The LI-3P-4x Series consists of four separate models of four-conductor, 50Ω, 50 μH Line Impedance Stabilization Networks (LISNs). The primary differences between the four models are their respective current ratings:
LI-3P-416 16 Amps (per line, continuous)
LI-3P-432 32 Amps (per line, continuous)
LI-3P-463 63 Amps (per line, continuous)
LI-3P-4100 100 Amps (per line, continuous)
These LISNs provide the necessary measurement platform for performing power line conducted emissions compliance testing per MIL-STD-461, CE102, conducted emissions, radio frequency potential, power leads. The LISNs perform the following functions:
• provide a defined, stable power line impedance across its frequency range for the Equipment Under Test (EUT);
• isolate the EUT and measurement circuit from the power source, thereby minimizing its influence on the measurements; and,
• couple the disturbance voltages to the coaxial measurement port, which connects to the measuring instrument.
The LISNs use air-core inductors to prevent saturation and permeability variation. The mounting plates are left unpainted in order to facilitate connection to earth ground in their installation, which is essential due to high leakage currents.
The side panels for each LISN are louvered for cooling purposes. The LI-3P-463 and LI-3P-4100 also include two internal cooling fans operated by a switch on the rear panel.