Ground Loop

I_n = Induced noise current V_n = noise voltage

V_n = I_n * R_s

• Definition : A ground circuit allowing ground currents to flow in a loop causing two problems.

1 When noise voltage is induced due to magnetic coupling, the resulting induced current causes voltages in the signal.

2 The return current may take a path further away from the signal current and create a radiating loop.

•Solution : Use a shielded cable and do not use the shield as a return conductor. (i. e. use either a twisted shielded pair or a tri axial cable.)