RTI Act
Electronics and Instrumentation Laboratory (EIL)
The electronics and instrumentation facility at NCESS campus support fabrication of equipments such as, Atmospheric Electric Field Mill, Rain Drop Charge Sensor, Air Earth Current Density Sensor and Gerdien Condenser related to atmospheric electricity measurements. The essential components are circuit designing, mechanical designing & drawing and calibration of instruments. The fibre reinforced plastic (FRP) printed circuit board for the input circuits requires special layout design since the insulation of the FRP is insufficient as the circuits are sensitive. Normal electronic layout design softwares cannot be used for designing PCBs for these input circuits. Further the very high value resistances (glass encapsulated resistances) used in these circuits are expensive and require special care. After fabrication of the input circuits along with the sensors need to be calibrated and conduct burn-in test before deployment in the field. The electronics laboratory facility thus caters to the design, fabrication, testing and calibration of extremely high sensitive input circuits at NCESS.
Rain Drop Charge Sensor
The Rain Drop Charge Sensor installed in NCESS campus. The sensor assembly is supported by six legs fastened to a triangular platform.The Rain Drop Charge Sensor is an indigenously developed instrument to measure the magnitude and polarity of electric charge in raindrop. Size and fall velocity of raindrop also can be estimated from the measurements. The sensor is mounted vertically and the rain drop is allowed to pass through the cylindrical sensor plate. Current to and fro from the sensor, due to charging and discharging process constitute current of the order of fraction of pico Ampere. This current is converted to voltage for processing and recording. It will measure the charge in drops from about 10 pC to 100 nC.
Atmospheric Electric Field Mill (EFM)
The Atmospheric Electric Field Mill is a sensor used for measuring the vertical electric field in the atmosphere. The Field Mill is designed to measure the electric field in the charged Cumulonimbus (Cb) cloud. At the time of convective precipitation, electric field measurements show high field, which ensures the presence of convective clouds. During stratiform precipitation, weak or normal values of field are exhibited. Thereby the presence of stratiform and convective clouds can be confirmed with electric field measurements. In the basic instrument, an earthed metal plate is alternately exposed to and shielded from the vertical electric field using two electrically grounded metal plates with alternately open and closed sectors of which one rotates. The instrument normally mounted at the surface with the collecting plate facing upward.