1. Manuals
  2. Brands
  3. METER Manuals
  4. Weather Station
  5. ATMOS 41
  6. User manual

METER ATMOS 41 User Manual

Hide thumbs Also See for ATMOS 41:
Table of Contents

Advertisement

Quick Links

Download this manual
ATMOS 41

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the ATMOS 41 and is the answer not in the manual?

Questions and answers

Related Manuals for METER ATMOS 41

Summary of Contents for METER ATMOS 41

  • Page 1 ATMOS 41...

  • Page 2: Table Of Contents

    ....................1 2. Operation ....................2 2.1 Installation ....................2 2.2 Connecting ....................3 2.2.1 Connect to METER Logger ..............4 2.2.2 Connect to Non-METER Logger ............5 2.3 Communication ..................6 3. System ......................7 3.1 Specifications .................... 7 3.2 Pyranometer ....................
  • Page 3 3.12 Measurements with METER Loggers ............23 4. Service ....................... 25 4.1 Calibration ....................25 4.2 Recalibration Recommendations ............. 26 4.3 Cleaning and Maintenance ............... 26 4.4 Update Firmware ..................28 4.5 Troubleshooting ..................28 4.6 Customer Support..................30 4.7 Terms and Conditions ................31 References ....................

  • Page 5: Introduction

    All sensors are integrated into a single, small form-factor unit, requiring minimal installation effort. A robust, no moving parts design that prevents errors because of wear or fouling make the weather station ideal for long-term, remote installations. ATMOS 41 can be used for a variety of applications: •...

  • Page 6: Operation

    Please read all instructions before operating the ATMOS 41 to ensure it performs to its full potential. PRECAUTIONS METER sensors are built to the highest standards, but misuse, improper protection, or improper installation may damage the sensor and possibly void the manufacturer’s warranty. Before integrating ATMOS 41 into a system, follow the recommended installation instructions and have the proper protections in place to safeguard sensors from damage.

  • Page 7: Connecting

    Secure the System Tighten the V-bolt nuts by hand until hand-tight, and then gently tighten with a wrench, securing the ATMOS 41 flat and tight against the top of the stand. CAUTION: Do not overtighten V-bolt. Secure and Protect Cables NOTE: Improperly protected cables can lead to severed cables or disconnected sensors.

  • Page 8: Connect To Meter Logger

    The ATMOS 41 comes standard with a 5-m cable. It may be purchased with custom cable lengths for an additional fee (on a per-meter basis). In some instances, the cable can be extended beyond 75 m by the user, but this is discouraged for a variety of reasons. Please...

  • Page 9: Connect To Non-Meter Logger

    ATMOS 41 sensors can be ordered with stripped and tinned (pigtail) wires for use with screw terminals. Refer to the third-party logger manual for details on wiring. Connect the ATMOS 41 wires to the data logger as illustrated in Figure 2...

  • Page 10: Communication

    ATMOS 41 Integrator Guide. The SDI-12 protocol requires that all sensors have a unique address. ATMOS 41 sensor factory default is an SDI-12 address of 0. To add more than one SDI-12 sensor to a bus, the sensor address must be changed as described in these steps.

  • Page 11: System

    ATMOS 41 3. SYSTEM This section describes the ATMOS 41 All-in-One Weather Station system. 3.1 SPECIFICATIONS MEASUREMENT SPECIFICATIONS Solar Radiation Range 0–1750 W/m Resolution 1 W/m Accuracy ±5% of measurement typical Precipitation Range 0–400 mm/h Resolution 0.017 mm Accuracy ±5% of measurement from 0 to 50 mm/h...
  • Page 12 SYSTEM Relative Humidity Range 0–100% RH Resolution 0.1% RH Accuracy Varies with temperature and humidity, ±3% RH typical Figure 5 RH sensor accuracy Air Temperature Range –50 to 60 °C Resolution 0.1 °C Accuracy ±0.6 °C Humidity Sensor Temperature Range –40 to 50 °C Resolution 0.1 °C Accuracy...
  • Page 13 ATMOS 41 Horizontal Wind Speed Range 0–30 m/s Resolution 0.01 m/s Accuracy The greater of 0.3 m/s or 3% of measurement Wind Gust Range 0–30 m/s Resolution 0.01 m/s Accuracy The greater of 0.3 m/s or 3% of measurement Wind Direction Range 0°–359°...
  • Page 14 3.6 VDC continuous Typical Maximum 15.0 VDC continuous NOTE: The ATMOS 41 must be continulously powered to work properly. NOTE: For the ATMOS 41 to meet digital logic levels specified by SDI-12, it must be excited at 3.9 VDC or greater.
  • Page 15 Digital Output Voltage (logic high) Minimum Typical 3.6 V Maximum NOTE: For the ATMOS 41 to meet digital logic levels specified by SDI-12, it must be excited at 3.9 VDC or greater. Power Line Slew Rate Minimum 1.0 V/ms Typical...

