Electromagnetic compatibility (EMC) is one of the top considerations when designing any electronic device. With good EMC, you can keep your device from emitting and receiving signals that can interrupt functionality. EMC is also a crucial part of meeting different organizations' and governments' standards and requirements. Not meeting these standards can prevent you from selling your product in significant markets.
Complicating the process involves varying standards for different types of devices. Industrial washers differ from consumer washers, which differ from kitchen blenders. Let's look at what you need to know about designing consumer and commercial appliances for EMC specifications.
Every electronic device creates electromagnetic noise, and designing for EMC is about controlling that noise. With a range of technologies and design strategies, designers must prevent their electronics from releasing this interference and affecting the functionality of other devices. In turn, every device should be protected from interference. This system of compatibility ensures our electronics can coexist and work properly.
The level of EMC required can vary widely. If a coffee maker stops working, the repercussions likely aren't very drastic. On the other hand, an operating room's equipment must always stay functional. The standards for medical equipment are understandably more strict than those for consumer devices. The same thinking applies when comparing household appliances, consumer-grade electronics, and industrial-level equipment.
Standards will also vary by the regulating body. Some of the organizations that establish standards for EMC include:
Thankfully, many of these groups turn to international standards to determine requirements, so designers can often focus on a few standards that apply to multiple regions, making worldwide sales easier. Some popular international standards come from the Comité International Spécial des Perturbations Radioélectriques (CISPR), the International Electrotechnical Commission (IEC), and the International Organization for Standardization (ISO). You'll also see European Standards used, abbreviated as EN from the German term "Europäische Norm." Lastly, the popular UL marking comes from an international group, UL Solutions.
Designers employ different techniques to achieve EMC, such as specific board layouts, filters, circuit partitioning, grounding, and shields. These strategies can stop electromagnetic noise and prevent it from causing compatibility issues in several ways. For instance, a filter works well on low-frequency lines, while shields are most effective at high frequencies. The right strategies vary widely by device and applicable standards.
Small household appliances are often near other electronics, including more extensive and smaller devices. Some examples include:
EMC design guidelines for these devices include the following:
Designing appliances for EMC standards often requires meeting guidelines for large pieces of equipment. White goods refer to larger appliances like:
These devices also fall under COneSPR 14-1 and 14-2. IEC 61000 includes sections covering white goods, including Parts 4-2, 4-4, 4-5 and 4-6. These parts outline requirements for electrostatic discharge immunity, burst/electrical fast transient immunity, surge immunity, and immunity to radio frequency-induced conducted disturbances.
Commercial appliances are used in industrial or commercial settings. Some examples include the following:
Many of these devices fall under specific standards for that type of equipment. For example, UL 621 offers a standard for ice cream makers, while UL 471 covers commercial refrigerators and freezers. The EMC Directive from the EU also applies to commercial appliances.
Here are some standards to consider for different types of devices:
Of course, this list is not exhaustive, and many commercial appliances fall under their standards.
Meeting regional or global standards for electrical equipment can be complex. The right components and some expert support make it easier. At Astrodyne TDI, we have both. We offer a wide range of power supplies and EMC filters to help you meet or exceed applicable product standards.
Reliable equipment can help you pass certification tests with flying colors and ensure your products' continued safety and positive reputation. We build components for some of the strictest industries, including military and medical equipment, so we know how to meet unique design specifications.
Explore our off-the-shelf power supplies and filters online! If you need custom components or aren't sure what you need, please contact our knowledgeable team for more information!