The LI-550C Line Impedance Stabilization Network (LISN) provides the necessary measurement platform for performing the power line conducted emissions compliance testing as required by most worldwide standards for commercial products. The LI-550C is compliant with both CISPR 25 and CISPR 16-1-2. The LISN provides defined stable impedance and isolates the EUT from power source influences, thereby providing accurate and repeatable results. The LI-550C includes one pair of, separately housed, single-conductor networks, to be installed in series with each current-carrying conductor in a single-phase, dual-phase, or DC power system. A second LI-550C pair can be used to accommodate 3-phase power systems (Wye or Delta configurations). The LI-550C is equipped with Superior Electric SUPERCON® shrouded sockets at the mains (power input) and EUT (power output) ports. The matching color-coded plugs for connection to the mains and EUT wiring are included. This LISN uses air-core inductors to prevent saturation and permeability variation. The mounting plate of the LI-550C is left unpainted in order to facilitate connection to earth ground in its installation, which is essential due to high leakage current.