⚡ Testing of harmonic current emissions of electrical and electronic equipment with rated input current above 16 A up to 75 A per phase connected to public low-voltage systems (limits of this edition for 230/400 V, 50 Hz) — reference current Iref (average r.m.s. current, manufacturer’s value within ±10 %), measurement of each harmonic in DFT windows with 1,5 s smoothing according to IEC 61000-4-7 and averaging over the observation period, each smoothed value up to 150 % of the limit, THC and PWHC disregarding harmonics below 1 % of Iref, limits depending on the short-circuit ratio Rsce; type test or validated simulation, PN-EN 61000-3-12

Electronics and EMC PN-EN 61000-3-12

Overview

WHAT THE STANDARD COVERS. The PKN catalogue card of PN-EN 61000-3-12:2012 (English version) has no scope field in Polish — it gives the title, the introduction of EN 61000-3-12:2011 and IEC 61000-3-12:2011 [IDT], Directive 2014/30/EU and the additional element PN-EN 61000-3-12:2012/A1:2024-11. We read the text in two samples: IEC 61000-3-12:2011 (edition 2.0) from the cover to the beginning of 4.3 (equipment consisting of several self-contained items) and IEC 61000-3-12 edition 2.1 (2021-06, consolidated version: edition 2.0, interpretation sheet 1 of 2012 and amendment 1 of 2021) — redline version, from the cover to the end of definition 3.14. We do not have Clauses 4.3–7 (requirements and limits with Tables 2–5, product documentation, test and simulation conditions) or Annexes A (normative — type test conditions), B and C — we know only their titles from the table of contents. We know Clause 4 from edition 2.0; whether amendment 1 changed this clause we do not know, because the edition 2.1 sample ends at Clause 3.

ACCORDING TO THE TEXT OF IEC 61000-3-12 (edition 2.0: foreword, introduction, Clauses 1–4.2.7; edition 2.1: foreword, interpretation sheet, Clauses 1–3, table of contents). The standard was prepared by subcommittee SC 77A of IEC TC 77; it is a product family standard. Edition 2.0 is a technical revision: the fundamental current I1 was replaced by the reference current Iref for the calculation of limits, Table 5 of limits was added, Annex A with test conditions for some types of equipment was added, the former Annexes B (approximate interpolation formulas) and D (PWHD factor) were deleted. Interpretation sheet 1 (September 2012): when equipment with rated current above 16 A draws a reference current below 16 A under the test conditions, the manufacturer may 1) comply with the calculated proportional limits with a chosen Rsce, 2) comply with the absolute limits of IEC 61000-3-2:2011 (Table 1) using the measurement procedure of 4.2.2 — then stating “Equipment complying with IEC 61000-3-12” in the instruction manual without declaring a minimum short-circuit power Ssc — or 3) change the test conditions to a representative 2,5 min period as for long cyclic equipment and comply with the proportional limits; the manufacturer is strongly advised to state in the test report which way was used. Scope (1): limitation of harmonic currents injected into the public system; equipment with rated input current above 16 A up to and including 75 A per phase, for public low-voltage systems: up to 240 V single-phase two or three wires, up to 690 V three-phase three or four wires, 50 or 60 Hz; other systems excluded; the limits of this edition apply to 230/400 V, 50 Hz systems (note 1: for other systems in a future edition); equipment above 75 A — requirements for installations (IEC/TR 61000-3-6, future IEC/TR 61000-3-14); not applicable to equipment connected only to private low-voltage systems supplied from the public network at medium or high voltage (the manufacturer should make this clear in the documentation); professional equipment up to 16 A not complying with IEC 61000-3-2 — as in Annex C; not applicable to stand-alone harmonic filters; the standard defines requirements and emission limits and methods for type tests and simulations — conformity can also be shown by validated simulation. References (2): IEC 60038, IEC 60050(161), IEC 61000-2-2, IEC 61000-2-4, IEC 61000-3-2 (in edition 2.1 — 2018 with amendment 1:2020), IEC 61000-4-7. Terms (3): THC — square root of the sum of squares of harmonics of orders 2–40; PWHC — square root of the sum of h·Ih² for orders 14–40 (reduces the effect of higher harmonics without individual limits); point of common coupling PCC; single-phase, interphase, three-phase, balanced and unbalanced three-phase, hybrid equipment; short-circuit power Ssc = U²nominal / Z (Z — system impedance at the PCC at power frequency); rated apparent power Sequ: Up·Iequ (single-phase), Ui·Iequ (interphase), √3·Ui·Iequ (balanced three-phase), √3·Ui·Iequ max (unbalanced); reference current Iref (according to 4.1, for establishing limits); rated current Iequ (from the rating plate or documents); short-circuit ratio Rsce: Ssc/(3·Sequ) for single-phase, Ssc/(2·Sequ) for interphase, Ssc/Sequ for three-phase (Rsce is not Rsc of IEC 61000-2-6); in edition 2.0 also stand-by mode, phase angle of the 5th harmonic relative to the fundamental phase-to-neutral voltage (Figures 1 and 2) and professional equipment (specified by the manufacturer). Measurement conditions (4, edition 2.0): reference current — average r.m.s. current measured by the averaging method of 4.2.2, under the conditions of 7.4 (dimmers at maximum conduction angle); for the original conformity assessment the manufacturer may specify any value within ±10 % of the measured one and both are given in the test report; in other tests, if the measured current is within 90–110 % of the manufacturer’s value, Iref equals the manufacturer’s value, outside this band — the new measured value (4.1); the limits apply to line currents for all types of power connection and load (4.2.1); for each order the 1,5 s smoothed r.m.s. value is measured in each DFT window according to IEC 61000-4-7 and the arithmetic average over the entire observation period is calculated (4.2.2); repeatability of the average better than ±5 % of the limit with the same equipment, conditions, system and climate — this requirement serves to define the observation period, not to assess compliance (4.2.3); at starting and stopping the first 10 s or the time until fully in or out of operation (whichever is longer) are disregarded, and the equipment may be in stand-by mode for no more than 10 % of the observation period (4.2.4); the average of each harmonic shall not exceed the limit from Tables 2–5, each 1,5 s smoothed value — 150 % of the limit, and for THC and PWHC harmonics below 1 % of Iref are disregarded (4.2.5); the test report gives the measured current and the manufacturer’s value, the Rsce used for calculation or test, the required minimum Rsce and the table applied (4.2.6); observation period (Table 1): quasi-stationary and random — until repeatability is met, short cyclic (up to 2,5 min) — at least 10 cycles (reference method) or a duration or synchronization ensuring repeatability, long cyclic (over 2,5 min) — full equipment program cycle (reference method) or a representative 2,5 min period with the highest THC (4.2.7).

