INSTRUCTION MANUAL EC150 CO2/H2O Open-Path Gas Analyzer Revision: 6/14 C o p y r i g h t © 2 0 1 0 - 2 0 1 4 C a m p b e l l S c i e n t i f i c , I n c .
Limited Warranty “Products manufactured by CSI are warranted by CSI to be free from defects in materials and workmanship under normal use and service for twelve months from the date of shipment unless otherwise specified in the corresponding product manual. (Product manuals are available for review online at www.campbellsci.com.) Products not manufactured by CSI, but that are resold by CSI, are warranted only to the limits extended by the original manufacturer.
Assistance Products may not be returned without prior authorization. The following contact information is for US and international customers residing in countries served by Campbell Scientific, Inc. directly. Affiliate companies handle repairs for customers within their territories. Please visit www.campbellsci.com to determine which Campbell Scientific company serves your country. To obtain a Returned Materials Authorization (RMA), contact CAMPBELL SCIENTIFIC, INC., phone (435) 227-9000.
Precautions DANGER — MANY HAZARDS ARE ASSOCIATED WITH INSTALLING, USING, MAINTAINING, AND WORKING ON OR AROUND TRIPODS, TOWERS, AND ANY ATTACHMENTS TO TRIPODS AND TOWERS SUCH AS SENSORS, CROSSARMS, ENCLOSURES, ANTENNAS, ETC. FAILURE TO PROPERLY AND COMPLETELY ASSEMBLE, INSTALL, OPERATE, USE, AND MAINTAIN TRIPODS, TOWERS, AND ATTACHMENTS, AND FAILURE TO HEED WARNINGS, INCREASES THE RISK OF DEATH, ACCIDENT, SERIOUS INJURY, PROPERTY DAMAGE, AND PRODUCT FAILURE.
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 ......................................................... 2 4. Overview ...................................................................... 2 4.1 4.2 4.3 4.4 4.5 4.
Table of Contents 7.2 Zero and Span Procedure .................................................................. 23 8. Maintenance and Troubleshooting ..........................28 8.1 8.2 8.3 8.4 8.5 8.6 8.7 Routine Site Maintenance ................................................................. 28 Gas Analyzer Wicks .......................................................................... 28 Cleaning Analyzer Windows............................................................. 29 Zero and Span.......
Table of Contents D. Useful Equations .................................................... D-1 E. Material Safety Data Sheets (MSDS) ..................... E-1 E.1 E.2 Magnesium Perchlorate MSDS ........................................................ E-1 Decarbite MSDS .............................................................................. E-8 F. Packing Information ............................................... F-1 F.1 F.2 EC150-GH Packing Information............................................
Table of Contents 8-2. 8-3. A-1. A-2. B-1. C-1. C-2. D-1. Diagnostic Flags of Sonic Status LED .............................................. 33 Diagnostic Flags and Suggested Actions........................................... 34 Factory Default Settings .................................................................. A-1 ConfigCmd Values for Setting and Retrieving Settings ................ A-10 Filter Time Delays for Various Bandwidths....................................
EC150 CO2/H2O Open-Path Gas Analyzer 1. Introduction The EC150 is an in situ, open-path, mid-infrared absorption gas analyzer that measures the absolute densities of carbon dioxide and water vapor. The EC150 was designed for open-path eddy covariance flux measurements as part of an open-path eddy covariance measurement system. It is most often used in conjunction with the CSAT3A sonic anemometer and thermometer, which measures orthogonal wind components along with sonically determined air temperature.
EC150 CO2/H2O Open-Path Gas Analyzer Handle the EC150 carefully. The optical source may be damaged by rough handling, especially while the analyzer is powered. o Overtightening bolts will damage or deform the mounting hardware. CAUTION: o Grounding the EC100 measurement electronics is critical. Proper grounding to Earth will ensure maximum electrostatic discharge (ESD) and lightning protection and improve measurement accuracy.
EC150 CO2/H2O Open-Path Gas Analyzer • • • • • • • • • • • • • • 4.
