NF FRA5022, Инструкция по эксплуатации

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4.5 Servo System Measurement
FRA5022
4-10
When enforcing operation safety measures, it is possible that for small input signal level,
noise causes dispersion in the measurement. In such cases, it is possible to maintain
measurement reliability and operation safety by splitting the frequency range and setting
the appropriate signal level for each range.
■
5055 Signal injector/probe use
When connecting directly the system under test to
FRA5022
, the influence of the
measurement cable capacitance or of
FRA5022
’ s input impedance can put the system
under test into an unstable state and its response can been seen as changing. In such
cases, it is possible to reduce the influence on the system under test by using a
separately sold
5055
Signal Injector/Probe. Details about 5055 conditions of use or
measurement are found in the
5055
Instruction Manual.
5055
can get its power supply from
FRA5022
rear panel ’ s AUX connector.
5055
comes
with 2 different FRA connection cables. Use the one that connects to the AUX
connector.
■
About handling of a floating system under test
When the system under test is not grounded, the signal ground electrical potential
varies. For it, the
FRA5022
’ s insulation voltage exceeds, common mode noise is made
and may influence the measurement. In case of doubt, use an oscilloscope to check the
signal ground electrical potential.
High frequency fluctuation can be reduced by grounding the system under test through
a bypass capacitor.
FRA5022 ’ s signal dialectic voltage is 42Vpk.
When there are risks that this range will be exceeded, ground directly or indirectly
(with the use of an appropriate impedance) the signal ground of the system under
test, and use it within this range. It is possible to use a resistor or a varistor or
any voltage controlling element as the impedance element.
！
WARNING