OM3 LC Fiber Patch Cable: Multimode Reach
Quick answer / TL;DR: Short answer: OM3 is laser-optimised multimode supporting 10GBASE-SR to about 300 m and 40G/100G over shorter distances with the right optics. Use LC connectors with UPC polish (aqua jacket), duplex or duplex-pair construction, and confirm polarity (A-B or A-A) against the link design. Beyond OM3's reach, single mode is the answer.
An OM3 LC fiber patch cable is the workhorse multimode cord of the data center: laser-optimised 50-micron fiber, LC connectors, aqua jacket, and enough reach for 10G across a hall. It is cheaper than single mode at the optics, and shorter in reach – which is the trade that decides its use.
This is the OM3 guide: what the grade supports, the connector and polish details, and the polarity convention that trips up first-time installations.
What OM3 Supports
| The rate | The typical reach | The note |
|---|---|---|
| 1G | About 550 m | Legacy margin |
| 10G | About 300 m | The main use |
| 40G | Shorter, optics-dependent | Parallel optics |
| 100G | Shortest of the three | Inside a row |
The reach falls as the rate rises: the same fiber carries more lanes and less distance.
The Connector Details
- LC: the small-form connector that dominates data centers
- UPC polish: the standard for multimode; APC is for single mode and PON
- Duplex clip: holds the pair together, keeps polarity consistent
- Aqua jacket: the conventional OM3 colour, not a specification
The polish rule matters: APC mated to UPC loses signal, and multimode plants are almost always UPC.
Polarity
| The method | The result |
|---|---|
| A-B (crossed) | Standard duplex link |
| A-A (straight) | For specific transceiver pairs |
| Unlabelled | The most common field fault |
Standards and Verification
| The reference | The relevance |
|---|---|
| ISO/IEC 11801-1 | OM3 fiber definitions |
| TIA-568.3 | Fiber cabling practice |
| IEEE 802.3ae | 10GBASE-SR |
| Power meter test | Loss per link against the budget |
Per-SKU loss figures are not provided in the knowledge base. The reach figures are standard for the grade; verify with a loss measurement rather than assuming the datasheet reach.
Real-World Applications
The hall link
A cross-hall link at 10G over 180 m: OM3 duplex LC, UPC polish, polarity A-B recorded at both ends – the link tested inside its loss budget first time.
Related reading: Single mode where OM3 runs out of reach — blogs/news/single-mode-fiber-patch-cable
Related reading: Buying fiber cords in volume — blogs/news/fiber-patch-cord-suppliers
Frequently Asked Questions
How far does OM3 run at 10G?
About 300 m with standard 10GBASE-SR optics.
OM3 or OM4?
OM4 reaches further at the same rates. Choose by the distance and the optics you already own.
UPC or APC for OM3?
UPC – multimode plants are normally UPC. APC belongs to single mode and PON.
What is polarity A-B?
The duplex pair is crossed end to end, which is the standard for a duplex link.
Sourcing cables for a project, a store, or a private-label line? Contact our B2B sales team for specifications, certification evidence, and volume terms – FOB and CIF options available. Request a quote or sample.