EMI (Electromagnetic Interference), EMS (Electromagnetic Susceptibility) and EMC (Electromagnetic Compatibility) are the main concepts related to electromagnetic fields. So what’s the difference between EMI vs EMS vs EMC? Keep reading!
What is EMI?
EMI (electromagnetic interference): refers to the phenomenon in electronic equipment or systems that electromagnetic energy in a certain power supply, signal line, transmission line or space has a negative impact on other electronic equipment or systems. EMI includes radiated electromagnetic interference (transmitted through electromagnetic wave radiation) and conducted electromagnetic interference (transmitted through wires or contact media).
EMI principle: When the current and signal in an electronic device or system are transmitted on wires, circuit boards, etc., an electromagnetic field will be generated. These electromagnetic fields can affect other devices or systems through radiation or conduction, thereby causing electromagnetic interference. Radiated electromagnetic interference refers to the propagation of electromagnetic waves through space, while conducted electromagnetic interference refers to the transmission of electromagnetic energy through wires or contact media.
What is EMS?
EMS (Electromagnetic Immunity): Also known as anti-interference ability, it refers to the ability of electronic equipment or systems to work normally in an environment with electromagnetic interference. EMS measures the resistance of a device or system to external electromagnetic interference, and a higher EMS means that the device has better anti-interference performance.
EMS principle: EMS refers to the resistance of equipment to electromagnetic interference. The principle is to reduce the sensitivity to external electromagnetic interference by designing and adopting appropriate electromagnetic shielding measures. This includes the use of electromagnetic shielding materials, optimized circuit layout, ground planning, and grounding design to reduce the effects of electromagnetic interference. In addition, filters, isolators, and protection devices can be used to improve the electromagnetic immunity of the equipment.
What is EMC?
EMC (Electromagnetic Compatibility): refers to the ability of different electronic devices or systems to work together without interfering with each other. It ensures that devices can work properly simultaneously in a specific environment without interfering with each other or being affected by external electromagnetic interference. EMC considers the issues of electromagnetic radiation and conduction and takes measures to ensure compatibility between devices.
EMC principle: EMC aims to ensure that different devices or systems will not interfere with each other when they work together. The key to realizing EMC is to reduce the interference sources of electromagnetic radiation and conduction, and optimize the design to maximize the electromagnetic compatibility between devices. This includes electromagnetic compatibility testing and verification of products, following international and industry standards, while taking appropriate isolation, filtering, shielding and other measures to manage electromagnetic interference and improve anti-interference capabilities.
Methods to deal with EMI/EMC problems
1. Design and layout: During the design process of electronic devices, EMI/EMC factors should be considered, and appropriate circuit layout and wiring harness wiring methods should be used to reduce electromagnetic radiation and induction. For example, reduce the radiation interference by reducing the loop area and shortening the length of the wire.
2. Shielding and Isolation: Use appropriate shielding materials and techniques to limit electromagnetic radiation and induction. Shielding can confine electromagnetic fields within the device and prevent them from spreading to the surrounding environment.
3. Filter: Adding appropriate filters to the input and output circuits can effectively reduce the spread of high-frequency interference. Filters can prevent unwanted harmonics and high-frequency signals from entering the power line or output line.
4. Grounding and connection: Reasonable grounding and connection methods can reduce common mode noise and ground return flow, and help improve the EMC performance of the system.
5. EMC testing and certification: EMC testing should begin at the early stages of product development to identify and resolve potential interference issues. At the same time, ensure that the product complies with relevant EMC certification standards to ensure that it is sold compliantly in the market.
6. Electromagnetic compatibility training: Training engineers and designers to understand EMI/EMC issues, standards and solutions will help to better handle related issues during the design stage.
Conclusion
To sum up, EMI refers to the phenomenon of electromagnetic interference, EMS refers to the resistance of equipment to electromagnetic interference, and EMC is the ability to ensure that equipment is compatible with each other and works normally in a common environment. The goal of EMC is to ensure that electronic equipment can work harmoniously in the electromagnetic environment through optimized design, testing and verification, while avoiding interference with other equipment and systems.
EMI (electromagnetic interference): refers to the phenomenon in electronic equipment or systems that electromagnetic energy in a certain power supply, signal line, transmission line or space has a negative impact on other electronic equipment or systems. EMI includes radiated electromagnetic interference (transmitted through electromagnetic wave radiation) and conducted electromagnetic interference (transmitted through wires or contact media).
EMS (Electromagnetic Immunity): Also known as anti-interference ability, it refers to the ability of electronic equipment or systems to work normally in an environment with electromagnetic interference. EMS measures the resistance of a device or system to external electromagnetic interference, and a higher EMS means that the device has better anti-interference performance.
EMC (Electromagnetic Compatibility): refers to the ability of different electronic devices or systems to work together without interfering with each other. It ensures that devices can work properly simultaneously in a specific environment without interfering with each other or being affected by external electromagnetic interference. EMC considers the issues of electromagnetic radiation and conduction and takes measures to ensure compatibility between devices.
Author
Kerstin
Hi, I am Kerstin, graduating from one of a well- known university in China and I has a master's degree in physics. I have more than 5 year's experience as a professional engineer in PCB industry and expertise in PCB design, PCB assembly, PCB manufacturing, etc. I am committed to offering services and solutions about PCB/PCBA for various industries for their projects with professional knowledge. During 5 years of engineering career, I have done different circuit designing projects for different companies such as electronics, industry and medical devices, winning a lot of reputation among many customers. Selected as an outstanding employee of IBE every year. I'm always here to provide you with fast, reliable, quality services about PCB/PCBA.