  • Page 16: Pyranometer

    Solar radiation is measured by a pyranometer that is integrated into the lip of the rain gauge funnel at the top of the ATMOS 41. Designed, manufactured, and calibrated by experts at Apogee Instruments, the miniature pyranometer uses a silicon-cell sensor to measure the total incoming (direct and diffuse) solar radiation.

  • Page 17: Anemometer

    Out of level, the pyranometer will overestimate some portions of the day while under- estimating others. Ensure accurate solar radiation measurements by carefully leveling the ATMOS 41 at installation. Bird droppings and other soiling of the domed sensor surface will cause serious errors in pyranometer measurements. Check the sensor regularly to make sure it is clean and check data often to identify possible problems.

  • Page 18: Vapor Pressure/Relative Humidity Sensor

    Figure 7 Anemometer The ATMOS 41 measures wind speed every 10 s and keeps a running average of the last 10 measurements. If an instantaneous measurement is more than eight times the running average, the instantaneous measurement is rejected. It is not reported as the maximum gust or included in the data that are averaged over the output interval.
  • Page 19 (e.g., evaporation, transpiration, and distribution of water vapor). Therefore, vapor pressure is a much more useful measure of atmospheric moisture than relative humidity. The METER ZENTRA system calculates and outputs vapor pressure deficit (VPD) in the standard data stream. VPD is simply ) –...

  • Page 20: Rain Gauge

    Precipitation maximum intensity calculation is capped at 280 mm/h, available from METER data loggers and software. IMPORTANT: The ATMOS 41 must be within approximately ±2 degrees of dead level (0, 0) in both the X and Y directions to accurately measure rainfall.

  • Page 21: Temperature Sensor

    ATMOS 41 Before replacing the cover, be sure to reattach the pyranometer connector by mating the two halves of the white connector and seating firmly together until the tabs lock. NOTE: The connector is polar so it can only mate in one orientation.

  • Page 22: Lightning Sensor

    Plug the weather station stereo connector into the PROCHECK stereo port. Press MENU to navigate to the Configuration tab Scroll down to ATMOS 41 Config. Press ENTER. Press ENTER to select Strike Reject Lvl. Figure 11 ATMOS 41 configuration screen using PROCHECK The Strike Reject Lvl adjusts the lightning sensor threshold used to differentiate between man-made electrical noise and lightning strikes.

  • Page 23: Barometric Pressure Sensor

    Regularly check X and Y tilt data to ensure the ATMOS 41 is level; if it has tilted, return to the site and level again. Even a slightly off-level ATMOS 41 will cause errors in the solar radiation measurement, and a 2° tilt can cause large errors in the rainfall measurement. Although this sensor may be used to level the instrument, it is much easier to use the small bubble level on the bottom of the anemometer plate.
  • Page 24 SYSTEM Here is the frequency of the sound (Hz). When the air is moving, the speed of sound is the sum of the wind speed and the speed of sound in still air. The anemometer transmits a sound pulse in a forward direction, then a similar pulse in the reverse direction. The difference in between the two points is computed.

  • Page 25: Temperature

    ATMOS 41 The wind measurement through more frequent SDI-12 commands requires 42 ms to complete. An additional 60 ms are required for the computations to determine phase differences. The anemometer samples every 10 s (or more often if requested). The gust speed reported is the highest instantaneous wind speed measured during the selected averaging interval (must be >20 s or gusts will equal speed).

  • Page 26: Limitations

    SYSTEM Table 2 Optimized values for air temperature correction (J mol (W/m –1 –1 0.295 0.00083 0.0984 29.3 352.3 Figure 12 Corrected air temperature comparison with the aspirated radiation shield using 1-min measurement intervals Figure 12 shows the results from the temperature correction compared to the aspirated temperature, which shows data sampled at 1 min and not averaged over time.

