LI190SB Quantum Sensor Revision: 3/08 L I- C O R QU A NT UM Q 1 7992 C o p y r i g h t © 1 9 8 2 - 2 0 0 8 C a m p b e l l S c i e n t i f i c , I n c .
Warranty and Assistance The LI190SB QUANTUM SENSOR is warranted by CAMPBELL SCIENTIFIC, INC. to be free from defects in materials and workmanship under normal use and service for twelve (12) months from date of shipment unless specified otherwise. Batteries have no warranty. CAMPBELL SCIENTIFIC, INC.'s obligation under this warranty is limited to repairing or replacing (at CAMPBELL SCIENTIFIC, INC.'s option) defective products.
LI190SB Table of Contents PDF viewers note: These page numbers refer to the printed version of this document. Use the Adobe Acrobat® bookmarks tab for links to specific sections. 1. General Description.....................................................1 2. Specifications ..............................................................2 3. Installation....................................................................3 4. Wiring............................................................................
LI190SB Quantum Sensor 1. General Description The LI190SB quantum sensor measures photosynthetically active radiation (PAR) in the 400 to 700 nm waveband. The unit of measurement is µmoles per second per square meter (µmol s-1m-2). The quantum sensor is designed to measure PAR received on a plane surface. The indicated sensor response (Figure 1-1) is selected because it approximates the photosynthetic response of plants for which data are available.
LI190SB Quantum Sensor 2. Specifications NOTE Stability: <±2% change over a 1 year period Response Time: 10 μs Temperature Dependence: 0.15% per °C maximum Cosine Correction: Cosine corrected up to 80° angle of incidence Operating Temperature: -40 to 65°C Relative Humidity: 0 to 100% Detector: High stability silicon photovoltaic detector (blue enhanced) Sensor Housing: Weatherproof anodized aluminum case with acrylic diffuser and stainless steel hardware Size: 0.94” dia x 1.00” H (2.
LI190SB Quantum Sensor 3. Installation The LI190SB should be mounted such that it is never shaded by the tripod/tower or other instrumentation. The sensor should be mounted with the cable pointed towards the nearest magnetic pole, e.g. in the Northern Hemisphere point the cable towards the North Pole. Mounting height is not critical for the accuracy of the measurement. However, pyranometers mounted at heights of 3 m or less are easier to level and clean.
LI190SB Quantum Sensor NOTE Remove the red cap after installing the sensor. Save this cap for shipping or storing the sensor. FIGURE 3-2. 015 Pyranometer Mounting Arm FIGURE 3-3. 025 Crossarm Stand and 019ALU Crossarm 4. Wiring A schematic diagram of the LI190SB is shown in Figure 4-1. Connections to Campbell Scientific dataloggers are given in Table 4-1.
LI190SB Quantum Sensor TABLE 4-1. Connections to Campbell Scientific Dataloggers CR9000(X) CR5000 CR3000 CR1000 CR800 CR850 CR510 CR500 CR10(X) 21X CR7 CR23X Color Description Red Signal Differential High Differential High Differential High Black Signal Reference Differential Low Differential Low Differential Low Clear Shield G *Jumper to AG or with user supplied wire. FIGURE 4-1.
LI190SB Quantum Sensor Output from the LI190SB is a voltage raning from 0 to a maximum of 10 mV depending on sensor calibration and radiation level, which is measured by the datalogger using a Differential analog input channel. To measure the output, Edlog dataloggers (e.g. CR10X, CR23X) are programmed with Instruction 2 Volt(DIFF), CRBasic dataloggers (e.g. CR1000, CR3000) are programmed with the VoltDiff Instruction. Nearby AC power lines, electric pumps, or motors can be a source of electrical noise.
LI190SB Quantum Sensor 5.1 Input Range An example showing how to determine the optimum input range for a given sensor calibration and maximum photosynthetically active radiation (PAR) is given below. This is an example only. Your values will be different. -Sensor Calibration: Assume the sensor calibration is 8 µA/1000 µmoles s-1m-2 (1000 µmoles = 1 mmole). The LI190SB outputs amperage which is converted to voltage by a 604 ohm shunt resistor in the cable.
LI190SB Quantum Sensor 5.2 Example Programs The following programs measure the LI190SB every 10 seconds, and convert the mV output to µmoles s-1m-2 and mmoles m-2. Both programs output an hourly average flux (µmoles s-1m-2) and a daily total flux density (mmoles m-2). Wiring for the examples is given in Table 5-2. Multipliers in the example programs are based upon a sensor with a calibration constant of 6.45 µA/1000 µmoles s-1m-2. TABLE 5-2.
LI190SB Quantum Sensor 5.2.2 CR10X Example Program ;{CR10X} *Table 1 Program 01: 10.
LI190SB Quantum Sensor 10: Average (P71) 1: 1 Reps 2: 3 Loc [ PAR_Den ] 11: 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) 12: Set Active Storage Area (P80) 1: 1 Final Storage Area 1 2: 102 Array ID 13: Real Time (P77) 1: 1220 Year,Day,Hour/Minute (midnight = 2400) 14: Resolution (P78) 1: 1 High Resolution 15: Totalize (P72) 1: 1 Reps 2: 4 Loc [ PAR_Tot ] 16: Resolution (P78) 1: 0 Low Resolution 5.
LI190SB Quantum Sensor 6. Maintenance and Calibration DO NOT use alcohol, organic solvents, abrasives, or strong detergents to clean the diffuser element. The acrylic materials used in LI-COR light sensors can be crazed by exposure to alcohol or organic solvents, which will adversely affect the cosine response of the sensor. Clean the sensor only with water and/or a mild detergent such as dishwashing soap. Vinegar can also be used to remove hard water deposits from the diffuser element, if necessary.
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Campbell Scientific Companies Campbell Scientific, Inc. (CSI) 815 West 1800 North Logan, Utah 84321 UNITED STATES www.campbellsci.com info@campbellsci.com Campbell Scientific Africa Pty. Ltd. (CSAf) PO Box 2450 Somerset West 7129 SOUTH AFRICA www.csafrica.co.za cleroux@csafrica.co.za Campbell Scientific Australia Pty. Ltd. (CSA) PO Box 444 Thuringowa Central QLD 4812 AUSTRALIA www.campbellsci.com.au info@campbellsci.com.au Campbell Scientific do Brazil Ltda.
