Instrument location : Factory, 3-phase 3-wire, 200V circuit
A transient overvoltage was detected in all events occurring several times during the measurement. Unfortunately, the cause of the transient could not be determined.
Analysis of transient waveform
- Occurred on all 3 phases (R-S, S-T, T-R) simultaneously
- Occurred twice in 1 cycle of the commercial waveform, and the interval between 2 events is 820μs
- The level is between 120V to 260V peak-to-peak
- The frequency is between 10kHz and 30kHz
Note : A threshold set at 1/2 of the waveform peak value is effective for detecting transient overvoltage. For example, set the threshold at 0.07kV for a 100Vrms circuit, and 0.14kV for a 200Vrms circuit.
Source : Guidebook for Power Quality Measurement, HIOKI E.E. Corporation