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New Requirements in International EMC StandardsA flurry of changes to some international electromagnetic compatibility (EMC) standards have been officially published in the last several months. These EMC standards include both emission and immunity requirements. Typically, these international EMC standards are adopted by various countries and economic regions worldwide, and they become part of the regulatory environment that electronic products must cope with in their product life. Emissions CISPR 11, Edition 4.0. Industrial, Scientific and Medical (ISM) Radio-Frequency Equipment—Electromagnetic Disturbance Characteristics—Limits and Methods of Measurement. This new edition changed quite a few areas in the document. It added four definitions: electrodischarge machining (EDM) equipment, spark erosion, arc welding equipment, and arc welding. It added emissions limits for EDM and arc welding equipment, including a new table 5b for radiation disturbance limits for Class A EDM and arc welding equipment measured on a test site. Edition 4.0 also added a new subclause 7.3 on alternative radiation test sites for the frequency range of 30 MHz to 1 GHz. CISPR 13, Edition 4.1. Limits and Methods of Measurement of Radio Interference Characteristics of Sound and Television Broadcast Receivers and Associated Equipment. This consolidated edition was released in March 2003 and combined Amendment 1 and Edition 4.0. CISPR 14-1, Consolidated, Edition 4.2. EMC—Requirements for Household Appliances, Electric Tools, and Similar Apparatus—Part 1: Emission. This edition added some new wording to paragraph 5.2.3 concerning terminal voltage on nonrewirable leads. It now states, "The measurement of the terminal voltage on non-rewirable leads longer than 2 meters and shorter than 10 meters shall be started at a frequency according to the following formula: F (start) = 60 / L where L is the length of the connecting lead between the appliance and the auxiliary apparatus, in meters." This amendment also added new text to paragraph 7.3.1 (motor-operated appliances for household and similar purposes). Smaller changes were made to clauses 7.3.7.3.1, 7.3.7.3.2, 7.3.7.4, and 7.4.2.2. CISPR 15, Consolidated, Edition 6.2. Limits and Methods of Measurement of Radio Disturbance Characteristics of Electrical Lighting and Similar Equipment. This edition replaced the existing paragraph in 5.9.3 (measurement in emergency mode, i.e., operating condition after disruption of the mains supply) with the following: "Luminaires which supply the lamp(s) with a current having an operation frequency in excess of 100 Hz while in the emergency mode shall comply with the disturbance voltage limits at mains terminals given in table 2a and the radiated electromagnetic disturbance limits given in table 3." CISPR 16-1, Consolidated, Edition 2.1. Specification for Radio Disturbance and Immunity Measuring Apparatus and Methods—Part 1: Radio Disturbance and Immunity Measuring Apparatus. This edition added a new subclause, 4.3.4.3, entitled "Response to intermittent, unsteady, and drifting narrowband disturbances." This subclause included two new figures (60 and 61). It also included table 21, "Maximum reading of average-measuring receivers for a pulse-modulated sine-wave input in comparison with the response to a continuous sine-wave having the same amplitude." The edition also added a new paragraph in subclause 5.5.3.1 (electric antenna). The new paragraph states, "Information pertaining to calculating the performance characteristics of a 1-meter length monopole (rod) antenna and the characterization of its matching network is specified in Annex X." Annex X, a normative annex, was added with the required details to calculate the performance. CISPR 16-2, Consolidated, Edition 1.2. Specification for Radio Disturbance and Immunity Measuring Apparatus and Methods—Part 2: Methods of Measurement of Disturbances and Immunity. For this edition, a new Annex E was added to the base document. It is an informative annex, titled "Measurement of Disturbances in the Presence of Ambient Emissions." The new edition also added significant information in clause 2.6.5 (measurements of in situ equipment), including:
CISPR
16-3, Consolidated, Edition 1.1. Specification for Radio Disturbance
and Immunity Measuring Apparatus and Methods—Part 3: Reports
and Recommendations of CISPR. This edition of CISPR 16-3
combines Edition 1:2000 with Amendment 1:2002 and was released
in August 2002. Amendment 1 added a new clause 6 entitled, "Reports
on Uncertainties in Standardized Emission Compliance Testing."
The primary goal of this clause is to give guidance to those
who are involved in the development or modification of CISPR
emissions standards. In addition, the clause is useful background
information for those who apply the standards in practice.
