One of the most frequent questions engineers ask before inspecting Power Quality & Harmonics Survey Report is: "Which standard should I cite on the certificate, and where do the pass/fail limits come from?" This reference guide maps IEEE 519 / EN 50160 to national regulatory adoptions and provides the complete standard annex tables.
1. National & Regional Standard Equivalence Matrix
| Region / Language | Adopted National Standard & Regulatory Code |
|---|---|
| International / UK (EN) | IEEE 519 / EN 50160 |
| Turkey (TR · Türkçe) | TS EN 50160 / IEEE 519-2014 / EPDK Şebeke Yön. |
| Germany / DACH (DE · Deutsch) | DIN EN 50160 / IEEE 519-2014 / VDE-AR-N 4100 |
| France (FR · Français) | NF EN 50160 / IEEE 519-2014 |
| Spain (ES · Español) | UNE-EN 50160 / IEEE 519-2014 |
| Italy (IT · Italiano) | CEI EN 50160 / IEEE 519-2014 |
| Gulf / Middle East (AR · العربية) | IEEE 519 / EN 50160 / SASO / DEWA / ADDC |
2. Normative Acceptance Criteria & Mathematical Basis
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.
TDD: TDD = sqrt(sum(I_h^2)) / I_L x 100% — Total Demand Distortion referenced to maximum 15/30-min demand load current I_L at PCC (IEEE 519-2014).
V_unbalance: u2 = (V_neg / V_pos) x 100% <= 2.0% — Negative-sequence voltage unbalance factor per EN 50160 §4.2.6 (<= 1.0% recommended at 3-phase motors per NEMA MG-1).
3. Official Standard Reference Tables
IEEE 519-2014 Table 1 & Table 2: Harmonic Voltage (THDv) & Current (TDD) Limits at PCC (IEEE Std 519-2014)
| Parameter / Short-Circuit Ratio | Condition / Bus Voltage | Individual Harmonic Limit | Total Distortion Limit (THDv / TDD) |
|---|---|---|---|
| Bus Voltage V <= 1.0 kV | General LV PCC (IEEE 519-2014 / EN 50160) | 5.0% | THDv <= 8.0% |
| Bus Voltage 1 kV < V <= 69 kV | MV Distribution PCC | 3.0% | THDv <= 5.0% |
| Bus Voltage 69 kV < V <= 161 kV | Sub-transmission PCC | 1.5% | THDv <= 2.5% |
| Current Ratio Isc / IL < 20 | Weak grid / dedicated transformer | h<11: 4.0% | 11<=h<17: 2.0% | TDD <= 5.0% |
| Current Ratio 20 <= Isc / IL < 50 | Typical industrial PCC | h<11: 7.0% | 11<=h<17: 3.5% | TDD <= 8.0% |
| Current Ratio 50 <= Isc / IL < 100 | Stiff distribution PCC | h<11: 10.0% | 11<=h<17: 4.5% | TDD <= 12.0% |
| Current Ratio 100 <= Isc / IL < 1000 | High fault level substation | h<11: 12.0% | 11<=h<17: 5.5% | TDD <= 15.0% |
| Current Ratio Isc / IL >= 1000 | Very stiff utility bus | h<11: 15.0% | 11<=h<17: 7.0% | TDD <= 20.0% |