Fiber Optic Connector Type Guide | Generated by AI
Question: What does LC-LC, SC-SC, etc. mean for fiber optic cables?
Answer:
LC-LC, SC-SC, and similar notations describe fiber optic patch cables (also called jumper cables) by specifying the connector types on each end.
- LC-LC means the cable has an LC connector on both ends.
- SC-SC means the cable has an SC connector on both ends.
- Other common examples include LC-SC (LC on one end, SC on the other), ST-ST, FC-FC, MTP-MTP, and so on.
These are the most widely used types of duplex (two-fiber) patch cords in networking, data centers, telecom, and fiber-to-the-home installations.
What do LC and SC stand for?
- LC → Lucent Connector (also called Little Connector or Local Connector)
- Uses a small 1.25 mm ceramic ferrule.
- Very compact size (about half the footprint of SC).
- Uses a small latch clip to lock in place (similar to an RJ45 clip).
- Dominant in modern high-density environments like data centers, SFP/SFP+/QSFP transceivers, and high-speed switches/routers.
- SC → Subscriber Connector (also called Square Connector or Standard Connector)
- Uses a larger 2.5 mm ceramic ferrule.
- Square-shaped body with a push-pull mechanism and a locking tab.
- Very common in older telecom equipment, PON networks (GPON/EPON), cable TV, and many enterprise installations from the 1990s–2010s.
Quick comparison of LC vs SC
| Feature | LC Connector | SC Connector |
|---|---|---|
| Ferrule diameter | 1.25 mm | 2.5 mm |
| Size / footprint | Small / high-density | Larger |
| Latching mechanism | Small latch clip | Push-pull with tab |
| Typical use today | Data centers, 10G/25G/40G/100G+ | Telecom, PON, older equipment |
| Density in panels | Higher (more ports per space) | Lower |
| Insertion / durability | Good, but smaller latch | Very robust, easy to handle |
Both LC and SC provide excellent optical performance (low insertion loss and high return loss) and can be used with single-mode or multi-mode fiber.
Other common notations you might see
- LC-SC → Hybrid cable (one end LC, one end SC) — often used when connecting new equipment to older infrastructure.
- LC-LC Duplex → Specifies two fibers (most common patch cable style).
- LC/UPC-LC/UPC → Adds polish type (UPC = Ultra Physical Contact, most common; APC = Angled Physical Contact for lower reflection in some single-mode applications).
In short: LC-LC = both ends are small modern LC connectors, SC-SC = both ends are larger classic SC connectors.
References:
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[Fiber Optic Connector Types Explained FiberCablesDirect](https://fibercablesdirect.com/content/23-fiber-optic-connector-types-explained) - LC vs SC Connectors: Which to Choose? - VCELINK
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[Comparing SC and LC Fibre Optic Connectors iTel Networks](https://itel.com/blog/comparing-sc-and-lc-fibre-optic-connectors) -
[Fiber-optic connectors: SC vs. LC Arrow.com](https://www.arrow.com/en/research-and-events/articles/fiber-optic-connectors-sc-vs-lc)