User manual Dual DC LISN 150 kHz – 200 MHz | Assembly of the KIT
Measurement description
The network simulation “Dual DC LISN” is used to measure the conducted
interference emissions of a test object in the frequency range of 150 kHz
up to 200 MHz. The device based on the CISPR 25 / ISO 7637 standard for
automotive electrical systems. It measures the RF interferences on both
channels of such systems by using blocking inductance of 5μH.
The measurement should do in following steps:
› DUT (device under test) and LISN placed on a conducted plane
› ISN inserted between power supply and DUT
› DUT connection should be not more than 50cm and straight above the
plane
› Connect RF output A to analyzer for measuring the dierential mode
noise from positive line or to output B to analyze the negative line
› For measuring the common mode noise additional hardware is needed
Because of strict symmetrical construction to both RF-outputs it is possible
to extract both kinds of distortion DM and CM. There is a need of passive
combiner circuits (e.g. Minicircuits ZSCJ-2-2+ (DM) and ZSC-2-2+ (CM)) to
measure this on a receiver (e.g. Spectran). Other solutions are possible. A
second solution is to use an oscilloscope with dual input and mathematics
(add, FFT). The results are similar to an EMI receiver.
Safety arrangement
In case of using this document and referred information (weblinks at the
end of this document) to build this device for own usage, please keep in
mind to save your own health.
Urgent advice:
› Read all documents.
› Follow the safety instructions and warnings.
› The device is only allowed to use for measurement applications that
are specified. Other usage is forbidden.
Essential safety instructions
1. Please only use in inside rooms. For the power supply refer to the
technical characteristics.
2. The product may only be used by authorized technical sta. The local
or country-specific safety and accident prevention regulations must be
observed for all work.
3. During operation of the product, function-related increased
electromagnetic radiation and near fields can occur. Taking into
account the increased need for protection of unborn life, pregnant
women should be protected by suitable measures. People with
pacemakers can also be at risk from electromagnetic radiation. The
influence of electronic products outside of the operational EMC
environment should be prevented by maintaining an appropriate safety
distance or by using shielded rooms.
4. Products / components must not be operated electrically, mechanically
and / or thermally beyond their intended use.
5. To ensure proper operation, no changes may be made to the device.
6. Do not use the product under conditions in which condensation could
or has occurred in or on the product, e.g. when the product has been
moved from a cold to a warm environment.
7. Please only use neutral detergents for cleaning. Never use alcohol,
benzene or thinner.
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