A 10m cob led strip is usually selected when a project needs a longer continuous light line than a standard cabinet run, but the length on the reel is only the starting point. Whether the project uses 1m, 3m, 5m, 10m, 20m or custom-length COB strip, the real question is not “can the strip be this long?” — it is “can the strip stay bright, safe, serviceable and visually consistent across the full run?”
This guide covers how to plan length and reels for commercial ceilings, corridors, cabinets, hotel coves and custom linear work within the broader COB LED Strip category. It explains where low-voltage COB is sufficient, where power injection is required, and where reel planning has to change.
Reel Length and Electrical Run Length Are Not the Same Thing
This distinction causes more disappointment than any other point in length planning, so it is worth settling first. A 10m reel describes how much strip arrives on the spool. The electrical run length is how much strip can be fed from one connection point while staying within acceptable voltage drop. The second is almost always shorter than the first.
Buying a 10m cob led strip therefore does not mean connecting 10m to one driver output. It means having 10m of material to distribute across however many electrical runs the design requires. A 10m line might be one continuous strip fed at each end, two 5m runs fed separately, or one strip with an injected feed at the midpoint — visually identical, electrically different.
The permitted run per feed depends on the wattage per metre and the copper weight of the specific product, so it is a figure to request rather than infer. As a rough guide a typical 24V strip supports around 5m per feed and 12V roughly half that, but a high-wattage strip supports less.
Start With the Run Map, Not the Total Metres
Before choosing a model, draw the installation as separate runs. A project totalling 40 metres may be four 10m runs, eight 5m runs, or one corridor divided into driver zones — three layouts with different power, wiring and maintenance plans, and different prices.
- How many separate runs are there, and how long is each?
- Where can a driver physically be installed, and how far is that from the strip?
- Is the strip seen directly, or hidden in a cove and seen only as reflected light?
- Can the installer reach connectors and feed points after the ceiling or joinery is closed?
- Do the runs need to switch and dim together as one apparent line?
The last two questions are the ones most often skipped, and both are expensive to answer late.
1m, 3m, 5m, 10m and 20m COB Strip Lengths
Have an LED Lighting Project?
Share your project requirements — our engineering team will configure the complete LED strip system (strips + profiles + controllers + power supplies) and send you a detailed proposal within 24 hours.
Different lengths call for different planning methods, even when the strip itself is identical.
| Length option | Typical use | Main planning point |
|---|---|---|
| 1m | Samples, display shelves, short cabinet sections | Easy testing and simple power, but tells you nothing about uniformity at full length |
| 3m | Furniture grooves, small coves, decorative lines | Check cutting points against the exact groove and plan the connector position |
| 5m | Standard reel length, common indoor work | Usually near the single-feed limit at 24V; confirm wattage and driver capacity |
| 10m | Longer coves, office ceiling lines, corridor sections | Requires a feed strategy — centre feed, dual-end feed, or split into zones |
| 20m or custom reel | Long commercial runs and project supply | Always zoned; also a joining and colour-batch question, not just an electrical one |
Note that a standard 5m reel is not an arbitrary convention — it sits close to the practical single-feed limit for many 24V strips, which is why it became the default packaging. A 10m cob led strip crosses that limit by definition, which is exactly why it is a feed-planning decision rather than a purchasing one.
Voltage and Run Length: Why 24V Is Usually Preferred
For a given wattage, current is inversely proportional to voltage, so a 24V strip carries half the current of a 12V strip producing the same light. Halving the current halves the voltage drop along the same copper, which is why 24V typically supports roughly twice the run length per feed. The full reasoning is in the 24V COB LED strip guide.
Two consequences catch people out:
- Voltage drop is not linear along the run. Current is highest at the feed end, because that section carries the current for everything downstream. Loss accumulates fastest near the feed, so brightness falls off in a curve rather than a straight line.
- Drop in the feed cable counts too. A long thin cable from a remote driver can lose more voltage than the strip itself. Include the cable run in the calculation.
For very long exterior runs, mains-voltage strip is sometimes proposed to avoid this problem. It does reduce the number of drivers, but it brings fixed cutting units, limited dimming and stricter safety requirements — the trade-offs are set out in the 120V COB LED strip guide.
Four Feed Patterns for Long COB Runs
Single-end feed
One driver, one connection, suitable for short runs comfortably inside the single-feed limit. Simple and reliable, and the correct choice whenever the length allows it.
