Lisn Operation - Keysight Technologies X Series Measurement Manual

Line Impedance Stabilization Networks (LISN)

LISN Operation

LISN Operation
The following graphic shows a typical LISN circuit diagram for one side of the
line relative to earth ground. The chart represents the impedance of the DUT
port versus frequency.
The 1 μF in combination with the 50 μH inductor is the filter that isolates the
mains from the DUT. The 50 μH inductor isolates the noise generated by the
DUT from the mains. The 0.1 μF couples the noise generated by the DUT to the
EMI Receiver. At frequencies above 150 kHz, the DUT signals are presented
with a 50Ω impedance.
64 Keysight N6141A Measurement Guide