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4. The wiring of specimen with small capacitor
For small capacitors, when the air humidity is large, the
measured value of dielectric loss would be abnormal and unstable
as its tgδ is impacted by the surface state. At this time, the shielding
ring could be adopted for absorbing the leakage current on the
surface of the specimen. The shielding electrode is grounded when
positive connected and is connected to the shielding layer of Cx
when negative connected. This method may change the
distribution of electric field in the internal equipment under test and
then affect the tgδ. Both the standard capacitor and standard
dielectric loss tester adopt this kind of connection method.
5. The connection method of some equipment can refer to
Section IX "Reference of connection methods".
VII. Precautions
1. The instrument is only used on power-off equipment. The
grounding terminal should be connected to the grounding network
reliably.
The instrument should be used in spacious, safe and reliable
place.
2. The equipment under test is shifted to the maintenance
state if the high-voltage lead is disconnected from operation state
