Hioki ST4030, Инструкция по эксплуатации

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Circuit Configuration
Effects of cable parasitic components
The equivalence circuit of the workpiece to be tested and the cable as seen from the output
terminal is as described below.
100 V
-
3300 V
There is parasitic capacity between the core of the coaxial cable and the shield (Ccable1, Ccable2).
Model L2250 capacity is approx. 180 pF each.
Further, there is parasitic inductance in the cable core (Lcable1, Lcable2). Model L2250 inductance
is approx. 2 µH each.
The synthetic circuit of the workpiece to be tested and the measuring cable is as described below.
100 V
-
3300 V
The inductance of the 2 cables enters the workpiece to be tested serially.
The coaxial cable shield is connected to the ground pole via the case.
The synthesis capacity of the 2 cables enters the workpiece to be tested in parallel.
During testing, impulse voltage is applied not only to the workpiece being tested but also to the
synthetic components including the cable.
The cable capacity often cannot be ignored compared to the parasitic capacity of the workpiece to
be tested, so the oscillation frequency depends greatly on the cable capacity.
For the precautions when processing the cable, see “15.10 Precautions when Processing Test
Leads” (p. 237).
15
Appendix