712013 IEEE Electromagnetic Compatibility Magazine Volume 2 Quarter 4
L. Premalatha received the Ph.D. in Elec-trical Engineering from Anna University, India. She is currently working as a Pro-fessor at the Anand Institute of Higher Technology, Chennai, India. She has more than 15 years of teaching experience. She has presented her research papers in var-ious journals and conferences. Her research interests include power elec-tronics and drives, nonlinear dynamics
and control and electromagnetic compatibility.
T. A. Raghavendiran obtained his doc-torate from Anna University in 2004. He has more than 18 years of experience in teaching and nine years of experience in industry. He has presented more than 15 research papers in various journals, national and international conferences and has executed a number of projects sponsored by national agencies. He is currently serving as Principal at the
Anand Institute of Higher Technology, Chennai, India. His areas of interest include power electronics, energy systems and power quality.
COMAR Finding on Radiofrequency Safety and Utility Smart MetersBy Daniel D. Hoolihan, Designated Liaison between COMAR and the IEEE EMC Society
COMAR is an abbreviation for Committee on Man and Radiation. COMAR is a committee operating under the umbrella of the Engineering in Medicine and Biology Society (EMBS) of the Institute of Electrical and Electronics Engineers (IEEE). The Com-mittee writes Technical Information Statements (TISs) from time to time about topics concerning the safety of exposure to radio frequency (RF) energy.
The topic of the present TIS is Radiofrequency Safety and Utility Smart Meters. The TIS describes the Smart Meter technology being used by modern electric power metering systems and the levels of RF emissions from the meters. It compares the emanations from the Smart Meters to United States and International RF Safety Limits and it also compares the emitted levels to RF signal levels from other sources.
The TIS concludes that The low peak power of Smart Meters and the very low duty cycles lead to the fact that accessible RF fields near Smart Meters are far below both United States and International RF Safety Limits whether judged on the basis of instantaneous peak power densities or time-averaged exposures.
Following is the abstract of the TIS. To view the entire document on line, visit: http://www.emcs.org/committees/sc01/index.html.
This Technical Information Statement describes Smart Meter technology as used with modern electric power metering sys-tems and focuses on the radio frequency (RF) emissions associatedwith their operation relative to human RF exposure limits. Smart Meters typically employ lowpower (~1 W or less) transmitters that wirelessly send electric energy usage data to the utilitycompany several times per day in the form of brief, pulsed emissions in the unlicensed frequencybands of 902-928 MHz and 2.4-2.48 GHz or on other nearby frequencies. Most Smart Metersoperate as wireless mesh networks where each Smart Meter can communicate with otherneighboring meters to relay data to a data collection point in the region. This communica-tionprocess includes RF emissions from Smart Meters representing energy usage as well as therelaying of data from other meters and emissions associated with maintaining the metershierarchy within the wireless network. As a consequence, most Smart Meters emit RF pulsesthroughout the day, more at certain times and less at others. However, the duty cycle associated-with all of these emissions is very small, typically less than 1%, and most of the time far lessthan 1%, meaning that most Smart Meters actually transmit RF fields for only a few minutes perday at most. The low peak power of Smart Meters and the very low duty cycles lead to the factthat accessible RF fields near Smart Meters are far below both U.S. and international RF safe-tylimits whether judged on the basis of instantaneous peak power densities or time-averaged exposures. This conclusion holds for Smart Meters alone or installed in large banks of meters.
NOTE: The IEEE EMC Society has a special committee - SC1 - that is a repository for Smart Grid information. This COMAR report is on its web site.