EC150 CO2/H2O Open-Path Gas Analyzer 4.6 EC100 Electronics Module The EC100 electronics module (shown in FIGURE 4-1) controls the EC150 and optional CSAT3A sonic anemometer head. The EC100 synchronizes measurements and processes data from the EC150 and the CSAT3A. FIGURE 4-1. EC100 electronics module 4.6.1 EC100 Communications and Control The EC100 supports several serial communication interfaces, including USB, RS-485, and Synchronous Device for Measurement (SDM).
EC150 CO2/H2O Open-Path Gas Analyzer 4.6.2.1 SDM Output To use SDM data output, connect an SDM communications cable from the EC100 (see Section 6.3, Wiring and Connections) to a CR1000, CR3000, or CR5000 datalogger. On CR1000 dataloggers, the SDM protocol uses ports C1, C2, and C3. These are multipurpose control ports that are SDM-activated when an SDM instruction is used in the datalogger’s program. On CR3000 and CR5000 dataloggers, the SDM protocol uses SDM-dedicated ports SDM-C1, SDM-C2, and SDM-C3.
EC150 CO2/H2O Open-Path Gas Analyzer The algorithm uses the following environmental parameters to control the heater: • • • • • 4.8 Analyzer body temperature, measured inside the source housing (heater control does not allow the body temperature to drop below ambient air temperature) Ambient relative humidity (in humidity greater than 80% heaters will try to maintain internal temperature 2 degrees warmer than ambient) CO2 signal level (1 min average CO2 signal level; below 0.
EC150 CO2/H2O Open-Path Gas Analyzer The EC100 electronics module digitizes and process the detector data (along with ancillary data such as ambient air temperature and barometric pressure) to give the CO2 and H2O density for each chopper wheel revolution (50 Hz). This high measurement rate is beneficial when there is a need to synchronize the gas measurements with additional sensors measured by the datalogger. To prevent aliasing, measurements are filtered to a bandwidth that is specified by the user. 5.
EC150 CO2/H2O Open-Path Gas Analyzer Gas analyzer Measurement precision iii CO2 density: H2O density: Factory calibrated range CO2: H2O: Temperature: Barometric pressure: CO2 performance Zero max drift iv: Gain drift: Sensitivity to H2O: H2O performance Zero max driftiv: Gain drift: Sensitivity to CO2: 0.2 mg·m–3 (0.15 µmol·mol–1) 0.004 g·m–3 (0.006 mmol·mol–1) 0 to 1000 µmol·mol–1 0 to 72 mmol/mol (37°C dewpoint) −30° to 50°C 70 to 106 kPa ±0.55 mg·m–3·°C–1 (± 0.3 μmol·mol·°C–1) ±0.
EC150 CO2/H2O Open-Path Gas Analyzer CSAT3 sonic reporting range Full scale wind: Sonic temperature: ±65.6 m/s −50° to 60°C Auxiliary sensors vii Barometer Internal basic barometer Accuracy −30° to 0°C: 0° to 50°C: Measurement rate: Optional enhanced barometer Manufacturer: Model: Accuracy: Measurement rate: EC150 temperature sensor Manufacturer: Model: Accuracy: 5.2 ±3.7 kPa at −30°C, falling linearly to ±1.5 kPa at 0°C ±1.5 kPa 10.0 Hz Vaisala PTB110 ±0.15 kPa (−30°C to 50°C) 1.
EC150 CO2/H2O Open-Path Gas Analyzer Dimensions Head housing diameter: Head length: EC100 enclosure: Weight Analyzer and cable: EC100 electronics and EC100 enclosure: 3.2 cm (1.3 in) 29.7 cm (11.7 in) 24.1 cm x 35.6 cm x 14 cm (9.5 in x 14.0 in x 5.5 in) 2 kg (4.4 lbs) 3.2 kg (7.0 lbs) FIGURE 5-1. Optical path and envelope dimensions of EC150 analyzer head 5.
EC150 CO2/H2O Open-Path Gas Analyzer 6. Installation 6.1 Orientation During operation, the EC150 should be positioned vertically (±15°) so that the product label reads right side up and the upper arm (source) is directly above the lower arm (detector). If the sensor is being used with a sonic anemometer, the anemometer should be leveled and pointed into the prevailing wind to minimize flow distortion from the analyzer’s arms and other supporting structures. 6.
