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ANSI N13.30-1996, American National Standard Performance Criteria for Radiobioassay

定价： 174元 / 折扣价： 148 元

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This document describes equipment inspection and radio frequency (rf) electromagnetic field measurement procedures for evaluation of rf industrial, scientific, and medical (ISM) equipment installed in the user's facility. The term, "ISM equipment," as used here, includes equipment that generates rf energy for purposes other than radio communications, to cause physical, chemical, or biological changes; for example, industrial heaters (dielectric and induction), medical diatheremy, ultrasonic… read more equipment, rf plasma devices, and rf stabilized welders. These procedures are designed to help ensure that the equipment does not interfere with radio communications, navigation, and other essential radio services. The engineer responsible for the measurements should take all reasonable precautions to ensure that the maximum emission from the ISM equipment under test (EUT) has been measured. Radio frequency field-strength measurements of installed ISM equipment may be required if any of the following conditions exist: 1) The emission from the EUT was not measured by the manufacturer. 2) Because of its size or special operating conditions, the EUT could not be tested before installation. 3) Installed ISM equipment is suspected of causing interference. 4) ISM equipment has been modified in a way that could affect its rf emissions. 5) As the equipment ages, there is a question about its continued compliance. 6) There is a question about the safety to nearby personnel because of the emissions from the equipment. Measurements should be made under the direction of an engineer skilled in making and interpreting rf field-strength measurements. These measurements are made after the equipment is installed and ready for use at its place of use, and after it has been inspected as described in 2.2. The measurement report should generally be kept on file for at least three years after new measurements are made or after the equipment is no longer in use. There are significant differences between the "open field" or anechoic chamber measurements common in electromagnetic compatibility (EMC) and electromagnetic interference (EMI) work and the on-site measurements of installed ISM equipment. Some of these differences are described below. 1) The measurement conditions are usually more difficult because of crowded measurement locations, reflections from surrounding walls and equipment, and signals from other sources. 2 2) It is reasonable to take advantage of the shielding provided by walls and other equipment located between the ISM Equipment Under Test (EUT) and the location at which field-strength information is required. While the effect of a single wall may be small, the total effect of other equipment and building structures may be significant. In any case, it is not necessary to make measurements in a way which eliminates the benefits of this shielding. Some equipment is designed to be operated in a shielded enclosure, either because of its own sensitivity to outside interference, or because of its emission characteristics. When measuring the emission from this equipment, take advantage of the attenuation of the enclosure by making the measurements outside the enclosure, with the equipment in its normal operating position. 3) Since the measurement equipment is disconnected, moved, and reconnected many times during a set of measurements, its calibration should be checked frequently. 4) ISM equipment may often be grouped for field-strength measurements, taking one set of measurements for the entire group. 5) Electromagnetic-emission measurements of installed ISM equipment are usually significantly less accurate than laboratory (open field or test chamber) measurements because of lack of control of the measurement environment. read less

定价： 181元 / 折扣价： 154 元

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This standard provides methods for determining antenna factors (AFs) and associated parameters of antennas used to perform radiated emission measurements in electromagnetic interference (EMI) control from 9 kHz to 40 GHz. Antennas covered by this standard are linearly polarized antennas, such as loops, rods (monopoles), tuned dipoles, biconical dipoles, log-periodic dipole arrays, hybrids (i.e., combination broadband dipole and log-periodic dipole array antennas), broadband horns, etc., that… read more are used in measurements defined by various ASC C63(R) emission measurements standards (e.g., ANSI C63.4 and ANSI C63.10).4 The associated compliance measurement requirements are provided within other ASC C63(R) standards. The methods used for antenna calibration measurements include the standard site method (SSM), the reference antenna method (RAM), the equivalent capacitance substitution method (ECSM), the standard transmit loop method (STLM), the standard antenna method (SAM), and the standard field method (SFM). In 4.1, the latter three methods are included in this document by reference. read less

定价： 159元 / 折扣价： 136 元

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This part of IEC 61000 provides guidance on principles which can be used as the basis for determining the requirements for the connection of fluctuating installations to MV, HV and EHV public power systems (LV installations are covered in other IEC documents). For the purposes of this report, a fluctuating installation means an installation (which may be a load or a generator) that produces voltage flicker and / or rapid voltage changes. The primary objective is to provide guidance to system… read more operators or owners on engineering practices which will facilitate the provision of adequate service quality for all connected customers. In addressing installations, this document is not intended to replace equipment standards for emission limits. This report addresses the allocation of the capacity of the system to absorb disturbances. It does not address how to mitigate disturbances, nor does it address how the capacity of the system can be increased. Since the guidelines outlined in this report are necessarily based on certain simplifying assumptions, there is no guarantee that this approach will always provide the optimum solution for all flicker situations. The recommended approach should be used with flexibility and engineering judgment as far as engineering is concerned, when applying the given assessment procedures in full or in part. The system operator or owner is responsible for specifying requirements for the connection of fluctuating installations to the system. The fluctuating installation is to be understood as the customer's complete installation (i.e. including fluctuating and non fluctuating parts). Problems related to voltage fluctuations fall into two basic categories: * Flicker effect from light sources as a result of voltage fluctuations; * Rapid voltage changes even within the normal operational voltage tolerances are considered as a disturbing phenomenon. The report gives guidance for the coordination of the flicker emissions between different voltage levels in order to meet the compatibility levels at the point of utilisation. This report primarily focuses on controlling or limiting flicker, but a clause is included to address the limitation of rapid voltage changes. NOTE The boundaries between the various voltage levels may be different for different countries (see IEV 601-01-28) [16]. This report uses the following terms for system voltage: − low voltage (LV) refers to Un ≤ 1 kV; − medium voltage (MV) refers to 1 kV < Un ≤ 35 kV; − high voltage (HV) refers to 35 kV < Un ≤ 230 kV; − extra high voltage (EHV) refers to 230 kV < Un. In the context of this report, the function of the system is more important than its nominal voltage. For example, a HV system used for distribution may be given a "planning level" which is situated between those of MV and HV systems. read less

定价： 95元 / 折扣价： 81 元