Document Type:Technical Results
This Product is publicly available
Concomitant with the widespread deployment of Advanced Metering Infrastructure (AMI) is the need to characterize radio-frequency (RF) emissions from wireless smart meters. A previous EPRI Technical Report (1021126) provided a detailed characterization of RF emissions from one type of wireless smart meter deployed across several service territories in the U.S. This report describes emissions from wireless smart meters produced by two manufacturers that are currently in operation within a large service territory in the U.S.
ObjectiveCharacterizing RF emissions from wireless smart meters requires an intimate knowledge of the principles upon which a particular system operates. For example, the smart meters studied cannot be configured to operate continuously under any practical conditions in the field. Thus, a method was introduced under controlled conditions to "ping" the meters so as to obtain a reliable data stream of emissions. This technique was used for measurements within residences, but in the case of apartment structures, the normal, ambient emissions were measured without deliberately "pinging" of the meters.
ApproachThe investigator conducted measurements of the RF emissions of the various models of wireless smart meters distributed throughout the service territory's customer base. To accomplish this objective cooperation was obtained from both the vendor and the utility. Measurements were conducted under controlled conditions with individual units isolated from any sources of spurious fields. Measurements were also conducted to characterize field levels both within and outside of residences. Additionally, estimates were made of the operational duty cycle range of the system based on data the vendor provided to the investigator.
ResultsThe RF field levels from the smart meters studied are below the exposure limits stipulated by the Federal Communications Commission (FCC). Furthermore, data from the meter provider permits one to estimate that, as the system currently operates, nearly 99.9% of the meters transmit 1% or less of the time, and 99% of the meters transmit less than four-tenths of one percent of the time. These duty cycles are taken into account when estimating potential exposures of people in relation to FCC exposure limits for the general public, which are based on a 30-minute average of power density across the body.
Application, Value and UseThe data in this report add to an accumulating body of knowledge concerning the operation of wireless smart meters and the RF emissions associated with their use. This information has value insofar as responding to questions from agencies, such as Public Utility/Service Commissions, as well as to the interested public and scientific community.
EPRI PerspectiveMeasuring electric energy consumption with smart meters in residential and commercial environments is becoming more commonplace as part of the development of Advanced Metering Infrastructure (AMI) in the electric utility industry. With the deployment of wireless smart meters, public concern has been raised about potential health effects associated with their RF emissions. EPRI is responding to these concerns with research efforts to provide objective information on RF emissions related to smart meters.
For further information about EPRI, call the EPRI Customer Assistance Center at (800) 313-3774 or email email@example.com