Author: Huang Publish Time: 26-01-2026 Origin: Site
There’s no single winner; the right office LED panel depends on what you optimize for. Use these fast picks to narrow the field.
Target panels in the ~120–140 lm/W minimum, ~140–160+ lm/W preferred band with CRI ≥ 80; keep optics comfortable (UGR under 19 where applicable). Choose simple 0–10V group dimming or wireless mesh when you must avoid new control wiring.
Specify CRI ≥ 90 (check R9 if available) with low-glare optics that can achieve UGR under 19 for workstations and meeting rooms. DALI addressable control makes scenes, daylighting, and fine dimming straightforward.
Wireless Bluetooth Mesh or Zigbee nodes/controllers preserve line power and add scheduling, sensor control, and scenes via apps; confirm interoperability and site RF layout.
Ask vendors for LM-80 data and TM-21 projections; prioritize robust thermal design and L70 within the 50,000–100,000-hour range under stated temperatures. Verify assumptions and warranty terms.
The table below compares category-level tiers you’ll encounter in 2026. Values are indicative ranges; verify any purchase against current spec sheets, LM-79 tests, and listings.
Tier | Typical lm/W band | CRI (Ra/R9) | UGR target | Dimming/control options | L70 evidence (TM-21 within LM-80 limits) | Thermal notes | Typical warranty | Best for |
Energy-first | ~140–160+ | Ra ≥ 80 (check R9 ≥ 0 if noted) | < 19 at workstations | 0–10V group dim, wireless retrofit | L70 stated with LM-80 + TM-21 | Adequate heatsinking, rated Ta | 3–5 years | Fast payback retrofits |
Color-critical | ~120–140 | Ra ≥ 90 (seek decent R9) | < 19 (or < 16 for drawing) | DALI addressable scenes | L70 stated with LM-80 + TM-21 | Lower luminance diffusion | 3–5 years | Meeting/design rooms |
Retrofit-wireless | ~130–150 | Ra ≥ 80 | < 19 | Bluetooth Mesh/Zigbee | L70 stated with LM-80 + TM-21 | Check ambient temps | 3–5 years | Minimal control rewiring |
Long-life focus | varies by optic/CRI | Ra ≥ 80/90 | < 19 | Any (verify driver) | Higher L70 projections (within TM-21 limits) | Strong thermal path | 5+ years | Maintenance-sensitive sites |
Pick the tier aligned to your scenario, then confirm the exact numbers and evidence in the product’s documentation or listings.
Efficacy: lm/W often varies with CCT, CRI, optics, and drivers; treat bands as wayfinding, not absolutes. Cross-check with an LM-79 report or trusted spec sheet.
CRI and R9: Offices generally run Ra ≥ 80; conference/design rooms may benefit from Ra ≥ 90. R9 helps with saturated reds, useful in skin tones and materials review.
Dimming/control: 0–10V is simple analog group dimming; DALI is digital, addressable; wireless mesh suits retrofits without new control cabling. Match the interface to project scale and commissioning appetite.
Lifetime: TM-21 projections must be based on LM-80 data; projections can’t exceed 6× the tested hours. Confirm the temperature assumptions used to claim L70.
Definition and why it matters: Luminous efficacy is luminaire output lumens divided by input watts (lm/W). Higher efficacy reduces energy and operating cost at the same illuminance level.
What good looks like in 2026: For office panels, ~120–140 lm/W is a solid minimum target and ~140–160+ lm/W is a strong preferred range, subject to optics/CRI/driver choices. Always confirm with a spec sheet or LM-79.
How to verify: Check the LM-79 test or manufacturer datasheet; compute lumens ÷ watts yourself. For on-site sanity checks, measure average lux on the workplane, multiply by area (m²) to estimate delivered lumens, and compare against expected results.
Caveats: Efficacy differences across CCT/CRI, microprism diffusers, and driver choices are normal; don’t compare numbers out of context.
