A credible beam or spacing discussion should not stop at wattage, lumen, or a marketing rendering. Buyers should ask for the IES photometric file, the LM-79 evidence path behind it, the exact model-to-distribution mapping, and any simulation-use notes before comparing suppliers.
Start by defining what needs to be verified
Street-light, floodlight, and high-bay discussions often drift because one supplier is talking about beam angle, another is talking about optical distribution, and a third is showing only a lighting render. A cleaner buyer-side review begins by asking which file actually supports the claim and whether it belongs to the exact model under discussion.
Product category
Clarify whether the file check is for road lighting, area and flood lighting, or warehouse and high-bay lighting.
Exact model
Ask which model, wattage, optics code, or lens option the beam claim belongs to.
Claim type
Separate beam-angle talk from spacing, uniformity, glare, or application-fit claims.
File path
Confirm whether the supplier can provide an IES file, an LM-79 path, and any simulation context that matches the actual order option.
Ask for the photometric evidence as a matched set
Buyers get a cleaner comparison when the photometric file, test path, and model identity are reviewed together. A single beam chart image or a generic PDF rarely answers whether the proposed luminaire really matches the discussed application.
| Buyer question | Why it matters |
|---|---|
| Can you share the IES photometric file for the exact model and optics under discussion? | Prevents a generic catalog claim from being mistaken for model-specific beam evidence. |
| What LM-79 or equivalent test path supports the photometric data? | Helps the buyer understand where the photometric file came from and whether it has a defensible measurement basis. |
| How does this file map to the quoted wattage, CCT, lens, and housing option? | Many luminaire families have multiple optical or power variants that should not be compared as one beam pattern. |
| Is the file intended for DIALux, AGi32, or another simulation path, and are there any usage notes? | Clarifies whether the buyer is reviewing a usable planning file or only a high-level sales attachment. |
| What file revision or export date should we treat as current, and does it match the latest quoted option? | Reduces the risk of comparing an old photometric file against a newer quotation or optics update. |
Check whether the photometric file still matches the real mounting and accessory path
Beam claims often drift when the planning file describes one luminaire condition while the order discussion quietly changes mounting brackets, tilt, visors, shields, diffusers, or lens codes. Buyers should ask the supplier to confirm whether the file still represents the actual installed condition under review.
Mounting orientation
Ask whether the file assumes horizontal, tilt-mounted, bracket-mounted, pendant, or hook-mounted installation.
Accessory effect
Confirm whether visors, shields, louvers, diffusers, or other accessories change the file being referenced.
Optics code path
Verify that the file belongs to the exact lens or distribution code, not only the luminaire family name.
Quoted condition
Ask whether the current quotation still maps to that same file after wattage, CCT, housing, or bracket changes.
Use the photometric file to test beam logic, not just to collect another attachment
An IES file becomes useful when it helps the buyer test whether the luminaire fits the project geometry and expectations. The goal is not to demand every possible document. The goal is to avoid accepting spacing or beam claims that cannot be traced back to a real measurement path.
- Check whether the file helps explain the optical distribution being discussed, not only a simplified beam-angle label.
- Ask whether road, yard, parking, flood, or warehouse use cases are being mixed together under one optics claim.
- Review whether the proposed mounting height, pole spacing, aiming angle, or rack layout assumptions were stated anywhere.
- Confirm whether the same luminaire family has alternate optics that change the beam pattern or simulation result.
- Ask whether glare, spill-light, or uniformity concerns were considered, especially for outdoor area lighting and high-bay applications.
- Check whether the file path still matches the quoted accessory set, tilt condition, and current revision date.
This page does not claim that New Pengfei Lighting currently has buyer-ready IES files, LM-79 reports, or simulation-delivery support for every street light, floodlight, or high-bay model. Buyers should use the checklist to ask, compare, and verify supplier replies model by model.
Photometric review only works when site inputs are clear
Even a good photometric file can be misused if the project input is vague. Buyers should pair the file review with basic application inputs so the supplier response can be judged against real use conditions instead of abstract beam language.
Useful buyer inputs
- Road width, lane count, pole arrangement, or area dimensions.
- Mounting height, bracket or aiming condition, and spacing target.
- Warehouse ceiling height, rack layout, or open-area context for high bays.
- Any glare, spill-light, dark-sky, or window-light sensitivity concerns.
What buyers should not assume
- Do not assume one beam-angle label proves the luminaire fits your site layout.
- Do not assume a rendering or lux plot is enough if the underlying file is missing.
- Do not assume one optics file applies across every wattage or housing option in a family.
- Do not assume a photometric file alone proves pricing, certification, or project-delivery readiness.
Ask extra questions when spacing or simulation results are being used to close a decision
If a supplier is using the file to justify pole spacing, rack-aisle coverage, floodlight aiming, or consultant-facing simulation output, buyers should separate file availability from project-ready interpretation.
| Extra buyer question | Why it reduces drift |
|---|---|
| Was this spacing or lux result generated from the same file revision being shared with us now? | Prevents old simulations from being reused after optics or mounting assumptions change. |
| Are any aiming, tilt, pole-arm, or rack-row assumptions built into the simulation that are not yet fixed on site? | Separates file evidence from still-pending project assumptions. |
| Does the file review cover only the luminaire output, or also the installed accessory and mounting condition? | Helps the buyer understand whether the comparison is optics-only or installation-condition specific. |
| Which file items are fixed, and which still depend on final layout, bracket, or control decisions? | Keeps buyers from treating a provisional simulation package as a finished submittal condition. |
A simple message buyers can send before comparing beam claims
Please confirm the exact model, optics code, mounting condition, and any visor or shielding option under discussion, share the current IES photometric file that matches that condition, explain the LM-79 or equivalent test path behind it, and note any spacing, aiming, rack-layout, or simulation assumptions we should treat as fixed versus still pending for our project.