RoHS 3 compliant using exemption 6c. Further note that Apogee Instruments does not specifically run any analysis on our raw materials or end products for the presence of these substances, but rely on the information provided to us by our material suppliers.
SU-200 series outputs an analog voltage that is directly proportional to UV-A radiation incident on a planar surface (does not have to be horizontal) where the radiation emanates from all angles of a hemisphere. SU-221 sensors output a digital signal using SDI-12 communication protocol.
SENSOR MODELS This manual covers the SDI-12 protocol UV-A sensor model SU-221 (in bold below). Additional models are covered in their respective manuals. Model Signal SU-200 0-10 mV SU-202 0- 2.5 V SU-205 0- 5 V SU-221 SDI-12 Sensor model number and serial number are located on the bottom of the sensor.
(316), M8 connector Calibration Traceability Apogee UV series sensors are calibrated through side-by-side comparison to the mean of four transfer standard UV sensors under UV-enhanced T5 fluorescent tubes. The transfer standard UV sensors are calibrated through side- by-side comparison to an Apogee model PS-300 spectroradiometer under sunlight (clear sky conditions) in Logan, Utah.
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Directional, or cosine, response is defined as the measurement error at a specific angle of radiation incidence. Directional error for Apogee SU-200 series UV-A sensors is approximately ± 2 % and ± 5 % at solar zenith angles of 45° and 75°, respectively.
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Spectral Response Spectral response estimate of Apogee SU- 200 UV-A sensors. Spectral response was modeled from sensitivity of the photodetector and transmittance of the diffuser.
Mount the sensor to a solid surface with the nylon mounting screw provided. To accurately measure UV-A incident on a horizontal surface, the sensor must be level. An Apogee Instruments model AL-100 Leveling Plate is recommended to level the sensor when used on a flat surface or being mounted to surfaces such as wood. To facilitate mounting on a mast or pipe, the Apogee Instruments model AL-120 Solar Mounting Bracket with Leveling Plate is recommended.
CABLE CONNECTORS Apogee sensors offer cable connectors to simplify the process of removing sensors from weather stations for calibration (the entire cable does not have to be removed from the station and shipped with the sensor). The ruggedized M8 connectors are rated IP68, made...
OPERATION AND MEASUREMENT The SU-221 UV-A sensor has a SDI-12 output, UV radiation is returned in digital format. Measurement of SU-221 UV-A sensors requires a measurement device with SDI-12 functionality that includes the M or C command. Wiring White: Positive (signal from sensor)
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“!”. SDI-12 language supports a variety of commands. Supported commands for the Apogee Instruments SU-221 UV-A sensors are listed in the following table (“a” is the sensor address. The following ASCII Characters are valid addresses: “0-9” or “A-Z”).
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Make Measurement Command: M! The make measurement command signals a measurement sequence to be performed. Data values generated in response to this command are stored in the sensor's buffer for subsequent collection using “D” commands. Data will be retained in sensor storage until another “M”, “C”, or “V” command is executed.
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0C2! 000101<cr><lf> 0D0! +20.0 0C3! 000101<cr><lf> 0D0! 0+90.2<cr><lf> where 30.0 is watts and 1.0 is mV and 20.0 is µmol Change Sensor Address: aAn! The change sensor address command allows the sensor address to be changed. If multiple SDI-12 devices are on the same bus, each device will require a unique SDI-12 address.
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UV-A Measurements and Spectral Errors Apogee Instruments model SU-200 UV-A sensors are calibrated to measure ultraviolet radiation from the sun between 300 and 400 nm in Watts per square meter. In addition to naturally occurring UV-A radiation from the sun, there are many electric light sources that emit UV-A radiation (e.g., cool white fluorescent, metal halide, mercury arc, and germicidal lamps).
The vinegar should be allowed to do the cleaning, not mechanical force. Never use an abrasive material or cleaner on the diffuser. It is recommended that UV-A sensors be recalibrated every two years. See the Apogee webpage for details regarding return of sensors for recalibration (http://www.apogeeinstruments.com/tech-support-recalibration-...
SDI-12 protocol limits cable length to 60 meters. For multiple sensors connected to the same data line, the maximum is 600 meters of total cable (e.g., ten sensors with 60 meters of cable per sensor). See Apogee webpage for details on how to extend sensor cable length (http://www.apogeeinstruments.com/how-to-make-a-...
RETURN AND WARRANTY POLICY RETURN POLICY Apogee Instruments will accept returns within 30 days of purchase as long as the product is in new condition (to be determined by Apogee). Returns are subject to a 10 % restocking fee. WARRANTY POLICY...
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84321, USA 5. Upon receipt, Apogee Instruments will determine the cause of failure. If the product is found to be defective in terms of operation to the published specifications due to a failure of product materials or craftsmanship, Apogee Instruments will repair or replace the items free of charge.
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