STATUS (PKN catalogue cards as of 02.10.2026). The card of PN-EN 61000-3-12:2012 (English version, published 31-01-2012, 29 pages, price group N) has no “Withdrawn” heading: Information and Communication Technologies Sector, KT 104 Electromagnetic Compatibility, ICS 33.100.10, Directive 2014/30/EU, “Replaces: PN-EN 61000-3-12:2007 – Polish version”, additional element PN-EN 61000-3-12:2012/A1:2024-11. The card of the amendment PN-EN 61000-3-12:2012/A1:2024-11 (English version, published 14-11-2024, 16 pages): “Introduces: EN 61000-3-12:2011/A1:2024 [IDT], IEC 61000-3-12:2011/AMD1:2021 [IDT]”. The card of PN-EN 61000-3-12:2007 (Polish version) has the “Withdrawn” heading: withdrawal date 31-01-2012, replaced by the 2012 edition; the card of PN-EN 61000-3-12:2005 (English version) — withdrawn 16-07-2007, replaced by the 2007 edition; both editions introduced EN 61000-3-12:2005 and IEC 61000-3-12:2004.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, data up to 17.09.2026, read 02.10.2026). The number 61000-3-12 appears in 14 records at 7 laboratories: AB 082 (7), AB 261 (2), AB 167, AB 171, AB 666, AB 1132, AB 1925 (1 each). In the current scopes on the PCA website (read 02.10.2026, issues from 10.07.2025 to 04.08.2026) the 2012 edition with amendment A1:2024-11 is given by AB 167, AB 171, AB 666 and AB 1132 (the latter written “PN-EN IEC 61000-3-12:2012”), the 2012 edition alone by AB 261 and AB 1925; AB 082 gives the withdrawn 2005 edition for the vehicle items (UN Regulation No 10), and in one item the 2012 edition. In the scope of AB 171 (issue No 21 of 13.05.2026) the part of the scope marked in bold italics was suspended at the request of the body — the lines with PN-EN 61000-3-12 are not marked so. The “Laboratories” tab (“PN-EN 61000-3-12”) shows 5 laboratories (AB 082, AB 171, AB 261, AB 666, AB 1925); AB 167 and AB 1132 have entries starting with the number PN-EN 61000-3-2 or PN-EN IEC 61000-3-2, so they do not appear in this tab — checked with the tab query on the production server labcoda.pl on 02.10.2026.

