Electromagnetic compatibility of ISDN equipments

Electromagnetic compatibility — EMC and functional safety can no longer be treated as two separate disciplines when electrical or electronic systems are considered performing safety-related functions. Furthermore the usual EMC approach to define immunity requirements on the basis of availability and economical conditions cannot be applied to immunity issues regarding safety-related systems. And on the other hand the approach within functional safety to emphasize the relevance of the SIL cannot be transferred in a simple way into the EMC area. An appropriate approach to combine both disciplines consists of the introduction of special immunity levels and test methods in connection with a particular performance criterion “Functional Safety”.