Standards and Compliance

Today’s end-use electronic equipment has a number of characteristics that require protection from the electromagnetic environment. These characteristics include the growing use of digital electronics (still with a layer of analog electronics); multiple inputs and outputs for power, data, controls and indicators; ventilation for air flow and thermal management; and small openings for accessories. Few pieces of equipment use only one microprocessor. Multiple digital packages (i.e., integrated circuits) are used for small and large amounts of memory, signal processing, and input/output control just to name a few. The days of having just one power cord and a few knobs for control have long since past.

In this second installment of a two part article, we continue our review of the recent meeting of IEC-CISPR held in October 2010 in Seattle. In the first part of this article, we have described the current changes affecting the basic standard CISPR 16 and the activities of its experts within CISPR sub-committee (SC) A. We now take a look at the activities of the other CISPR sub-committees responsible for preparing the CISPR product standards. We also describe some of the projects shared by CISPR and IEC TC 77B (High Frequency Phenomena).

Perhaps the most recognized industry standard in North America for surge protectors may be UL 1449, the Standard for Safety for Surge Protective Devices ranging in applications from surge arresters (1000v ac max) to service entrance and distribution panels to plug-in surge strips. The standard was officially adopted as an ANSI standard in May 2010 and a supplement specific to the evaluation of Photovoltaic applications is expected in 2011. However, it is important to keep in mind that UL 1449 is first and foremost a safety standard. For more in-depth information regarding characterization of the surge environment, test methods and the application of these devices, the IEEE C62 standards are the definitive source in North America.

October 2010 saw the 74^th IEC General meeting in Seattle, Washington, USA. Within the IEC, its special committee CISPR (Comite International Special des Perturbations Radioelectriques –International Special Committee on Radio Interference) came together and this article reviews some of the key projects discussed at that meeting. The activities of IEC TC 77, a parallel committee to CISPR developing the IEC 61000 series and of equal importance, did not meet in Seattle and hence will not be discussed here except for the JTFs (Joint Task Forces) that exist in common with CISPR Subcommittee A, responsible for the basic standard CISPR 16, which will be the main focus of this first part of a two part article. In the second part of the article (to be published in a subsequent edition of this magazine), we will continue with the CISPR product standards and the Joint Task Forces (JTFs) existing between the different subcommittees as well as between CISPR subcommittees and IEC SC 77 B.