Centre feed
Feeding a 10m cob led strip at its midpoint creates two 5m electrical runs from one connection. This is often the single most effective change available and needs no extra driver — only a feed point the installer can reach at the centre. The trade-off is that the brightest part of the line sits in the middle rather than at one end, which is usually less noticeable.
Dual-end feed
Cabling to both ends of the run from the same driver output halves the effective electrical distance in the other direction, leaving the dimmest point in the centre. Useful where a centre feed position is inaccessible but both ends are reachable.
Zoned runs with multiple drivers
For a corridor, commercial ceiling or long cove, divide the installation into zones, each with its own driver, feed and service access. This is better engineering than forcing one long electrical run, and it contains failures: one driver fault takes out one zone rather than the whole line.
Zoning introduces one requirement that is easy to miss. If the zones must appear as a single continuous line, their dimming has to track together. Drivers of the same model and firmware batch on the same control protocol will match; mixed drivers frequently will not, and the mismatch shows at low dim levels rather than at full output. Specify identical drivers across zones that share a visible line.
Voltage Drop Symptoms in Long Runs
Voltage drop rarely appears in a bench test and shows up once the full run is installed. These are the signs:
- The far end reads dimmer than the feed end, with the falloff steepest near the feed.
- Colour temperature shifts slightly warmer along the run, because LEDs driven at lower current shift in colour as well as output.
- The strip flickers or drops out at low dim settings while behaving normally at full brightness.
- Connectors or feed wires run warm under full load.
- The driver runs hot, buzzes, or shuts down intermittently when all runs switch on together.
The colour shift is the symptom most often misdiagnosed as a batch problem. If a run looks warmer at one end and the strip came from a single reel, suspect the feed before suspecting the supplier. For general background on LED efficiency, the US Department of Energy publishes neutral guidance; wiring and code compliance must follow local rules and a qualified installer.
Product Options for 10m and Custom-Length Planning
For length planning, the strip has to be chosen on voltage, wattage per metre, width and feed method rather than on density alone.
- COB LED Strip 320LEDs/m 8mm Single Color — available in 12V or 24V, 8 mm wide, CRI 90, IP20. Suitable for standard indoor linear work and cabinets. Specify 24V for anything beyond short segments, since the 12V option roughly halves the permissible run per feed.
- COB LED Strip 528LEDs/m 10mm 24V Single Color — 24V only, 10 mm wide, CRI 90, IP20. The wider PCB carries more copper, which helps on longer runs, but it needs a channel wide enough to accept it.
Both are IP20 and therefore for dry indoor positions only — the ingress classifications are defined by the IEC IP rating system, and a long run passing through a damp zone at any point needs a higher rating for that section. In both cases, confirm the wattage per metre and the manufacturer’s maximum run per feed for the exact variant, because those two figures — not the LED count — determine the driver and the feed plan.
Connector choice matters more as runs get longer, since a marginal contact that is harmless at 1 A becomes a warm spot and a voltage loss at 4 A. The options are compared in the COB LED strip connector and power supply guide.
Commercial Use Cases for Long Runs
Long COB planning appears wherever a light line has to read as continuous across a large space.
Office linear ceiling lighting
The office linear ceiling COB LED strip project illustrates the usual requirements: clean ceiling lines, consistent brightness between adjacent runs, driver positions that suit the ceiling void, and maintenance access designed in rather than added later.
Long corridor lighting
The long corridor COB LED strip project shows the central principle of this article: a line that appears continuous is normally divided into electrical zones behind the scenes. The visual design and the electrical design are separate decisions. Both are application references only — the right feed strategy for your own project depends on its lengths, driver positions and access.
Colour Consistency Across Reels and Joins
Length planning is not purely electrical. Once a run exceeds one reel, two further issues arise, and both are visible in the finished job.
The first is colour matching. Strips from different production batches can differ slightly in colour temperature — within specification, but perceptible where two lengths meet end to end in one line. Colour tolerance is expressed in SDCM steps, a measure built on the colorimetric work of the International Commission on Illumination (CIE). Order the material for a continuous run from a single batch, ask for the binning tolerance, and keep spare from the same batch for later repairs.
The second is the join itself. Where two lengths meet there is a small gap in the emitting surface, because each strip ends with a solder pad rather than phosphor. In a deep cove this is invisible; in a shallow channel viewed directly it reads as a dark spot. Plan join positions deliberately — at a corner, behind an obstruction, or at a break in the architecture — rather than leaving them to fall wherever the reel runs out.
