Power Quality Analyzer

Analyze power quality parameters and identify potential issues per IEEE 1159.

Total Harmonic Distortion
For 3-phase systems
Short-term flicker severity

IEEE 1159 Power Quality Categories

Category Duration Magnitude
Sag0.5 cycle - 1 min0.1 - 0.9 pu
Swell0.5 cycle - 1 min1.1 - 1.8 pu
Interruption0.5 cycle - 1 min< 0.1 pu
Undervoltage> 1 min0.8 - 0.9 pu
Overvoltage> 1 min1.1 - 1.2 pu

Power Quality Limits (IEEE 519 / ANSI C84.1)

Voltage Limits

  • Service Voltage: +/- 5% nominal
  • Utilization Voltage: +/- 10% nominal
  • Voltage THD: < 5% (general)
  • Voltage THD: < 8% (individual)
  • Voltage Unbalance: < 3%

Other Limits

  • Current THD: < 5-20% (varies by Isc/IL)
  • Frequency: +/- 0.5 Hz (normal)
  • Power Factor: > 0.9 (most utilities)
  • Flicker Pst: < 1.0
  • Flicker Plt: < 0.8