What important that
the measuring device, connection cables and surge
protection device have the same impedance, order
to avoid excessive reflection and attenuation the
joints. The
device longer receives the full power available be-
cause the reflected power runs back along the line to
the supply source. well-matched systems, these val-
ues are around -20 systems.keep losses minimum, important verify
the cables’ transmission characteristics. Calibration also necessary that the meas-
urement results are not distorted.
Return loss
This parameter indicates how much input power
is reflected back.
Transmission characteristics can determined using
suitable measuring devices.
Incoming wave
Wave hits change impedance
Wave attenuated the joint
ZL
Impedance the incoming cable
Z0
Impedance after joint
Damped wave
Incoming wave
Wave hits change impedance
Wave partially reflected and returns
Attenuated wave
ZL
Impedance the incoming cable
Z0
Impedance after joint
Return loss
TBS
Blitzschutz-Leitfaden
2018
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en
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2020/01/10
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2020/01/10
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230
Chapter The internal lightning protection system
. the imped-
ances are different, reflections occur the joint. Key transmission
characteristics are presented below:
Insertion loss
Insertion loss describes the attenuation system
from input output. shows the transfer function of
the system and accommodates the point