Evidence links: LM-79 measures complete luminaires’ photometric and electrical performance; see independent lab explainers and program requirements in the DesignLights Consortium’s testing-lab notes and LM-79 overviews: the Asselum standards page and DLC lab requirements provide clear guidance (Asselum LM-79/LM-80/TM-21 page; DLC testing-lab requirements).
Office baseline: For general office areas, EN 12464-1 practice commonly cites a minimum CRI (Ra) of 80 and recommends controlling glare (UGR under 19) at VDU workstations. Overviews and explainers from reputable sources summarize these targets (Any-Lamp summary of EN 12464-1; Performance in Lighting EN 12464-1 explainer).
When to specify Ra ≥ 90: Use higher CRI for color-critical tasks and premium spaces such as design review rooms or high-visibility conference spaces; when available, check R9 to ensure reds don’t look dull.
TM-30 context: If TM-30 metrics (Rf/Rg) are provided, they offer a more detailed fidelity/gamut picture than simple Ra; consider them as tie-breakers.
Practical tip: Don’t chase CRI at the expense of glare control; a CRI 90 panel with poor optics will still cause discomfort in an open office.
Evidence links: Summaries of EN 12464-1 also highlight the workplane and surrounding area concepts, including UGR targets and vertical illuminance for faces; see Collingwood’s office lighting guide for practical interpretation (Collingwood open-plan office guide).
0–10V analog: Best for small/simple retrofits, 0–10V uses a pair of control conductors for group dimming without feedback. It’s cost-effective but not addressable. For a concise comparison with DALI, see technical explainers from reputable vendors (Boca Lighting 0–10V vs DALI overview; CMD protocols comparison).
DALI digital (IEC 62386): Suitable for large projects and new builds, DALI offers addressing, grouping, scenes, sensors, and diagnostics over a two-wire bus with software-based commissioning. The DALI Alliance publishes specifier guides and system notes (DALI at a glance for specifiers; DALI systems guide).
Wireless mesh (Bluetooth Mesh or Zigbee): Ideal when you must avoid new control wiring. These systems add scheduling, sensors, and scenes via apps; design the network carefully for range and latency (Bluetooth SIG commercial lighting brief; CSA Green Power 1.1.2 note).
Flicker expectations: Evaluate percent flicker or flicker index at full output and at dim levels; aim to fall within IEEE 1789’s recommended regions, especially for sensitive populations. For background and research resources, see the U.S. DOE’s solid-state lighting flicker hub (DOE flicker research overview).
Commissioning and maintenance notes: 0–10V has fewer software steps but less flexibility; DALI requires addressing/grouping and benefits from trained commissioning; wireless needs site surveys and robust app management. Choose based on scale, staffing, and integration needs.
What L70 means: L70 is the number of hours until a luminaire’s light output falls to 70% of initial. It’s projected using LM-80 test data for the LED package/module and TM-21 methods for extrapolation.
TM-21 guardrails: A projection can’t exceed 6× the LM-80 test duration, and the projection conditions must match or be justified relative to the luminaire’s thermal environment (Tc/Ta). Ask for the test temperatures, drive current, and in-situ temperature data.
Reading a claim: “L70 100,000 h” is plausible only if backed by long-duration LM-80 data at representative temperatures and a TM-21 calculation within limits; otherwise, treat as marketing.
Evidence links: See Cree LED’s lumen-maintenance application note and an IES explainer on lumen maintenance for accessible descriptions of these methods (Cree LED TM-21 note; IES article on lumen maintenance). Also consult DLC’s test-report expectations for submissions (DLC testing-lab requirements).
Define the workplane: Offices typically measure illuminance at desk height; many teams use 0.8–0.85 m. EN 12464-1 methodology highlights task area, immediate surrounding, and background zones with uniformity considerations (Performance in Lighting EN 12464-1 explainer).
