Line impedance stabilisation network provides compliance level measurements of conducted EMC emissions of any piece of electrical or electronic equipment
The LISN1600 from TTi (Thurlby Thandar Instruments) is a line impedance stabilisation network capable of providing compliance level measurements of conducted EMC emissions at the supply input of any piece of electrical or electronic equipment operating from a single phase AC supply.
The instrument is designed for use in conjunction with a spectrum analyser or a measurement receiver. The unit allows measurements of conducted interference, as required by CE marking regulations, to be made in-house without recourse to test-house facilities.
It has a continuous current rating of 16A, making it suitable for virtually all types of single-phase equipment.
The LISN1600 can be purchased with a variety of output connectors including IEC 16A, UK 13A and other European standard connector sockets.
The instrument fully meets the requirements of CISPR 16 for measurements in both band A (10kHz to 150kHz) and band B (150kHz to 30MHz).
A switchable 150kHz filter is incorporated to limit low-frequency signals (particularly AC line frequency) when measuring in band B.
This reduces the dynamic range requirements of the measuring device. The LISN1600 incorporates a voltage limiter to protect the vulnerable input of the measuring device against damage from power switching or interference transients.
To avoid the risk of introducing nonlinearity errors, the limiter diodes are held in reverse bias by a built-in lithium battery.
The limiter has a 10dB pre-attenuator and a switchable 10dB post-attenuator.
If required, the whole limiter/attenuator network can be switched out.
The measurement circuit can be connected to either supply line or disconnected altogether for checking the noise floor. Source selection can be remotely controlled by built-in relays where automated measurement sequences are required.
For testing hand-held apparatus which does not have an earth connection, an artificial hand connection is provided.
This conforms to the definitions in EN55014.
The LISN1600 is housed in a robust case suitable for bench or rack use measuring 132 x 212 x mm (3U half rack).
It costs £950 (plus VAT) in the UK.