Harmonic Current Limits and PFC for EN 61000-3-2: An OEM Evidence Checklist
For an OEM specification referencing EN 61000-3-2, “with PFC” is not enough to release a power supply or a finished machine. PFC describes a design function; acceptance requires evidence covering the applicable harmonic-current limits, equipment classification and test conditions. Procurement should request that evidence before approving a substitute or placing a production order.
The WEHO PSP-600-24 is a useful component example because its family documentation explicitly describes power-factor correction and the photographed sample is marked 24 V, 25 A. That does not, by itself, establish compliance of the sample or of equipment built around it.
First define what is being assessed
IEC 61000-3-2 addresses harmonic components of equipment input current for equipment within its scope, including rated input current up to 16 A per phase and connection to public low-voltage distribution systems. The IEC page lists the consolidated 2018 edition with 2020 and 2024 amendments. The BSI listing for the EN adoption identifies BS EN IEC 61000-3-2:2019+A2:2024.
Have the responsible compliance engineer or laboratory identify the applicable regional edition, amendments and interpretation sheets for the intended market. Do not determine the finished equipment’s scope from the power supply’s output wattage or its input label alone. Other mains-fed loads and the equipment’s rated input conditions belong in that decision.
Power factor and harmonic limits answer different questions
Power factor describes how real input power relates to apparent power at a stated operating point. Harmonic assessment examines the relevant components of the current waveform against the applicable limits. A favorable single PF figure therefore does not provide the harmonic-by-harmonic evidence needed for a pass decision.
Likewise, PFC is not the same as efficiency. A selection document should keep PF, losses, input current and harmonic results in separate fields. Do not promise a particular electricity-bill saving or network capacity increase from a product’s PFC description without a system-specific analysis.
What to request with a PSP-600-24 sample
| Evidence | Useful acceptance question |
|---|---|
| Model and revision | Do the report photographs, part number and hardware revision match the offered unit? |
| Report scope | Which standard edition, equipment class, limits and decision rule were used? |
| Operating conditions | Which input voltage, frequency, load and operating modes were assessed? |
| Results | Are individual harmonic results and the relevant limits available, rather than only a PF summary? |
| Integration | Does the evidence cover this component alone or the actual equipment configuration? |
The PSP-600 product page and the supplied single-page sheet describe PFC but do not present an exact-sample harmonic test report. Their PF conditions also differ. In addition, the photograph, sheet and web table differ on input details and some mechanical or power fields. Ask for one coherent offered-revision package; do not combine the most favorable entries from separate records.
Use a representative equipment configuration
List the power supply, other mains loads, controls and selectable operating modes that will be present in production. Ask the laboratory which combinations fall within the required test conditions. A component report can support that discussion, but it is not permission to ignore the rest of the equipment.
Keep sample and production configuration traceable: part revision, firmware where relevant, load settings, input arrangement and any external components specified by the assessment. If an alternative supply is proposed, compare the evidence scope as well as voltage, current and price. A replacement with the same output rating may change mains-current behavior.
Write the RFQ around evidence, not a badge
A useful RFQ states the destination market, product category, expected input supply, equipment operating modes and DC load schedule. Include the required report scope and the planned sample acceptance process. Ask whether supporting reports can be supplied for the quoted model and revision, and whether any configuration or operating limitations apply.
Contact WEHO with those requirements, the expected pilot and production quantities, and the enclosure layout. Request commercial terms separately. This makes alternative quotations comparable without assuming that a CE mark, a PFC heading or a family-wide claim resolves your project’s compliance obligation.
Procurement FAQ
Does a PF figure prove EN 61000-3-2 compliance?
No. It is one operating-point measurement or specification. It does not supply all the harmonic results, classifications and test conditions needed for the applicable assessment.
Can a power-supply report be reused for every machine using that supply?
Not automatically. Review what was tested and how the finished equipment differs. The responsible compliance assessment must cover the actual equipment boundary and applicable operating conditions.
Should a supplier change trigger a new review?
Yes. Recheck the exact revision, electrical fit and report coverage before accepting the substitution. The amount of additional assessment depends on the actual change and the project requirements.
