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INSTRUCTION MANUAL
LI-550C
LINE IMPEDANCE STABILIZATION NETWORK
19121 El T oro R d ● S il vera d o, Ca lifo rnia 926 76 ● (94 9) 459 - 9600 ● com - p ower.com
REV021317
should be bonded directly to an earth referenced ground plane for
effective RF reference ground. In cases where no ground plane is
available, a mains isolating transformer shall be used.
Please refer Safety instructions for more information on importance of
grounding. The grounding instructions are to be followed at all times.
5.3.3 EUT power port
The LI-550C has a Superior Electric Shrouded socket receptacle to power
the equipment under test. The LISN is shipped with the matching shrouded
pin plug for making the connections to EUT power cable.
5.3.4 EMI measurement Port
The LI-550C provides a
50 Ω
N-Type (female) connector to connecting the
Spectrum analyzer or EMI receiver for making conducted noise
measurements. The shielding connection of the N connector shield is
connected to the housing of the LISN and thus to ground.
Note: CISPR recommends the use of 10 dB attenuator at the output of the
LISN measurement port. Also, as the input circuitry of EMI receivers and
spectrum analyzers are extremely sensitive; it is highly recommended to use
transient limiter in line with the cable connecting the measurement port to
the measuring equipment in order to protect the input circuits from
damage by high voltage transients. Com-Power transient limiters also
incorporate both a low pass and high pass filter to attenuate out of band
signals, as well as a 10 dB attenuation pad. Both, the 10 dB attenuator and
the transient limiter are available with Com-Power.