EC150 CO2/H2O Open-Path Gas Analyzer The mounting bracket for the EC50 with CSAT3A, pn 26786, allows the intake source of the CSAT3A and EC150 to be positioned at varying degrees up to approximately a 5.0 cm (2.0 in) offset. The positioning and offset is illustrated in FIGURES 6-3 and 6-4. The change in positioning allows a small but significant difference in the flux attenuation ratio.
EC150 CO2/H2O Open-Path Gas Analyzer FIGURE 6-3. Mounting position of CSAT3A and EC155 with a 4.9 cm sensor separation. FIGURE 6-4. Mounting position of CSAT3A and EC155 with a 9.7 cm sensor separation. The following steps describe the normal mounting procedure. Refer to FIGURE 6-5 and 6-6 throughout this section.
EC150 CO2/H2O Open-Path Gas Analyzer 6.2.1 Preparing the mounting structure WARNING 1. Secure a CM20X crossarm to a tripod or other vertical structure using a CM210 crossarm-to-pole bracket (pn 17767). 2. Point the horizontal arm into the direction of the prevailing wind. 3. Tighten all fitting set screws. Do not carry the EC150 by the arms or the strut between the arms. Always hold the sensor by the block where the upper and lower arms connect. 6.2.
EC150 CO2/H2O Open-Path Gas Analyzer CAUTION Avoid crashing the arms of the sensors together. The arms of the analyzer should slide in between the claws of the CSAT3A; the sonic head may need to be loosened and repositioned to do this. 10. Tighten bolts and check that the analyzer is oriented vertically such that the label is right-side-up and the upper arm (source) is directly above the lower arm (detector). 11.
EC150 CO2/H2O Open-Path Gas Analyzer EC150 Gas Analyzer Head EC150 Head-Only Mounting Bracket CM250 Leveling Mount FIGURE 6-6. Exploded view of mounting the EC150 without the CSAT3A CAUTION Over-tightening bolts will damage or deform mounting hardware. 6.2.3 Mounting EC150 without CSAT3A The instructions for mounting the EC150 without the CSAT3A should generally follow those in Section 6.2.
EC150 CO2/H2O Open-Path Gas Analyzer CAUTION Use caution when handling the EC150 gas analyzer head. The optical source may be damaged by rough handling, especially while the EC150 is powered. NOTE The CSAT3A sonic anemometer is an updated version of the CSAT3, designed to work with the EC100 electronics. An existing CSAT3 may be upgraded to a CSAT3A. Contact a Campbell Scientific application engineer for details. 6.2.
EC150 CO2/H2O Open-Path Gas Analyzer bracket (it should slide into place and be able to securely hang from the bracket), and retightening the bolts (see FIGURE 6-8). FIGURE 6-8. Exploded view of mounting the EC100 enclosure 5. Remove the EC100 enclosure desiccant from the plastic bag and put it back in the mesh pocket of the enclosure. 6. Adhere the humidity indicator card to the inside of the door of the enclosure. 6.2.
EC150 CO2/H2O Open-Path Gas Analyzer FIGURE 6-9. EC150 temperature probe FIGURE 6-10. Solar radiation shield with EC150 temperature probe 6.3 Wiring and Connections FIGURES 6-11 and 6-12 show EC100 electronics panel and the bottom of the EC100 enclosure, respectively. Refer to these figures during the wiring and connecting of the various auxiliary sensors. FIGURE 6-11.
EC150 CO2/H2O Open-Path Gas Analyzer FIGURE 6-12. Bottom of EC100 enclosure 6.3.1 Connecting the EC150 Gas Analyzer Head 1. Remove the black rubber cable entry plug (pn 26224) that is located on the bottom right of the EC100 enclosure labeled Cable 3. (This plug can be stored in the mesh pocket of the enclosure.) 2. Insert the cable entry plug that is attached to the large cable of the EC150 gas analyzer head into the vacant slot. 3.
EC150 CO2/H2O Open-Path Gas Analyzer 6.3.3 Connect the EC150 Temperature Probe 1. Unscrew the temperature connector cover which is found on the bottom of the EC100 enclosure labeled Temperature Probe (see FIGURE 6-12). 2. Insert the three-prong temperature probe connector into the female connector on the enclosure and screw it firmly in place. The EC150 temperature probe cable is approximately 3.0 m (10.0 ft) in length. 6.3.4 Ground the EC100 Electronics 1.
