Hioki 3196 - Voltage Dip (Instantaneous Voltage Drop) - at Distribution Panel

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CASE STUDY 6
Voltage Dip (Instantaneous Voltage Drop) - at Distribution Panel
Environment:
Problem and Analysis:
Target:
HIOKI headquarters building, East side, 5th floor
3-phase 3-wire, 200V distribution panel
4 voltage dips caused by lightning were detected during measurement (different period than Case
Study 3). The distribution panel (1-phase 3-wire) was affected by the voltage dip that occurred at
the high voltage distribution network. The table below shows the residual voltage and period of
each voltage dip. Voltage dips caused by lightning are unpreventable by the power distribution
companies. Therefore, users should take appropriate countermeasures such as connecting a UPS
to their PCs.
From June 9, 2002 to August 9, 2002Measured period:
Residual Voltage Period
1st voltage dip
2nd voltage dip
3rd voltage dip
4th voltage dip
63Vrms
47Vrms
82Vrms
56Vrms
117ms
109ms
50ms
116ms
Event Voltage Fluctuation at the 2nd Voltage Dip
Voltage and Current Waveforms at the 2nd Voltage Dip