Power Supply with PFC: An NDR-75-24 Nameplate Is Not a Power-Factor Report
An RFQ that asks for a power supply with PFC needs more than a familiar model number or a photograph of its output rating. For an NDR-75-24 evaluation, separate three questions: which exact configuration is being offered, what the manufacturer declares about power-factor correction, and what input measurements support the stated power factor. A nameplate identifies a specimen; it does not answer the other two questions.
This is a documentary qualification guide, not a finding that the pictured model has or lacks PFC. It does not provide a mains-probing procedure, a measured result, or permission to connect the illustrated receiver equipment.
Start with the specimen, not the family headline
The original blue front identifies NDR-75-24 and shows INPUT 100–240VAC 1.6A 50/60Hz and OUTPUT 24V DC 3.2A. There are four upper output contacts, marked −V, −V, +V, +V, and three lower contacts marked protective earth, N and L. The metal case is 32mm wide, 125.2mm high and 102mm deep. Preserve that exact variant and its source revision in the purchasing record.
The retained WEHO NDR-75 specification sheet has an efficiency entry but no explicit PF or PFC row. That observation applies to the reviewed document, not every configuration ever supplied. Missing disclosure is not proof of missing circuitry. A public family description or a different conditional input-current field must not overwrite the photographed 1.6A label.
Keep four claims in four evidence columns
| Requested claim | Appropriate evidence | What cannot replace it |
|---|---|---|
| PFC feature present | Manufacturer declaration tied to full model, ordered configuration and document revision | Case shape, nominal wattage or absence of a table row |
| Specified power factor | Condition-bound input-power report identifying the evaluated specimen | Output voltage and current printed on its label |
| Conversion efficiency | Input and output power results for the stated operating point | A power-factor figure alone |
| Harmonic compliance | Applicable test report with its scope and configuration | A PFC declaration or the photographed CE artwork alone |
A supplier may close one column while another remains open. Record each status separately rather than turning a partial answer into an unconditional acceptance. A useful reply specifies the covered revision and conditions; “PFC type” without those links leaves the procurement question unresolved.
Ask what belongs in the PF report
Power factor compares real input power with apparent input power. The referenced power-factor measurement explanation identifies PF as P/S and defines real power over an identified time interval. For procurement, this means the numerator and denominator must belong to the same condition and interval, not unrelated catalog numbers. Keep the report’s real watts, apparent VA, RMS voltage and RMS current fields visible and preserve its stated calculation method.
Request the specimen identifier, full model and revision; input voltage and frequency; load state and actual output demand; stabilization conditions; measurement interval; instrument and method identification; and the reported PF with its scope or uncertainty where provided. These are record fields to request from a qualified evaluator, not instructions for connecting probes to live conductors.
Keep the manufacturer’s declaration and the evaluator’s result as separate dated attachments. If a later quotation changes the revision or substitutes a different supply, do not carry the earlier report forward solely because both labels say 24V. Require an explicit coverage link or reopen that qualification item.
Do not divide 24V × 3.2A by an input-nameplate quantity and call the result PF, efficiency or actual consumption. The output label is not simultaneous input real power. Likewise, an efficiency percentage in the retained table is not a measured PF figure and supplies no universal PF acceptance threshold.
Review the ordered configuration before harness release
Keep the installation drawing separate from electrical qualification. The photographed rear hook and spring release clip locate the DIN rail at the back of the 102mm-deep case; they do not validate an input-power claim. The real 24V specimen also has a side opening that the retained drawing annotates differently for another variant. Preserve the observed specimen and request ordered-revision confirmation instead of editing that difference away.
When the requirement states a minimum PF, the responsible project owner should identify its input and load conditions and the acceptable evidence before ordering. This article supplies no invented limit and does not turn a photograph, marketing sentence or search failure into a release decision.
Send a request that can be answered
Ask WEHO to identify the offered NDR-75-24 revision, state whether that exact configuration includes PFC, and provide the condition-bound PF evidence needed for the named requirement. Attach the source identity and keep unresolved columns open until the corresponding documents arrive. That produces an auditable answer without confusing a nameplate with a power-factor report.