EC150 CO2/H2O Open-Path Gas Analyzer TABLE 6-1. EC100 SDM output to a Campbell Scientific CR1000, CR3000, or CR5000 Datalogger EC100 Channel Description Color SDM-C1 SDM Data Green SDM-C2 SDM Clock White SDM-C3 SDM Enable Brown G Digital Ground Black G Shield Clear 6.3.6 Wire Power and Ground the EC100 1. Feed cable CABLEPCBL-L (pn 21969-L) through Cable 2 at the bottom of the EC100 enclosure (see FIGURE 6-12) and attach the ends into the green EC100 power connector (pn 3768). 2.
EC150 CO2/H2O Open-Path Gas Analyzer natural elements. A zero-and span procedure should be performed after installation of the instrument to give appropriate baseline readings as a reference. A zero-and-span procedure should also be performed occasionally to assess drifts from factory calibration. In many cases, a zero and span can help resolve problems that are being experienced by the user during operating the EC150.
EC150 CO2/H2O Open-Path Gas Analyzer CAUTION 1. Remove power from the EC100/EC150. Unplugging the power cable from the EC100 is the easiest way to accomplish this. 2. Remove wicks from the snouts of the analyzer. 3. Clean windows and snouts with isopropyl alcohol and a lint-free, nonabrasive tissue or cloth as described in Section 8.3, Cleaning Analyzer Windows. Make sure any residual alcohol and water completely evaporate from the analyzer before proceeding with the zero-and-span procedure. 4.
EC150 CO2/H2O Open-Path Gas Analyzer 5. Disconnect the EC150 temperature probe from the EC100 and connect the shroud temperature probe in its place. 6. Connect the EC100 to a PC with the EC100 USB cable (pn 26563). 7. Resume power to the EC100/EC150. 8. Wait for all the Gas and Power LED status lights on the EC100 panel to turn green. 9. Launch ECMon, select the appropriate USB port, and click Connect. The main screen should now be reporting real-time CO2 and H2O concentrations. 10.
EC150 CO2/H2O Open-Path Gas Analyzer FIGURE 7-2. ECMon zero-and-span window 15. Remove the CO2 span gas from the inlet of the shroud and replace it with H2O span gas from a dew-point generator or another standard reference. As water molecules can adsorb to inside of the tubing and the shroud, it may take 30 minutes or more for the H2O concentration to stabilize. The user may increase the flow rate for the first several minutes to more quickly stabilize the system before returning it to between 0.2 and 0.
EC150 CO2/H2O Open-Path Gas Analyzer Compute the drift in instrument gain using the following equation: gain = spanactual spanmeas − zeromeas where, • • • spanactual = known concentration of the span gas spanmeas = measured concentration of the span gas zeromeas = measured concentration in zero gas Note that in the zero-and-span window of ECMon, spanactual is reported to the right of the box where the user enters the span dewpoint temperature.
EC150 CO2/H2O Open-Path Gas Analyzer 8. Maintenance and Troubleshooting EC150 operation requires six maintenance tasks: • Routine site maintenance • Wick maintenance • Analyzer window cleaning • Zero and span • Replacing the analyzer desiccant/scrubber bottles • Factory recalibration 8.1 Routine Site Maintenance The following items should be examined periodically: 8.2 • Check the humidity indicator card in the EC100 enclosure. If the highest dot has turned pink, replace the desiccant bags.
EC150 CO2/H2O Open-Path Gas Analyzer The bottom wick is installed in a similar manner, except the long seam should be aligned with the long side of the bottom snout. Once in place, the wicks should fit snuggly over the cylindrical part of the snout without any creases or wrinkles. The windows should be cleaned after the installation of the wicks to ensure that there are no fingerprints left on critical surfaces. See Section 8.3, Cleaning Analyzer Windows, for specifics on cleaning the EC150 windows.
EC150 CO2/H2O Open-Path Gas Analyzer Performing frequent zero-and-span procedures when the instrument is first put into use to determine the drift from factory calibration, will give a good guideline for the frequency that the procedure should be performed. To perform a maintenance zero and span, follow the same steps as in Section 7, Zero and Span. 8.
