A line impedance stabilization network, also referred to as a LISN, is a device that provides quality RF impedance, stabilizes power lines, allows technicians to perform conducted emissions measurements, diverts unwanted signals from a power source, and more. LISNs are vital devices for anyone working with signal analysis and performing conducted emissions testing.
What Is Conducted Emissions Testing?
Conducted emissions testing is the type of analysis used to monitor electromagnetic signals and find any irregularities in a device or system using RF signals. This type of testing can be used on electronic devices, power lines, and other electrical equipment. Without conducted emissions testing, operators run the risk of electromagnetic interference and other problems with a network. LISNs are used to carry out conducted emissions testing and provide important information to the technicians in charge of equipment repair or maintenance.
What is a LISN?
A LISN preserves the quality of EMC measurements and blocks RF noise from returning to the power mains. A LISN uses impedance and allows operators to meet a wide range of EMC test standards, including MIL-STDs, IEC/EN, FCC, CISPR, ISO, and RTCA DO-160. In order to analyze the equipment under test (EUT), LISNs connect to a power source and the EUT. Using RF impedance, the testing can be efficiently completed at that time.
When connected to a power source, LISN sends stable impedance of 50Ω to the EUT. This filters out the typical noise and fluctuations found in a power source and allows technicians to see if the EUT is responsible for any disturbances. It is also connected to a
spectrum analyzer which visualizes the test.
LISN Applications
- Fan air cooling system
- RF noise port
- Spectrum analyzer or EMI receiver compatibility
- Large baseplate for optimal grounding
- Local and remote control
- RF shielding
- Artificial hand circuit (mimics human touch)
- Changeable pin-arrangements
- Insulated plugs for safer power connections
Note: Some of these applications will be dependent on the model and specific equipment specs.
LISN Test Standards
A LISN meets several crucial EMC test standards, including those for vehicles, boats, airborne equipment, radio frequency devices, and others. Here is the list of standards experts will be able to meet with ATEC’s selection of LISNs:
- MIL-STD 461G | Conducted Emissions
- RTCA DO-160 | Airborne Equipment
- EN 55022 | ITE Radio Disturbance Characteristics
- CISPR 16 | Radio Disturbance and Immunity
- CISPR 25 | Vehicles, Boats & Internal Combustion Engines
- FCC Part 15 | Radio Frequency Devices
- ISO 7637 | Road Vehicles: Electrical Disturbances from Conduction & Coupling
Choosing The Right LISN
ATEC offers customers affordable rental options for AC and DC LISNs from industry-leading manufacturers such as PMM, Fischer Custom Communications, and
Solar Electronics. Finding the right line impedance stabilization network can be easy when you consider the test frequency, operating voltage, and type of current your test standard calls for. Reach out to an ATEC agent to learn more about our LISNs and other conducted emissions test products. We can also help you decide on the right LISN based on your specific testing requirements.