Aspects of the bulk current immunity test

Susceptibility measurements pose extreme problems when the vehicle of interest is physically large as the case of aircraft. It is usually impractical to subject the equipment under test (EUT) to very high level electromagnetic fields in the open, in its operational mode. It is generally equally impractical to find a suitable enclosure within which well-conditioned high-level fields can be generated. A method currently being used to overcome this problem in the aircraft industry and elsewhere has been called bulk current injection. This involves injecting current into groups of cables entering ports of a selected part of the system being tested. This injection is carried out using a suitable form of magnetic coupling, between the signal source and the cable harnesses