TEST & CALIBRATION FACILITIES


Surface Instruments Laboratory, It is an important wing of the Surface Instrument Division, Pune. The Division has been providing valuable services in all aspects of testing, calibration and standardization of surface meteorological instruments. The surface calibration lab maintains national and working standards. All surface meteorological equipments installed at conventional observatories are checked and compared with portable standards once a year for ensuring accurate measurements. Portable standards are traceable to national standards. National Standards are regularly compared and calibrated against International / WMO standards.
The Laboratory is recognised by Bureau of Indian Standards as the Centre for certification of indigenously made meteorological instruments including thermometers and rain measures. Each instrument submitted is carefully assessed and evaluated before issuing certification.
The laboratory has the following calibration facilities :
  • Wind Tunnel for calibration of Anemometers and wind sensors.
  • Dead Weight Testers for calibration of Digital Barometers and Pressure Sensors.
  • Temperature Calibration Bath liquid-in-glass thermometers.
  • Environmental Calibration Chambers for testing of autographic instruments like Thermograph, Hygrograph and Barograph.
Central Radiation Laboratory Radiation measurements are routinely made at Pune as early as 1932 with specific objectives. By 1957, measurements started at four stations as part of IGY Programme. The network now consists of 45 stations where various radiation parameters are being measured. This network is being maintained by the Central Radiation Laboratory The Laboratory is designated as an RA-II Regional Radiation Centre by WMO. It is also the National Radiation Centre having a hierarchy of Radiation Standards including Primary, Secondary, First-Class etc. Standards.


Sr.No. Met Parameter Photograph Standard Instruments
1 Pressure Gas Piston Gauge
  • It is a primary standard for pressure calibration.
  • Make: Ruska, Model: 2465
  • Range of Calibration: 50 to 1100 hPa at different pressure levels.
Digital pressure Indicator(DPI)
  • Standard instrument for calibration of pressure sensors available in the lab.
  • Make: Druck - GE Sensing, Model: Pace 1000
  • Range of Calibration: 50 to 1100 hPa at different pressure levels.
  • The standards are traceable to National Physical Laboratory, New Delhi standards.
2 Temperature Liquid Bath
  • All types of thermometers are calibrated using Temperature Calibration Bath at 5 points of temperature readings available in the lab.
  • In this liquid bath, liquid used below 0 Deg. - Ethanol/Methanol and above 0 Deg. - distilled water.
  • Range: -50 deg C to +100 deg C
  • Accuracy = 0.00
Standard Platinum Resistance Thermometer
  • All types of thermometers are calibrated against Standard Platinum Resistance Thermometer for positive as well as negative temperatures.
  • Range: -50 deg C to +100 deg C
  • Accuracy = 0.00
  • The standards are traceable to National Physical Laboratory, New Delhi standards.
Standard Thermometer readout unit with probe
  • All types of thermometers are calibrated against the probe of Standard Thermometer for positive as well as negative temperatures.
  • Range: -50 deg C to +100 deg C
  • Accuracy = 0.00
  • The standards traceable to National Physical Laboratory, New Delhi standards periodically.
3 Wind Airmeter
  • It is a primary standard for obtaining wind speed.
  • One full rotation in the airmeter is equivalent to 100m. Time taken for one full rotation is taken and accordingly wind speed is calculated.
Wind Tunnel Range: 0 to 35 mps
  • All types of anemometers are calibrated in Wind Tunnel.
  • Range: 0 to 35 mps. Readings of 8 points are taken.
  • Comparison with the standards and corrections are given accordingly.
Wind Tunnel Range: 0 to 70 mps
  • All types of anemometers are calibrated in Wind Tunnel.
  • Range: 0 to 70 mps. Readings of 8 points are taken.
  • Comparison with the standards and corrections are given accordingly.
Windvane
    Wind vanes are tested /calibrated for conformity to IS:5799 - 1970.
5 Humidity Environmental Test Chamber
    Thermographs, Hair Hygrographs and Temperature - Humidity sensors are calibrated in Environmental Test Chamber.
6 Precipitation

Standard Burrette-Pippete Apparatus
    1. Non-recording rain-gauges are tested for conformity to IS: 5225-1992(First Revision).
    2. Self recording rain-gauges are calibrated for conformity to IS:5235-1992(First Revision)
    3. One litre water is poured into the Tipping Bucket Raingauge at three different intensities and percentage error in the measurement of rainfall is observed.
    4. Rain Measures are calibrated against standards maintained in this office for conformity to IS: 4849-1992(First Revision).
7 Evaporation Evaporimeter
    Evaporimeters are tested /calibrated for conformity to relevant BIS Specifications.
8 Sunshine Duration Sunshine Recorders
    Sunshine recorders are tested /calibrated for conformity to the BIS Specifications IS: 7243-1974.
9 Testing of Autographic Charts Humidity Chamber
    Autographic charts are tested for conformity to the BIS Specifications IS: 5947-1970.
10 Testing of Clock-Drums BIS Specification
    Clock-drums are tested for conformity to the BIS Specifications IS: 5924-1988 (First Revision).
11 Solar Radiation



Radiation Standards
  • Central radiation laboratory is World Meteorlogical Organisation (WMO) recognized Regional Radiation Centre of RA-II region as well as National Radiation Centre.
  • It is having a hierarchy of standard instruments including primary, secondary and touring standards.
  • One of the primary standards is calibrated with reference to World Standard Group (WSG) of instruments once in 5 years.
  • The inter-comparison is carried out at World Radiation Centre, Davos (WRC), Switzerland on behalf of World Meteorlogical Organisation (WMO).

  • All types of pyranometers, pyheliometers and net pyrradiometers are calibrated with reference to standards maintained in the lab.
  • Calibration is done on fairly on cloudless days and takes minimum 3 days.

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