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Field Testing & Twin SaaS
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#06Power Quality & Harmonics Survey Report

Project Framework (report reference): IEC 60364-4-41Applicable Standard: IEEE 519 / EN 50160
Module Field Guides, Standard Selection & Tutorials (3)Browse All 93+ Guides →
1 · Field Measurement ProcedureHow to Measure & Test Power Quality & Harmonics on Site: Step-by-Step Field Procedure (IEEE 519 / EN 50160)2 · Standards & Limit TablesWhich Standard Applies to Power Quality & Harmonics? Acceptance Limits, Annex Tables & Regional Equivalents (IEEE 519 / EN 50160)3 · OhmCert Tutorial & Case StudyHow to Complete a Power Quality & Harmonics Certificate in OhmCert: Worked Case Study & Troubleshooting

Multi-Asset / Multi-Point Equipment Schedule

Inspect multiple transformers, panels, rooms, motors, or RCDs in this module without overwriting previous assets. Each item receives a permanent QR Sticker UID preserved across annual audits.

Sticker UID: OC-POWE-C5F5
Plant & SLD (Auto-SLD)

Standard Limits, Equations & Space Presets

IEEE 519-2014 Table 1 (Voltage THD) & Table 2 (Current TDD by Isc/IL ratio), and EN 50160 grid quality limits for frequency, flicker Plt, and negative-sequence voltage unbalance.

One-Click Normative Presets (Auto-fills Target Limits)

Measured Inputs

Calculated / Evaluated Results

IEEE 519-2014 limits apply at the point of common coupling (PCC). The voltage THD limit follows the bus voltage level and the current limit is TDD (referred to maximum demand current IL), taken from Table 2 for the measured Isc/IL ratio.

Pending / Not tested — results stay neutral until valid measured values are entered.

  • Voltage THD at PCC

    - %

    Not tested - enter the measured value. Acceptance: THDv <= 8.0% for <= 1.0 kV (LV - 8.0% IEEE 519 / EN 50160) [IEEE 519-2014 Table 1 / EN 50160 §4.2.5]

    Pending

  • Current Distortion TDD

    - %

    Not tested - enter the measured value. Acceptance: TDD <= 5% for Isc/IL < 20 [IEEE 519-2014 Table 2]

    Pending

  • Voltage Unbalance (Negative Sequence)

    - %

    Not tested - enter the measured value. Acceptance: Negative sequence unbalance <= 2% (10 min mean, 95% of week); <= 1% at motor terminals [EN 50160 §4.2.6 / NEMA MG-1 14.36]

    Pending

  • Long Term Flicker Severity Plt

    -

    Not tested - enter the measured value. Acceptance: Plt <= 1.0 for 95% of the week [EN 50160 §4.2.3 / IEC 61000-4-15]

    Pending

  • Displacement Power Factor (cos phi)

    -

    Not tested - enter the measured value. Acceptance: 0.95 <= DPF <= 1.00 (reactive penalty threshold) [Utility Grid Code / EPDK & IEC 60364-8-1]

    Pending

  • System Frequency Stability (vs 50 Hz Nominal)

    -

    Not tested - enter the measured value. Acceptance: 50 Hz +/- 1% (49.5 - 50.5 Hz) for 99.5% of year [EN 50160 §4.2.1]

    Pending

Verification Checklist (0 / 14)

Pending

  • 1Class A power quality analyser (IEC 61000-4-30 Class A) connected at Point of Common Coupling (PCC)

  • 2Continuous 7-day logging period completed with 10-minute aggregation intervals per EN 50160 §4 / IEEE 519-2014

  • 3Rogowski coils / CT clamps verified for correct arrow orientation, range selection, and L1-L2-L3 phase matching

  • 4Voltage magnitude variations (+10% / -10% for 95% of week) and ITI/SEMI F47 voltage sag/swell events logged

  • 5Voltage Total Harmonic Distortion (THDv) and individual harmonics up to 50th order evaluated against IEEE 519 Table 1

  • 6Current Total Demand Distortion (TDD referred to peak demand IL and Isc/IL ratio) evaluated against IEEE 519 Table 2

  • 7Triplen harmonics (3rd, 9th, 15th zero-sequence) and neutral conductor thermal loading assessed

  • 8Short-term (Pst <= 1.0) and long-term (Plt <= 1.0) flicker severity verified per EN 50160 §4.2.3 / IEC 61000-4-15

  • 9Negative-sequence voltage unbalance verified <= 2.0% at PCC (and <= 1.0% at 3-phase motor terminals per NEMA MG-1)

  • 10Displacement Power Factor (cos phi) and True Power Factor (PF_true = P / S including harmonic distortion) compared

  • 11Power factor correction capacitor banks inspected for series detuning reactors (e.g., 7% / 189 Hz) to prevent parallel resonance

  • 12Active Harmonic Filter (AHF) or passive trap CT feedback loop and compensation capacity verified

  • 13Upstream transformer K-factor / harmonic loss factor (FHL) derating margin reviewed

  • 14Comprehensive PQ mitigation report (detuned banks, AHF sizing, phase balancing) issued and archived

General Notes

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Free plan: 5 of 5 inspections / calculations left this month.