel voltage ranges down to a 0–25 mV level, another option
should be considered, such as the 2420 Light Sensor Amplifier.
2220 Millivolt Adapter
3-1

An LI-200R Pyranometer with a BNC-type cable can be used with a millivolt
recorder or data logger by connecting a model 2220 Millivolt Adapter. Convert
the voltage measured by the data logger into radiation units (W m-2) by
applying the appropriate multiplier, given on the sensor's certificate of
calibration (see "Multiplier for use with LI-COR 2220" on page 2-2).
The multiplier Mfor use with a millivolt adapter can also be found by:
M=G C
1−
⋅
The 2220 Millivolt Adapter includes a precision resistor with a fixed resistance
of 147 Ω, tolerance of ± 0.1%, and a fixed gain of G= 0.147 mV μA-1. The
sensor's calibration constant Cis found on the certificate of calibration (see
"Calibration constant" on page 2-2). The calculated multiplier will be a negative
number (because the shield of the coaxial cable of the sensor carries the positive
signal) and is expressed in units of W m-2 mV-1.
Example: Calculate Musing G= 0.147 mV μA-1 and C= 93.75 μA per 1000 W
m-2
M= = 72.56 W m mV
1
0.147
2 1
mV
μA
93.75 μA
1000 W m 2
−
−









−
− −
Connecting the 2220 Millivolt Adapter
If the data logger or recorder being used with this millivolt adapter has bipolar
capability, connect the positive (green) lead to the common (low) terminal, and
connect the negative (blue) lead to signal (high) input. This will help minimize
noise.
If the data logger has high, low, and ground terminals, place a jumper wire
between the common (low) and ground terminals.
If bipolar signal capability is not available, connect the positive (green) lead to
the signal input, and the negative (blue) lead to the common terminal. In this
case, use the absolute value of the multiplier.
3-2
Section 3. Millivolt Adapters