NF FRA5087, Instruction Manual

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3.5 Examples of basic operations
FRA5087 3-34
WARNING
！
 Do not float the probe reference lead to 30 Vrms more than. To
avoid electric shock or failure when using probes with exposed
metal parts, do not connect the reference lead to voltages above 30
Vrms.
 In addition, the electric strength between signal terminals is dependent on the
probe used. For details, please confirm probe specification.
e) Connecting cable length and routing
The FRA5087 signal line and chassis are isolated. However, at high frequency, current can
easily flow between the cable outer conductor (shield) and ground due to stray capacitance. If
the connecting cable is long, oscillation can occur due to such properties as cable inductance and
isolation capacitance, disturbing frequency response and possibly preventing measurement.
In this type of case, such measures as shortening the cable or inserting a common mode choke in
the cable can provide improvement. For example, a clamp type ferrite core, such as used for
correcting noise, can be attached to the cable.
Cable routing and coupling between cables can change the impedance to ground and thus appear
like a variation in characteristics. In this type of case, minimizing cable junctions and securing
the cable location can improve measurement consistency.