Testing

Designers and manufacturers of electronic products are frequently faced with the question: “How do I find a high-quality EMC testing laboratory where I can confidently test my products?” The emphasis of the great majority of design and/or manufacturing entities is on obtaining (1) quality preliminary testing of EMC characteristics to refine the design of their products and (2) quality final design testing of their product for regulatory approvals. The final design, of course, is what gets manufactured and released to the general population for their use in daily life. This article is intended to aid designers and manufacturers in finding and utilizing high-quality EMC testing laboratories.

This article describes some of the everyday issues that can arise in a working EMC test laboratory which may affect the quality of the measurements made and illustrates these with real-life examples that demonstrate the importance of robust pre-test verifications. The main focus is on emissions testing, as this is perhaps the area where most problems can occur without being detected. The article also looks at how using various types of reference source during pre-test verifications can help identify those problems and prevent invalid measurements being made.

With the inventions of the transistor in 1948 and the Integrated Circuit in 1958, and the utilization of these major breakthroughs in the development of computers and other electronic devices, industry began to worry about and to design components and end-products that could survive the discharge of electrostatic discharges to chips, printed circuit boards, and final packaged-products.

"A rose by any other name would stink." – Kenneth Adamson

We have all seen advertising copy for test equipment manufacturers’ “EMC receivers” and “EMC test services” provided by commercial EMI test facilities. While we know what the aforementioned receiver does, and what sort of services the test facility supplies, the nomenclature is wrong and is symptomatic of a deeper problem.

Up until now there’s been much emphasis on designing to make a product “idiot proof”. This has provided some benefit, but what Usability Engineering is reminding us is that it is the designers who are sometimes viewed as idiots by the users. It is the users who are the experts (in usability).

FFT-based EMI test receivers can be used for EMI compliance measurements in accordance with Amendment 1 to 3rd Edition of CISPR 16-1-1 if this standard is referenced in the product standard. The use is motivated by reducing the scan time by several orders of magnitude and to get more insight due to the possibility of applying longer measurement times and enhanced measurement functions like spectrum in persistence mode. For precise and reproducible measurements the use of preselection filters is highly recommended.

This article describes the design and performance of a wide-band hybrid antenna suitable for use in reverberation chambers. The antenna is characterized over the frequency range 100 MHz to 25 GHz showing that it performs well above 200 MHz although its ultimate highest operating frequency has not been established.

An EMC test engineer’s primary responsibility includes creating test plans, procedures, analyzing test data, generating test reports, and mitigating noncompliance challenges. Many times the EMC engineer must assume the role of a software test engineer and create test programs necessary to meet the project objectives.

This year marks not only the title anniversary, but arguably also that of the beginning of the modern era in vehicle electromagnetic interference (EMI) testing. Radiated emission (RE) testing of equipment to be used on self-contained vehicles is performed at one meter or less versus testing at a distance of three meters or more for equipment designed for use in homes, offices and factories.