WHAT THE LABORATORIES TEST (PCA entries). Harmonic currents of electrical and electronic equipment with phase supply current up to 75 A (AB 167), “current harmonics and interharmonics” (AB 261), “limits for harmonic current emissions” of electrical and telecommunication products (AB 1132), harmonic currents of industrial, scientific and medical equipment (AB 1925), harmonic emission of single-phase and three-phase household and industrial equipment (AB 666), harmonic emission within a broad item of disturbance emission (AB 171); vehicles of categories M, N, O, L, T, their sub-assemblies and equipment and vehicles with AC cables — emission of harmonics according to UN Regulation No 10 (AB 082).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. Reference current: the limits are calculated from Iref, not from the rated current on the rating plate; in subsequent tests the manufacturer’s value applies only when the measured current is within 90–110 % (4.1). Current below 16 A under test conditions: the interpretation sheet gives three ways and advises stating in the test report which one was used. Evaluation: in addition to the average over the observation period, no 1,5 s smoothed value may exceed 150 % of the limit; harmonics below 1 % of Iref are not included in THC and PWHC (4.2.5). Observation period: for long cyclic equipment the reference method is the full program cycle, and a representative 2,5 min period with the highest THC is an allowed alternative indicated by the manufacturer (Table 1). Starting: the first 10 s after switching are disregarded, and stand-by may last no more than 10 % of the observation period (4.2.4). Edition: AB 082 cites the withdrawn 2005 edition for the vehicle items, and the entry “PN-EN IEC 61000-3-12:2012” (AB 1132) does not match the designation on the PKN card (without “IEC”).

WHAT WE DO NOT STATE. We do not have Clauses 4.3–7 or the annexes: the limit values from Tables 2–5, how they are read depending on Rsce, the procedure for a reference current below 16 A from 5.3, the product documentation requirements, the test and simulation conditions (Clause 7, Annex A) — so we do not state any limit or Rsce value; nor do we know what amendment 1 of 2021 changed beyond Clauses 1–3.

Method principle

The reference current Iref is determined (average r.m.s. current, manufacturer’s value within ±10 %), each harmonic current is measured as the 1,5 s smoothed r.m.s. value in DFT windows according to IEC 61000-4-7, averaged over an observation period chosen for the equipment behaviour and compared with limits depending on the short-circuit ratio Rsce; in addition no smoothed value may exceed 150 % of the limit, and THC and PWHC are calculated without harmonics below 1 % of Iref.

Applications

• Electrical and electronic equipment with input current above 16 A up to 75 A per phase — 7 laboratories in PCA scopes
• Vehicles and their sub-assemblies with AC cables — emission of harmonics according to UN Regulation No 10
• Type tests and assessment of conformity with EMC requirements (Directive 2014/30/EU on the PKN card)

Key parameters

Standard

Standard number

PN-EN 61000-3-12:2012 (wersja angielska; EN 61000-3-12:2011 IDT, IEC 61000-3-12:2011 IDT) ze zmianą PN-EN 61000-3-12:2012/A1:2024-11 (EN 61000-3-12:2011/A1:2024 IDT, IEC 61000-3-12:2011/AMD1:2021 IDT)

Title (PL)

Kompatybilność elektromagnetyczna (EMC) — Część 3-12: Poziomy dopuszczalne — Poziomy dopuszczalne emisji harmonicznych prądu dla odbiorników o znamionowym prądzie fazowym > 16 A i < lub = 75 A przyłączonych do publicznej sieci zasilającej niskiego napięcia

Title (EN)

Electromagnetic compatibility (EMC) — Part 3-12: Limits — Limits for harmonic currents produced by equipment connected to public low-voltage systems with input current >16 A and ≤75 A per phase

Step-by-step procedure

1. Qualification of the equipment

   Input current above 16 A up to 75 A per phase, public low-voltage network; the type of equipment (single-phase, interphase, balanced or unbalanced three-phase, hybrid) determines the table of limits. PN-EN 61000-3-12:2012 with amendment A1:2024-11 applies (PKN cards as of 02.10.2026).

2. Reference current

   Average r.m.s. current by the method of 4.2.2 under the conditions of 7.4; manufacturer’s value within ±10 %, both in the test report.

3. Observation period

   According to Table 1: quasi-stationary and random — until repeatability of ±5 % of the limit is met; short cyclic — at least 10 cycles; long cyclic — full program or 2,5 min with the highest THC; without the first 10 s after switching, stand-by at most 10 % of the period.

4. Measurement of harmonics

   For each order, the 1,5 s smoothed r.m.s. value in each DFT window (IEC 61000-4-7), arithmetic average over the entire observation period.

5. Evaluation and report

   Averages ≤ limits from Tables 2–5 for the Rsce used, each smoothed value ≤ 150 % of the limit, THC and PWHC without harmonics < 1 % of Iref; in the report Iref measured and specified, Rsce, required minimum Rsce and the table applied.

Required equipment and apparatus

Health and safety (OHS)

• The standard contains no safety warnings in the part we read; the test is carried out at mains voltage and high currents — the laboratory sets the electrical safety rules
• TECHNICAL NOTE: the repeatability of ±5 % serves to define the observation period and is not a compliance criterion (4.2.3)

Frequently asked questions