Overview
The purpose of a LISN is to provide the device under test with energy, to carry the interference voltage to the EMI measurement receiver and to load the RF emitted by the device under test with standardized impedance.
The NNLK 8122 is equipped with a multilayer 250 µH choke as well as with a 50 µH choke which is connected in series for each path. The multilayer choke provides an excellent decoupling between the power supply and the device under test starting at 9 kHz.
Hazard warnings
The NNLK 8122 may only be used by qualified personnel! The device under test may only be connected to or disconnected from the LISN when no voltage is applied to the LISN at all. There is a risk of fatal injury from electrical current!
Apply voltages to the LISN only after providing reliable connection to earth. Due to high capacities very high leakage currents can occur (i.e. 1.5 A at 630 VAC/50 Hz). Thus it is not possible to use a residual current operated circuit breaker. It is recommended to use an isolating transformer.
Instructions for use
Important! Connect the LISN to protecting earth BEFORE applying any voltage to it!
The device under test has to be connected to the wing terminals at the front panel. Attention! Connect or disconnect terminals only when the LISN is not energized at all!
The input for the power supply is located at the back panel and has to be connected to the corresponding wing terminals.
The coaxial RF output has to be connected to the EMI measurement receiver using a BNC coaxial cable. You can choose the path that needs to be measured with the path selection switch. The path that is actually not measured will be terminated with 50 ? automatically.
Fig. 1 Schematics NNLK 8122
Transmission EuT-Terminals to BNC | Impedance at EuT-Terminals, BNC terminated |
Frequency [MHz] | Frequency [MHz] |
Phase at EuT-Terminals, BNC terminated | Decoupling (Isolation) from Mains |
Frequency [MHz] | Frequency [MHz] |
Specifications | |
Frequency range | 9 kHz – 30 MHz |
Pre-filter choke | 250 µH |
Impedance simulation | 50 ? || (50 µH + 5 ?) |
Max. voltage | 1000 VDC 750 VAC 50/60 Hz |
Max. current | 50 A |
Weight | 22.2 kg |
Dimensions W x H x D | 450 mm x 290 mm x 550 mm |
Standard | CISPR 16-1-2 |