  • Page 27: Heavy Rain And Strong Wind

    ATMOS 41 lightning and rainfall measurements can be adversely affected by high level Electromagnetic Interference (EMI), such as that produced by high voltage power transmission lines. Be sure to locate the ATMOS 41 far from such sources of EMI. 3.12 MEASUREMENTS WITH METER LOGGERS METER EM60G and ZENTRA series data loggers query the ATMOS 41 once every minute...
  • Page 28 SYSTEM Table 3 ATMOS 41 output quantities processed in data logger (continued) Data Saved by Logger Each Measurement Interval Measurement Data Output Every Minute = number of minutes) Average of six 10-s wind Weighted direction calculated from Wind direction speed measurements in both horizontal wind vectors horizontal wind vectors Maximum of six 10-s wind...

  • Page 29: Service

    The accuracy of each ATMOS 41 rain gauge is verified at a single rainfall rate during the manufacturing and quality assurance (QA) process. A subsample of rain gauges undergoes a more in-depth accuracy verification each month as part of routine QA procedures.

  • Page 30: Recalibration Recommendations

    ATMOS 41 body. This geometry is held to within 0.025-mm specifications through CNC milling procedures. Orientation of the ATMOS 41 toward North will introduce more error in the wind direction measurement than sensor geometry.
  • Page 31 ATMOS 41 Rain funnel (Figure 16) Pyranometer (Figure 16) Ultrasonic transducer openings (Figure 13) Sintered glass reflection plate (Figure 7) Clean the ATMOS 41 body. Scrub with light to medium pressure using a warm, damp cloth. Clean around posts and between crevices using a dry brush.

  • Page 32: Update Firmware

    Instructions for updating ATMOS 41 firmware (metergroup.com/environment/ articles/updating-atmos-41-firmware/). Please consult with Customer Support about any questions about the necessity or process of updating firmware on ATMOS 41. 4.5 TROUBLESHOOTING Table 5 Troubleshooting the ATMOS 41 Problem Possible Solutions Check power to the sensor.
  • Page 33 ATMOS 41 Table 5 Troubleshooting the ATMOS 41 (continued) Problem Possible Solutions Remove any debris from rain gauge funnel. The ATMOS 41 must be within approximately ±2 degrees of dead level (0, 0) in both the X and Y directions to accurately measure rainfall. If not within this range, drops from the flared hole can miss the gold electrodes entirely.

  • Page 34: Customer Support

    SERVICE Table 5 Troubleshooting the ATMOS 41 (continued) Problem Possible Solutions Check the temperature needle to be sure it is not pushed in (pushing in the temperature sensor will break the thermistor wires and stop measurement). No temperature reading Do not to abuse the temperature sensor needle when cleaning, because its very delicate lead wires can be easily damaged.

  • Page 35: Terms And Conditions

    NOTE: For products purchased through a distributor, please contact the distributor directly for assistance. 4.7 TERMS AND CONDITIONS By using METER instruments and documentation, you agree to abide by the METER Group, Inc. USA Terms and Conditions. Please refer to metergroup.com/terms-conditions...

  • Page 36: References

    REFERENCES REFERENCES Campbell, Gaylon S. and Michael H. Unsworth. 1979. An Inexpensive Sonic Anemometer for Eddy Correlation. Journal of Applied Meteorology. 18 (8):1072–1077. Buck, Arden L. 1981. New Equations for Computing Vapor Pressure and Enhancement Factor. Journal of Applied Meteorology. 20 (12):1527–1432. Robinson, R.A.

  • Page 37: Index

    INDEX INDEX lightning distance 9, 24, 26 lightning strike 9, 24, 26 anemometer 13–19 maximum rainfall rate 24 applications 1 precipitation/rainfall 7, 22–23, 24, 25 relative humidity 8, 25, 26 solar radiation 7, 12–13, 23, 25, 26 tilt 9, 19, 24, 26 barometric pressure sensor 19, 26 vapor pressure 7, 14, 24, 25 wind direction 9, 13, 24, 26...
  • Page 38 INDEX INDEX temperature sensor 17–18, 21–22 terms and conditions 31 theory air temperature 21–22 lightning 18 precipitation 16–17 relative humidity 14–15 solar radiation 12–13 vapor pressure 14–15 wind 13, 19–21 tilt sensor 19 troubleshooting 28–30 vapor pressure sensor 14–16, 26 ZENTRA logger 4, 15, 23–24 ZENTRA Cloud 4...
  • Page 39 18192-03 8.9.2019 METER Group, Inc. USA 2365 NE Hopkins Court Pullman, WA 99163 T: +1.509.332.2756 F: +1.509.332.5158 E: info@metergroup.com W: metergroup.com METER Group AG Mettlacher Straße 8, 81379 München T: +49 89 1266520 F: +49 89 12665220 E: info.europe@metergroup.com W: metergroup.de...

Table of Contents