Keeping interference at bay

New Standard in EMC field is also available as Redline version for users’ convenience

By Morand Fachot

A SC (subcommittee) of CISPR (Special Committee on Radio Interference) has just published the second edition of an International Standard for Radio disturbance and immunity measuring apparatus. This Standard is also available in a Redline version with changes tracked.

Modern appliances, like this Dyson vacuum cleaner... (photo: Dyson Ltd)

Protecting against electromagnetic interference

Years ago, electromagnetic interference to radio or television broadcasts used to be commonplace: switching on a vacuum cleaner or a kitchen appliance often resulted in a snowy picture being displayed on TV screens or a crackling noise being heard on radio sets. It is now a far less common phenomenon, thanks to work from CISPR which works to prepare Standards in the field of EMC (electromagnetic compatibility).

 To carry out this work CISPR has 6 SCs (designated CIS/A, CIS/B, etc.) that prepare Standards in the field of EMC (electromagnetic compatibility). The Standards include:

  • radio-interference measurements and statistical methods
  • interference relating to industrial, scientific and medical radio-frequency apparatus, to other (heavy) industrial equipment, to overhead power lines, to high voltage equipment and to electric traction
  • electromagnetic disturbances related to electric/electronic equipment on vehicles and internal combustion engine powered devices
  • interference relating to household appliances tools, lighting equipment and similar pieces of apparatus
  • limits for the protection of radio services
  • EMC of information technology equipment, multimedia equipment and receivers.

Measurement is central to proper protection

The scope of CIS/A: Radio-interference measurements and statistical methods, is standardization of the following, for publication in CISPR basic EMC standards and related technical reports:

  • measuring instruments, ancillary apparatus and test sites
  • measuring methods common to several applications
  • treatment of uncertainties in CISPR compliance tests
  • sampling methods used in statistical interpretation of disturbance measurement results;

CIS/A has just published CISPR 16-1-2 ed2.0:2014, Specification for radio disturbance and immunity measuring apparatus and methods – Part 1-2: Radio disturbance and immunity measuring apparatus – Coupling devices for conducted disturbance measurements. This Standard is also available as  CISPR 16-1-2 ed2.0:2014, a Redline version that tracks changes.

Transfer of measurement method

This edition is the result of work by the JTF (Joint Task Force) A/F which was tasked with transferring the CDN (coupling/decoupling network) method of emission measurement in the frequency range 30 MHz to 300 MHz, to CISPR 16, the series of publications that covers Standards for Specification for radio disturbance and immunity measuring apparatus and methods. The goal is to apply the methods to other types of equipment.

 The CDN method was previously limited to lighting equipment in CISPR 15.

 The JTF developed specifications and measurement methods for a CDNE, the CDN for Emission measurement.

 This edition replaces the first one, which was published in November 2003. Changes concern expansion of terms, of definitions and of the abbreviations section. An annex has also been added.

Redline version for more convenience

S+ CISPR 16-1-2 ed2.0:2014, which includes both the Redline and Final versions, will prove essential for experts who need to see the changes that have been made to the previous version, who want to access the latest technical content or who want to benefit from both versions.

A Redline version is a package which includes both the new edition of a Publication and its Redline version. The Redline version clearly highlights all the changes between the new and the previous edition of a Publication by using the Track Changes functionality of Microsoft ® Word: additions and deletions are displayed in red, with deletions being struck through.

Redline versions (available in English only) provide users with a quick and easy way of comparing all the changes between standards and their previous edition.

When changes introduced in a new International Standard are as extensive, as in the case of CISPR 16-1-2 ed2.0:2014, Redline versions are most helpful as well as being highly valued by users.

dyson_dc39-multifloor Modern appliances, like this Dyson vacuum cleaner... (photo: Dyson Ltd)
tv_interference longer interfere with radio and TV transmissions thanks to CISPR Standards
emc_chamber_philips_org EMC testing chamber (Photo: Philips)