It is common for every marketed product to contain some type of marking—label, silkscreen, engraving, stamping, or any combination of these four. Every safety standard has a section or clause that is concerned with marking. Among these markings, a label is the one that is commonly used in most products.
Considering EMC techniques during the design phase will minimize EMC problems and avoid disasters uncovered at EMC test time. At this time, the remedial measures are usually very painful.
In the typical case, where the electronic equipment is contained within a single enclosure, enclosure shielding along with cable filtering or shielding are commonly employed to meet EMC requirements.
What does “certification” mean to you? What is the value of becoming “certified?” The answer to this question has to include an answer to another question, “what is being certified?” In the electrostatic control arena, the world’s premier organization for education and standards development is the EOS/ESD Association, Inc.
China is becoming the largest consumer market in the world. Electronic equipment especially high-tech devices are most popular in China. An attractive market, yes, but are you prepared to enter this vast marketplace? Like any country in the world, China has its own regulations for electronic equipment. China Compulsory Certification (CCC) is the most widespread certification you need to overcome.
The equipment should have passed the emissions scan. It should not be susceptible to this noise. The filter analysis said this was not a problem. The case should be an excellent shield. Why doesn’t this pass?
There are two statements I have heard about electromagnetic interference which are both related and true: EMC is the science and engineering of things that are typically not on the schematic [1], and EMI is often caused by issues of geometry [2]. The first statement speaks to the issues of parasitics, or cross coupling of energy due to magnetic induction or capacitance. The second says that the parasitics can be controlled or reduced if the proper routings and separations are maintained, and that once a degree of understanding about these coupling mechanisms is understood the control of them can be obtained.
When we think of grounding systems, we tend to think only of resistance and how resistance can be reduced. But the things we do to lower resistance may increase inductance, which could actually make matters worse, especially for fast-rising secondary surges.
When calibrated test equipment is found in an out-of-tolerance condition, there is additional risk to all products on which it was used. It is important to understand the magnitude of the potential risk because it can lead to dangerous consumer situations and additional business costs.