EC150 CO2/H2O Open-Path Gas Analyzer FIGURE 8-2. Replacing the desiccant/CO2 scrubber bottles 8.6 Factory Recalibration When the EC150 is manufactured, it goes through an extensive calibration process, covering a wide range of temperatures, pressures, and gas concentrations.
EC150 CO2/H2O Open-Path Gas Analyzer 8.7 Troubleshooting 8.7.1 Data Loss During Precipitation Events In extremely humid environments or after a precipitation event, data loss can occur. Wicks on the analyzer windows help mitigate some of these data loss events but cannot control for all conditions. In addition to wicking, heaters in the snouts can aid in the prevention of data loss during precipitation and condensation events. The heaters are automatically controlled by the EC100 electronics.
EC150 CO2/H2O Open-Path Gas Analyzer power supply cable is adequate gage and does not cause excessive voltage drop. SONIC Status LED • The SONIC status LED will turn red if there is no CSAT3A connected to the EC100 electronics or if any of the six sonic diagnostic flags are set. Please refer to TABLE 8-2 and to the CSAT3A instruction manual for more detail information on sonic diagnostic flags. TABLE 8-2.
EC150 CO2/H2O Open-Path Gas Analyzer If any of the remaining 22 flags are set, the master flag (BAD_DATA) is set as well, so that the user can filter data based on this flag only. When this flag is set, more detailed information about the nature of the problem can be obtained from the 22 slave flags.
EC150 CO2/H2O Open-Path Gas Analyzer TABLE 8-3. Diagnostic Flags and Suggested Actions Flag Number Flag Name Comments 3 Motor Speed Set when the motor speed is outside the prescribed limits. It may occasionally be set for short periods of time (10 to 15 seconds), but if it persists, the user should consult with a Campbell Scientific application engineer. 4 TEC Temperature Set when the infrared detector temperature is outside the prescribed limits.
EC150 CO2/H2O Open-Path Gas Analyzer TABLE 8-3. Diagnostic Flags and Suggested Actions Flag Number 36 Flag Name Comments 10 Ambient Temperature Set when the ambient temperature is below −30°C or above 55°C or when the air temperature sensor is not connected. If the user enters a fixed temperature, this temperature must be within the range −30° to 55°C.
EC150 CO2/H2O Open-Path Gas Analyzer TABLE 8-3. Diagnostic Flags and Suggested Actions Flag Number Flag Name Comments 18 CO2 Signal Strength Set if the ratio of the CO2 measurement and the CO2 reference signals are outside prescribed limits. It can be turned on when the measurement path is obstructed by insects, dust, precipitation, condensation etc. If it persists, consult with a Campbell Scientific application engineer.
EC150 CO2/H2O Open-Path Gas Analyzer 38
Appendix A. EC150 Settings Operation of the EC150 can be customized by changing the values of the settings. Factory defaults will work well for most applications, but the user may adjust the settings with a PC using either the ECMon software (see Appendix A.3, ECMon) or the Device Configuration Utility (see Appendix A.4, Device Configuration Utility), or with a datalogger using the EC100Configure() CR Basic instruction (see Appendix A.5, EC100Configure() Instruction).
Appendix A. EC150 Settings A.2.1 SDM Address This parameter must be set to use SDM output from the EC100. See Section 4.6.2.1, SDM Output, for details on using SDM output. Each SDM device on the SDM bus must have a unique address. The EC150 has a factory default SDM address of 1, but may be changed to any integer value between 0 and 14. The value 15 is reserved as an SDM group trigger. The SDM address is stored in non-volatile memory of the EC100 electronics. A.2.
Appendix A. EC150 Settings The Unprompted Output setting is stored in non-volatile memory of the EC100 electronics. A.2.5 RS-485 Baud Rate If the unprompted output mode is set to RS-485, the RS-485 Baud Rate parameter determines the baud rate. Otherwise this setting is not used. The RS-485 baud rate defaults to 115200 bps, although the user may enter another value. The RS-485 Baud Rate setting is stored in non-volatile memory of the EC100 electronics. A.2.