Custom Reel and Cut-Length Planning
For distributors, contractors and OEM buyers, custom reels reduce both waste and site labour. Rather than standard 5m or 10m cob led strip reels, a project can request pre-cut sections, pre-attached wire leads, labelled lengths, or reel lengths matched to the installation schedule. On a repetitive job — a hotel floor with the same detail thirty times — this is often the largest saving available, because it moves cutting and soldering from site to factory.
Confirm the cutting interval, solder pad position, lead length and orientation, labelling scheme, packaging length and reel direction, and how the sequence on the reel maps to the installation sequence. A custom reel that unwinds in the wrong order costs more time than it saves. Order a small margin of spare beyond the schedule as well: pre-cut sections remove the flexibility to absorb a site measurement error.
RFQ Checklist for Long-Run COB Strip
A length schedule lets a supplier recommend the right strip, reel, driver and wiring plan instead of quoting a reel price.
| RFQ item | What to provide |
|---|---|
| Run schedule | Every run length listed individually, not just the total metres |
| Voltage | 12V, 24V, or a mains-voltage requirement |
| Feed position | Single-end, centre, dual-end, or zoned with multiple drivers |
| Driver location | Distance from driver to strip, and whether the position is accessible |
| Continuity requirement | Which runs must appear as one line and dim together |
| Colour requirement | CCT, CRI, and whether continuous runs need single-batch material |
| Environment | Dry indoor, damp, exterior, ceiling void, cabinet, profile or cove |
| Accessories | Connectors, cable, aluminium profile, dimmer, driver, mounting clips |
| Packaging | Standard reel, custom reel, pre-cut lengths, labelling, plus spare allowance |
Mistakes to Avoid With a 10m COB LED Strip
- Assuming a 10m reel can be powered from one end, which is the root of most of the problems below.
- Reusing one driver plan across projects of different lengths and wattages.
- Excluding the driver-to-strip cable from the voltage drop calculation.
- Concealing drivers where they cannot be reached for replacement.
- Cutting before the final site measurement and the confirmed cutting interval.
- Treating a longer reel as a way to reduce the number of electrical zones.
- Choosing connectors for speed rather than current capacity and long-term reliability.
- Mixing driver models across zones that share a visible line, then finding they dim differently.
- Letting reel joins fall wherever the material runs out instead of placing them deliberately.
- Judging uniformity from a 1m sample.
FAQ About COB LED Strip Lengths
Can a COB LED strip be 10 metres long?
As a physical line, yes. As a single electrical run from one feed, usually not at low voltage. A 10m line normally needs a centre feed, a feed at both ends, or division into zones. Confirm the permitted run per feed for the specific product.
Is a 10m cob led strip better than two 5m strips?
They can be the same installation. What matters is the number of feed points, not whether the material arrived as one reel or two. Two separately fed 5m runs are usually more stable than 10m fed from one end.
Can I use a 20m COB LED strip?
Only with zoning, multiple feeds or a custom design. A 20m run also crosses reel boundaries, so colour batching and join positions need planning as well.
What is the best voltage for long runs?
24V for low-voltage work, since it roughly doubles the run per feed compared with 12V at the same wattage. Mains-voltage strip is a different trade-off and needs a compliance review.
Where should the power feed go on a 10m run?
The centre, if the installation allows it. That converts one 10m electrical run into two 5m runs with no extra driver — normally the most effective single improvement available.
Does power injection reduce brightness anywhere?
No. Injection adds a parallel feed so current does not have to travel the whole length through the strip’s copper. It raises voltage at the injection point back towards nominal, which lifts the dim section rather than dimming anything.
Why does the far end look warmer, not just dimmer?
Lower drive current shifts LED colour as well as output, so a voltage drop appears as a slight warm shift along the run. On single-batch material, suspect the feed before suspecting a colour-consistency problem.
Get a Length and Feed Plan for Your Project
Whether the project needs 1m, 5m, a 10m cob led strip or a custom reel schedule, it is quickest to resolve with the run list in hand. Prepare the individual run lengths, the intended voltage, where the driver can physically sit, the installation environment, whether any runs must read as one continuous dimmed line, and the accessories required. With that information a supplier can specify the strip, the feed pattern, the driver capacity and the reel format together instead of quoting metres. Send the run schedule to contact Senfey for a project-specific recommendation.
