Electromagnetic compatibility

ELECTRICAL appliances, machines, instruments and systems must work properly in their environment, implying that they must not only be insensitive to electromagnetic interference (EMI), but also not interfere with the working of other electrical equipment. Fitness for the electromagnetic environment is called electromagnetic compatibility (EMC). As the number of electrical products of all kinds is rising exponentially and as new electrical applications are found almost daily EMC has assumed major importance in design. Many standards for EMC have been issued, a few of the EU ones being given in Table 28.1. The standards are of three types: type A, Generic Product Standards; type B, Product Family Standards; and type C, Specific Product Standards. To find what applies to a particular product you first look for type C, then if not found, type B and if none, type A. Examples of type A are EN50081 and EN50082, of type B EN55014, EN55022 and EN55024, and of type C EN50199 and EN50263.