ELECTROMAGNETIC COMPATIBILITY Electromagcompat1.doc ELECTROMAGNETIC COMPATIBILITY February 2002 REMINDERS DIFFERENTIAL MODE DM signal transmission (to and from isolated wires) DM disturbance : if two wires are close to each other but far from a disturbance source , DM disturbance may be neglected . DM measurement COMMON MODE CM signal transmission (the return signals flow on a common conductive path) CM disturbance : the disturbance is shared by every conductor in the same direction and the total return takes place in the ground The ground is a dustbin for Icm ……