Build a measurement grid: Lay out a rectangular grid across the task area with consistent spacing; a 1 m grid spacing is a practical starting point in open offices. Use a calibrated, cosine- and color-corrected meter; let luminaires stabilize before readings. For workplace survey basics, see CCOHS guidance (CCOHS lighting survey).
Target levels and comfort: A common target for open-plan offices is around 500 lx average on task areas, with UGR under 19 at workstations; drawing spaces may aim for lower UGR (≤16) per practice summaries (Any-Lamp EN 12464-1 summary).
Sanity-check conversion: Average lux × room area (m²) ≈ delivered lumens to the workplane. It ignores utilization and maintenance factors but helps flag major mismatches with LM-79 data or layout calculations.
Documentation: Record grid, meter model/calibration date, ambient light conditions, and stabilization time; keep this with project closeout files.
Example (illustrative): Suppose an LED package’s LM-80 test shows 96% lumen maintenance at 10,000 h at Tc 55°C. TM-21 fitting yields an L70 projection at 62,000 h under similar thermal conditions. Because TM-21 limits the projection to 6× the test hours, reporting 60,000–62,000 h is within guardrails, but only if the luminaire’s in-situ temperatures are comparable.
What to request: Ask for the LM-80 raw table (test hours, temperatures, currents), the TM-21 spreadsheet output, and any in-situ temperature measurement (ISTMT) linking the package environment to the actual luminaire.
▉Setup: You’re replacing 100 older panels drawing 45 W each with 100 new panels at 32 W each (similar light levels). That’s 13 W saved per panel.
Annual energy saved: 100 × 0.013 kW × 3,000 h/year ≈ 3,900 kWh. At $0.15/kWh, that’s about $585/year. If the incremental cost is $6,000, simple payback is a little over 10 years; incentives or higher efficacy can shorten that.
Sensitivity: If you instead choose a ~150 lm/W tier that gets power down to ~28 W (same lumens), savings rise to 17 W/panel, ~5,100 kWh/year, or ~$765/year at the same rate—improving payback.
If energy savings and quick payback are the priority, choose the higher-efficacy tier with CRI ≥ 80 and simple group dimming (0–10V) or wireless as needed.
If color fidelity and presentation quality matter most, choose CRI ≥ 90 with good R9, low UGR optics, and DALI for scene control.
If you must avoid new control cabling, choose Bluetooth Mesh or Zigbee wireless controls with compatible drivers/controllers and plan a site survey.
If your aim is fewer service calls, choose products with strong LM-80 data, TM-21 L70 in the 50,000–100,000-hour range under realistic temperatures, and durable thermal design.
Disclosure: KEOU Lighting is our product. For category context and customization options (including dimmable and smart-control variants) see the panel light hub; it’s a useful starting point if you need tailored sizes or control interfaces for projects (KEOU panel light category). For broader office application context, see the indoor solutions overview (KEOU indoor lighting solutions).
General office areas typically work well at Ra ≥ 80 with glare controlled to UGR under 19; for meeting or color-critical rooms, Ra ≥ 90 and attention to R9 is advisable, with low-UGR optics. See summaries of EN 12464-1 practice for context (Performance in Lighting EN 12464-1 explainer).
They report total lumens and input watts from LM-79 tests or equivalent lab measurements; divide lumens by watts. On site, measure average lux at the workplane and multiply by area to estimate delivered lumens; compare to LM-79 and your layout calcs (Asselum LM-79/LM-80/TM-21 page).
Choose Bluetooth Mesh or Zigbee when avoiding control rewiring, or when app-based commissioning and flexible zoning are desirable. Ensure network planning for coverage and latency (Bluetooth SIG commercial lighting brief).
Q4:How do I take photometer readings for acceptance testing?
Define the workplane (often 0.8–0.85 m for desks), build a consistent grid (e.g., 1 m spacing), use a calibrated meter, allow stabilization, and document conditions. Aim for ~500 lx average in open-plan task areas and check UGR targets where applicable (CCOHS lighting survey; Any-Lamp EN 12464-1 summary).
