Design and Test of a Pre-compliance EMC Current Probe

Current probes are of paramount importance in EMC tests. Conceptually simple and of a low cost, they offer to the EMC engineer the capability to address conducted emission tests and checking on the common mode current existence, the main culprit on failures when measurements to meet emission standards is done. This paper deals with a small overview on the ferrite toroid sensor probe, its modeling, characterization on frequency domain and application in two different sectors, direct connection of balanced and unbalanced structures and on a shielded coaxial cable, two known sources of unintended common mode current.