According to CISPR, this edition contains recommendations on statistics of disturbance complaints, on the significance of CISPR limits, on determination of CISPR limits, and on other specific reports that were previously published in CISPR 7 and CISPR 8. CISPR 16-4, Edition 1.0. Specification for Radio Disturbance and Immunity Measuring Apparatus and Methods—Part 4: Uncertainty in EMC Measurements. This premier edition was released in May 2002. It reviews three cases of measurement uncertainty in EMC: conducted disturbance (9 kHz to 30 MHz), disturbance power (30 to 300 MHz), and radiated disturbance of electric field strength (30 MHz to 1 GHz). Peter Kerry, CISPR chairman, presented an overview of this new standard shortly after its release.1 CISPR 22, Edition 4.0. Information Technology Equipment—Radio Disturbance Characteristics—Limits and Methods of Measurement. This edition was released in April 2003 and replaces Edition 3.0. The standard was prepared by CISPR Subcommittee 1: EMC of Information Technology Equipment, Multimedia Equipment, and Receivers. CISPR 25, Edition 2.0. Radio Disturbance Characteristics for the Protection of Receivers Used on Board Vehicles, Boats, and on Devices. This edition was published in August 2002. This standard is designed to protect receivers from disturbances produced by conducted and radiated emissions arising in a vehicle. Test procedures and limits given are intended to provide provisional control of vehicle-radiated emissions, as well as component, module conductor, radiated emissions of long and short duration. The standard:
Immunity IEC 61000-4-3, Consolidated, Edition 2.1. Part 4-3. Testing and Measurement Techniques—Radiated, Radio-Frequency, Electromagnetic Field Immunity Test. This edition changes the base document (which was just released in March 2002) by making a major change to clause 6.2—Calibration of Field. It does this by adding two new subclauses: 6.2.1 (constant field strength calibration method) and 6.2.2 (constant power calibration method). In addition, the new edition changes the dwell time concept by adding the following words to the standard: "The dwell time of the amplitude modulated carrier at each frequency shall not be less than the time necessary for the [equipment under test] EUT to be exercised and to respond but shall in no case be less than 0.5 seconds." Finally, it adds a new informative annex, Annex K, "Amplifier Non-Linearity and Example of the Calibration Procedure According to 6.2." IEC 61000-4-7, Edition 2.0, Part 4-7. Testing and Measurement Techniques—General Guide on Harmonics and Interharmonics Measurements and Instrumentation, for Power Supply Systems and Equipment Connected Thereto. This standard is applicable to instrumentation intended for measuring spectral components in the frequency range up to 9 kHz that are superimposed on the fundamental of the power-supply systems at 50 and 60 kHz. The standard defines the measurement instrumentation intended for testing individual items of equipment in accordance with emissions limits given in certain standards (e.g., harmonic current limits as given in IEC 61000-3-2). It also defines instrumentation for testing the measurement of harmonic currents and voltages in actual supply systems. The instrumentation for measurements above the harmonic frequency range (up to 9 kHz) is tentatively defined. The second edition cancels and replaces the first edition (published in 1991) and constitutes a technical revision. IEC 61000-4-16, Edition 1.1. Part 4-16. Testing and Measurement Techniques—Test for Immunity to Conducted, Common-Mode Disturbances in the Frequency Range 0 Hz to 150 kHz. This standard was released in July 2002. It consolidates Edition 1:1998 with Amendment 1:2001. It includes a key subclause (8.1.1) on climatic conditions that was added in Amendment 1. The subclause states, "Unless otherwise specified by the committee responsible for the generic or product standard, the climatic conditions in the laboratory shall be within any limits specified for the operation of the EUT and the test equipment by their respective manufacturers. Tests shall not be performed if the relative humidity is so high as to cause condensation in the EUT or the test equipment." Amendment 1 also added two new clauses: clause 9, Evaluation of Test Results and clause 10, Test Report. IEC 61000-4-20, Edition 1.0, Part 4-20. Testing and Measurement Techniques—Emission and Immunity Testing in Transverse Electromagnetic (TEM) Waveguides. This edition was released in February 2003. It is the first international standard on TEM test facilities. Product Family Standard IEC 61326, Edition 1.0. Electrical Equipment for Measurement, Control and Laboratory Use—EMC Requirements. This product family standard was released in February 2002. It cancels and replaces the first edition of IEC 61326-1 (published in 1997), Amendment 1 (1998), and Amendment 2 (2000). The new edition constitutes a technical revision of IEC 61326-1. In addition, a Corrigendum 1 was released in July 2002. The corrigendum corrected the edition number and eliminated definition 3.12 (performance criteria A). It also modified a performance criterion for electromagnetic fields in Annex E of the standard. Conclusion IECInternational standards in the area of EMC engineering are living documents. They change on a regular basis as new information becomes available based on the usage of the standard and research and development work done around the world. The latest versions of the international standards, amendments, and corrigenda are available electronically by accessing the International Electrotechnical Commission Web site at http://www.iec.ch. Reference 1. "First IEC International Standard on EMC Measurement Uncertainty," Compliance Engineering 19, no. 5 (2002): 1618. Daniel D. Hoolihan is president of Hoolihan EMC Consulting (Lindstrom, MN). He can be reached at hoolihan@emcxpert.com.
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