|Definition:|| situation for which the electrical equipment does not perform the intended function due to a variety of reasons, including:
- variation of a property or of a dimension of the processed material or of the work piece;
- failure of one (or more) of its component parts or services;
- external disturbances (e.g. shocks, vibration, electromagnetic interference);
- design error or deficiency (e.g. software errors);
- disturbance of its power supply;
- surrounding conditions (e.g. condensation due to temperature change).