Line Impedance Stablisation Networks (LISN)

Emissions - Laplace Instruments Ltd.

All commercial LISNs include an artificial hand connection and a transient limiter. This adds a 30dB insertion loss. A 30dB pre-amplifier is included which can be connected in the RF output feed to return the insertion loss to 0dB. All bar the heavy current LISNs are constructed in a flanged aluminium enclosure that can be bolted directly down to a ground plane (as required by standards). The underside of the enclosure is left unpainted to ensure good conductivity with the plane. The 16A and military/automotive LISNs have an RF output for each line, thus allowing parallel measurements of the emissions. This facilitates measurement of common mode and differential mode components of the emissions if required.