Basics of electromagnetic compatibility (EMC)

Electromagnetic compatibility (short: EMC) describes the property of an electronic device, neither to disturb other devices by electrical or electromagnetic effects, nor to be disturbed by other devices. Seen in this way, devices with EMC are neutral to other electronic devices and systems and therefore have no effects on them that can lead to malfunctions.


Areas of application for devices with EMC

Especially in work areas with very sensitive electronic display and measuring devices, shielding possible interference is important for maintaining the function of the other systems. Conversely, EMC is also irreplaceable where electromagnetic interference is expected from the outside and a functional failure of the electronic devices must be avoided. Therefore, EMC is a property required for electrical devices in many safety-relevant areas. Below are some areas where EMC plays a particularly important role:

  • Information technology
  • Automotive sector
  • Railway technology
  • Banking systems
  • Electronics in industrial use
  • Medical technology
  • Military and avionics
  • Measuring and control engineering
  • Telecommunications
  • Entertainment technology


Measures for electromagnetic compatibility

Measures to ensure an electromagnetically compatible function in electrical equipment are essentially in the structure and design of the device. Immunity to interference and sufficiently low interference emissions must be proven in accordance with EMC guidelines and standards in order to be able to declare a product as being electromagnetic compatible. The European EMC directive defines electromagnetic compatibility as follows:

"The ability of an apparatus, machinery or system to work satisfactorily in the electromagnetic environment without causing electromagnetic interference that would be unacceptable to all apparatus, machineries or systems in this environment."

The basic protection requirements that electrical equipment must comply with are derived from this. How compatible a device must be in individual cases in order to be electromagnetically compatible depends on the later location and purpose and on which other devices work in the immediate vicinity and their electromagnetic compatibility is designed. Therefore, the shielding measures have to be adapted very individually to the requirements of the end application.


EMC in our devices

In some areas of application, particularly high demands are placed on EMC. We use a variety of ways to shield our devices so that they can be used for any special case without any problems. We do this by using different options for EMC shielding. A common and effective means is a conductive lacquer applied to the inside of the housing, which can form an electrical layer of copper, nickel, graphite or copper metallized with silver. Alternatively, the aluminum parts of the housing can also be vaporized. Both ensure effective and full-surface shielding of the keyboard's interior.

In addition, we use different EMC seals that further improve the shielding by providing critical points with additional conductive protection against electromagnetic influences. An example of a critical point of a keyboard in relation to EMC is the cable entry. In order to avoid loss of shielding attenuation, a shielded cable is used, which is connected to a circumferential EMC cable gland. It is important to ensure that the cable gland is in contact with the housing shield.


Related Links

Electromagnetic shielding (Wikipedia explanation)

Electromagnetic compatibility (Wikipedia explanation)



You have further questions on the topic or want to inquire about a project