Water is essential for agriculture. Most of the farmers depending upon the ground water for irrigation purpose, but now a days the underground water is going to towards very deep down level. Because ...our environment affected by water drought, pollution and lack of rain falls. It will be creating negative effects to cultivation .In this present study is to assess the underground water quality in Mayiladuthurai Taluk of Nagapattinam District in Tamil Nadu. Totally 30 underground water samples were collected, which covers 10 Revenue villages in Mayiladuthurai Taluk, 3 samples from each Revenue village and analyzed all the physico - chemical parameters such as pH, EC, Ca, Na, K, SO4, Cl, Mg , CO3, and HCO3 and the water quality index SAR, RSC, Geo-chemical types, classification were determined by standard methods, standard calculation and by using standard instruments. Then the irrigation water quality results were compared with standard values Recommended by World Health Organization (WHO), Bureau of Indian Standards (BIS) and Indian Council of Medical Research (ICMR). The proposed work is very essential not only for crop production but also to maintain soil fertility, to maintain hazardous free environment and to enhance the living standard and in turn to uplift our Agriculturist.
This paper discusses about the need for conducted emission test (CE) which is a common electromagnetic compatibility (EMC) requirement for all the electronic products manufactured in military, ...civilian and automotive industries. International EMC standards in each of these industries impose CE requirement on the products to ensure their compatibility with other products which are sharing the common power source network. It is observed that the test specifications in each of these standards vary considerably. Various parameters of CE test in Mil-Std-461G, CISPR 11 and CISPR 25 standards are studied and compared to aid EMC engineers in conducting the test effectively.
EMC antennas need to be calibrated for the parameter Antenna Factor (AF). In the radiated emission measurement, Antenna Factor shall be added to the EMI receiver reading to obtain the emission level ...which will be compared with the limit lines prescribed in the EMC standards. The radiated emission (RE102) measurement as per MIL STD 461E/F/G is carried out at 1m distance. Hence the Antenna Factor at 1m distance is required to calculate the emission level. SAE ARP 958D "Electromagnetic Interference Measurement Antennas; Standard calibration method" is the standard which provides the procedures for calibration of the antennas at 1m distance.ANSI C64.5 is an another standard which provides calibration of antennas at 10m(up to 1.0GHz) and 3m (for 1GHz and above) distances. This paper analyzes SAE ARP 958D method and its associated discrepancies for the horn antenna calibration. This paper also discusses about a calibration method based on the ANSI C63.5 STD and its results obtained for the horn antenna calibration.
EMC antennas need to be calibrated for the parameter Antenna Factor (AF). In the radiated emission measurement, Antenna Factor shall be added to the EMI receiver reading to obtain the emission level ...which will be compared with the limit lines prescribed in the EMC standards. The radiated emission (RE102) measurement as per MIL STD 461E/F/G is carried out at 1m distance. Hence the Antenna Factor at 1m distance is required to calculate the emission level. SAE ARP 958D "Electromagnetic Interference Measurement Antennas; Standard calibration method" is the standard which provides the procedures for calibration of the antennas at 1m distance.ANSI C64.5 is an another standard which provides calibration of antennas at 10m(up to 1.0GHz) and 3m (for 1GHz and above) distances. This paper analyzes SAE ARP 958D method and its associated discrepancies for the horn antenna calibration. This paper also discusses about a calibration method based on the ANSI C63.5 STD and its results obtained for the horn antenna calibration.
An insight into Mil-Std-461G: A study report Chaluvadi, Mahesh; Vincentraj, G.; Thomas, K. George
2017 IEEE International Conference on Power, Control, Signals and Instrumentation Engineering (ICPCSI),
2017-Sept.
Conference Proceeding
Mil-Std-461 defines emission and susceptibility requirements for electronic, electrical and electromechanical equipment and subsystems designed or procured by agencies of Department of Defense (DoD), ...USA. Latest version of this standard, Mil-Std-461G, was released on 11 th December 2015. The same standard is used by Indian defense sector to test its equipment and subsystems for their EMC compliance. Latest version brought many changes as well as added new test requirements which are not present in earlier versions. This paper presents a study report on the latest version which discusses about new test requirements, general changes and modifications made in individual tests. The requirement of new equipment to upgrade test facility is also discussed. This study report will help test labs and engineers in upgrading test facilities as well as conducting compliance testing in accordance with latest version.
The need for review of EMC emission standard Vincentraj, G.; Subbarao, B.; Sivaramakrishnan, R.
2008 10th International Conference on Electromagnetic Interference & Compatibility,
2008-Nov.
Conference Proceeding
Generally the radiated emission measurement is performed in the frequency range of 30 MHz to 1000 MHz as per the commercial EMC standards. The conducted emission measurement is done in the frequency ...range of 150 kHz to 30 MHz. Whereas in the military standard the conducted emission measurement frequency range is from 9 kHz to 50 MHz and in the automotive standard up to 108 MHz. This paper proposes the frequency range of measurement for conducted emission from 150 kHz to 108 MHz and for radiated emission from 100 MHz to 1000 MHz. This paper also discusses the advantages of choosing the frequency band from 100 MHz to 1000 MHz for radiated emission measurement and additional issues that need to be addressed due to the change in the measurement frequency band.
Measurement of uncertainty in Electrical Fast Transient test Vincentraj, G.; Mahesh, G.; Sivaramakrishnan, R.
2006 9th International Conference on Electromagnetic Interference and Compatibility (INCEMIC 2006),
2006-Feb.
Conference Proceeding
Electrical Fast Transients (EFT) are commonly generated by relay chattering, interruption of inductive load, etc. IEC 61000-4-4 standard describes about the immunity requirements, test method / ...procedures and specifications for conducting the EFT test. The EFT test is applicable for almost all electrical / electronic products for `CE marking'. The quantification of measurement uncertainty for any EMC test including EFT test is a main concern nowadays. Standards like CISPR 16-4 explain about measurement uncertainty for Conducted Emission & Radiated Emission tests. They do not cover the conducted immunity tests. Publications like LAB 34 specify briefly about measurement uncertainty of conducted transient immunity measurement. An effort has been made in this paper to calculate and present the measurement uncertainty of EFT test on the basis of LAB 34 guidelines.
PDF