Appendix A. EC150 Settings The Fixed Temperature Value setting is stored in non-volatile memory of the EC100 electronics. A.2.10 Pressure Sensor There are three options for measuring barometric pressure for the EC150 that have different corresponding Pressure Sensor settings. 1. The EC100 has an on-board barometer that Campbell Scientific refers to as the EC100 basic barometer. This barometer is mounted on the EC100 electronics board as shown in FIGURE A-1.
Appendix A. EC150 Settings FIGURE A-2. Location of EC100 enhanced barometer FIGURE A-3.
Appendix A. EC150 Settings 3. The option of a third barometer choice is also available but is rarely used. A user-supplied barometer option can also be programmed in the EC100 electronics. This setting determines which pressure sensor will be used to measure the barometric pressure. User-supplied Barometer: When a user supplies a barometer, the setting should be changed to User Supplied and the appropriate values for gain and offset must be entered.
Appendix A. EC150 Settings A.2.12 Heater Control When set to automatic, this setting applies a voltage between 0 and 4600 mV to heaters near the optical windows of the analyzer. Heated windows inhibit the formation of condensation, such as dew and frost, and help the analyzer recover more quickly when precipitation has blocked the optical path. The Heater Control setting is stored in non-volatile memory in the EC150 head. A.2.13 Head Power Off When enabled, the EC150 gas head is turned off.
Appendix A. EC150 Settings FIGURE A-4. Main screen of ECMon FIGURE A-5.
Appendix A. EC150 Settings A.4 Device Configuration Utility The Device Configuration Utility software may also be used to change settings, although ECMon is generally preferred as the user interface is more intuitive. Device Configuration may be downloaded from the EC150 & EC155 Support CD (pn 27007), or at www.campbellsci.com/downloads. Device Configuration requires a USB driver to communicate with the EC100, similar to ECMon. See Appendix A.3, ECMon, for notes on installing a USB driver.
Appendix A. EC150 Settings The instruction syntax is: EC100Configure(Result,SDMAddress,ConfigCmd,DestSource) Result is a variable that contains a value indicating the success or failure of the command. A result code of 0 means that the command was successfully executed. If reading a setting, 0 in the result code means that the value in the DestSource variable is the value the desired setting has in the EC150.
Appendix A. EC150 Settings TABLE A-2.
Appendix A. EC150 Settings complete. To perform CO2 span, the CO2 Span Concentration setting (ConfigCmd 12) must be written to the proper value in ppm CO2 prior to setting the Span/Zero Control setting (ConfigCmd 11) to 2. After the CO2 span is completed, the value of the Span/Zero Control setting will change to –2. H2O span is similar to CO2. First the H2O Dew Point value (ConfigCmd 13) must be written to the desired value. Then the Span/Zero Control setting is set to 3.
Appendix B. Filter Bandwidth and Time Delay The EC100 measures CO2 and H2O from the EC150 gas analyzer head. It will also measure wind velocity and sonic temperature if the optional CSAT3A sonic head is being used. EC100 measurements occur at 100z and then a userselectable, low-pass filter is applied. The available filter bandwidths are 5, 10, 12.5, 20, and 25 Hz. FIGURE B-1 shows the amplitude response of these filters.
Appendix B. Filter Bandwidth and Time Delay FIGURE B-2. Frequency response comparison of EC100 10-Hz bandwidth and a 50-msec moving average The ideal eddy-covariance filter is one that is wide enough to preserve the lowfrequency signal variations that transport flux, yet narrow enough to attenuate high-frequency noise.
Appendix B. Filter Bandwidth and Time Delay provides a constant time delay for all spectral components within each filter’s pass band. TABLE B-1. Filter Time Delays for Various Bandwidths Bandwidth (Hz) Time Delay (ms) 5 800 10 400 12.5 320 20 200 25 160 The following examples show how to use TABLE B-1.
Appendix B.
Appendix C. Alternate EC100 Outputs C.1 USB or RS-485 Output C.1.1 Specifications Digital RS-485 Data type: Output Rate viii: Baud rateviii: USB Data type: Output rateviii: ASCII 5 to 50 Hz 1200 to 230400 bps USB ASCII 10, 25, or 50 Hz C.1.2 Detailed Information In contrast to the SDM output mode, which is prompted by a datalogger, data can also be output from the EC100 via USB or RS485 in an unprompted mode.
