NF FRA5014, Instruction Manual

Page: 46 / 107

4.2 Servo System Measurements
FRA5014 4-4
If the injected signal level is set low to help ensure stable operations, noise may cause variation in
the measurement results. In such cases, split up the frequency range into multiple ranges and set
the optimum signal level for each range in order to achieve a balance beteen the reliability and
measurements and the stability of operations.
◼
Handling system under test when floating
When a system under test is not connected to the ground, the potential of the signal ground
fluctuates, the
FRA5014
’s dielectric insulation voltage may be exceeded or common mode noise
may occur, which can adversely affect measurements. If this is suspected, use an oscilloscope
(etc.) to check the signal ground’s potential.
Fluctuation at high frequencies can be reduced by connecting the system under test via a bypass
capacitor.
The dielectric insulation voltage of the
FRA5014
’s signals is 42 Vpk.
If it appears that this range may be exceeded, ground the system under test’s signal ground,
either directly or via an appropriate amount of impedance, to keep within this range during
use. Any voltage limiting element can be used as the impedance element, such as a resistor
or varistor.
！
WARNING