EMC - Electromagnetic Compatibility
The abbreviation EMC stands for electromagnetic compatibility and refers to the ability of technical devices themselves not to emit any intended or unintended electrical or electromagnetic pulses/effects, which in turn could influence or interfere with other technical devices. Particularly important: EMC must be ensured irrespective of the commissioning of the device. Accordingly, a machine that is switched off must not cause interference effects on another device any more than a machine that is running. Electromagnetic compatibility is also, by definition, a reciprocal characteristic. This means that EMC not only excludes active interference, but also passive interference. A technical device is therefore electromagnetically compatible if it does not influence other devices or allows itself to be influenced.
Various EMC test procedures are used to prevent intentional or unintentional interference between technical devices. This is necessary to ensure the functionality of machines in the long term and to prevent defects. In addition, the legal aspect plays a significant role: great damage can be caused by the interference of technical devices and equipment if electromagnetic compatibility is lacking. For example, electromagnetic effects can be responsible for increasing the noise level in a television set or causing the electronics of the device to fail completely. Electromagnetic waves can also be problematic in air traffic, which is why electromagnetic compatibility must be ensured. This is also the reason why in most airplanes no cell phone may be used outside the flight mode. Further examples can be found in industrial plant and mechanical engineering, where numerous different technical devices with a high output are usually in use in parallel. In order to be able to work efficiently and safely here, it is essential to ensure the EMC of the individual devices.
Legal requirements for EMC
In Germany, the Electromagnetic Compatibility Act, which was revised in 2016, applies to equipment that is either itself considered to cause electromagnetic interference or that can be affected by electromagnetic interference from other sources. With the exception of some equipment, for example aeronautical or military equipment, the law is applied across the board. The manufacturer of the respective device, or the person who places the device on the market, must ensure compliance with the EMC law. This is usually done by means of various testing and verification procedures. Various device standards, each with its own topic, are in circulation for this purpose. For example, the basic standard EN 61000-6-4:2007 + A1:2011 deals with emitted interference for industrial areas.