Appendix C. Alternate EC100 Outputs TABLE C-1. USB and RS-485 Output Elements Data Element 5 6 7 8 9 10 11 12 Description 14 Sonic Diagnostic Flag CO2 Density H2O Density Gas Diagnostic Flag Air Temperature Air Pressure CO2 Signal Strength H2O Signal Strength Pressure Differential (used for EC155 only, disregard for EC150) Counter 15 Signature 13 Units or comments mg·m-3 g·m-3 °C kPa Nominally 0.0 to 1.0 Nominally 0.0 to 1.0 kPa Arbitrary Arbitrary in hexadecimal FIGURE C-1.
Appendix C. Alternate EC100 Outputs //signature(), signature algorithm. // Standard signature is initialized with a seed of 0xaaaa. // Returns signature. unsigned short signature( unsigned char* buf, int swath, unsigned short seed ) { unsigned char msb, lsb; unsigned char b; int i; msb = seed >> 8; lsb = seed; for( i = 0; i < swath; i++ ) { b = (lsb << 1) + msb + *buf++; if( lsb & 0x80 ) b++; msb = lsb; lsb = b; } return (unsigned short)((msb << 8) + lsb); } C.2 Analog Output C.2.
Appendix C. Alternate EC100 Outputs TABLE C-2. Multipliers and Offsets for Analog Outputs C-4 Density (mg·m-3) Voltage Output Multiplier (mg·m-3 V-1) Offset (mg·m-3) CO2 386.32 −102.59 H2O 8.65 −2.
Appendix D. Useful Equations The following table lists all the variables and constants used in the equations below: TABLE D-1. Variables and Constants Variable or Constant Description Units ρc CO2 mass density mg·m-3 ρv H2O mass density g·m-3 ρd Mass density of dry air g·m-3 Xc Xv CO2 molar mixing ratio (concentration relative to dry air) H2O molar mixing ratio (concentration relative to dry air) Mc Molecular weight of CO2 44 mg·mmol-1 Md Molecular weight of dry air 0.
Appendix D. Useful Equations XvP P − M d 1000 + X v ρd = R(T + 273.15) PM (D-4) X d v 1 − ρ d = R(T + 273.15) 1000 + X v (D-5) Dew Point from Molar Mixing Ratio Td = 240.97 Td _ tmp (D-6) 17.502 − Td _ tmp XvP Td _ tmp = ln 0.61121 ⋅ f (1000 + X v ) ( ) ( (D-7) ) f = 1.00072 + 3.2 ×10 −5 P + 5.9 ×10 −9 PT 2 (D-8) Water Vapor Molar Mixing Ratio from Dew Point Xv = e 1000 P−e (D-9) 17.502Td e = 0.61121⋅ f ⋅ EXP 240.
Appendix D. Useful Equations Vapor Pressure from Molar Mixing Ratio and Water Vapor Density e= XvP 1000 + X v (D-12) e= ρ v R(T + 273.15) Mv (D-13) Equations (D-1) and (D-2) were derived from: Leuning, R.: 2005, “Measurements of Trace Gas Fluxes in the Atmosphere Using Eddy Covariance: WPL Corrections Revisited”, Handbook of Micrometeorology, 29, 119-132. Equations (D-3), (D-4), (D-5), (D-7), (D-9), and (D-13) were derived from: Bolton, D.
Appendix D.
Appendix E. Material Safety Data Sheets (MSDS) E.
Appendix E.
Appendix E.
Appendix E.
Appendix E.
Appendix E.
Appendix E.
Appendix E. Material Safety Data Sheets (MSDS) E.
Appendix E.
Appendix E.
Appendix F. Packing Information F.
Appendix F. Packing Information F.
Campbell Scientific Companies Campbell Scientific, Inc. (CSI) 815 West 1800 North Logan, Utah 84321 UNITED STATES www.campbellsci.com • info@campbellsci.com Campbell Scientific Centro Caribe S.A. (CSCC) 300 N Cementerio, Edificio Breller Santo Domingo, Heredia 40305 COSTA RICA www.campbellsci.cc • info@campbellsci.cc Campbell Scientific Africa Pty. Ltd. (CSAf) PO Box 2450 Somerset West 7129 SOUTH AFRICA www.csafrica.co.za • cleroux@csafrica.co.za Campbell Scientific Ltd.
