LC to ST Fiber Patch Cable - Single Mode OS2 9/125μm Duplex

ST was the standard fiber connector for a long time, and there's still a lot of it in service: media converters, older switches, wall-mount enclosures, and the patch panels in buildings wired in the 1990s and 2000s. New equipment is almost all LC. This cord connects the two, with a pair of LC/UPC connectors on one end for the SFP or LC panel and a pair of ST/UPC bayonet connectors on the other for the ST port or panel, so you can put a new switch behind an existing ST fiber plant without re-terminating anything.

It's OS2 single-mode fiber, 9/125 µm, in a duplex configuration for a transmit and receive pair. Each cord is tested and the end-faces are checked by interferometer before it ships.

Features

• LC/UPC to ST/UPC. Snap-in LC on one end, twist-lock ST bayonet on the other, both flat-polished UPC.
• OS2 single-mode, 9/125 µm. For 1310 and 1550 nm links, from a patch panel jumper to a campus or metro span.
• Duplex. Two fibers for a matched transmit and receive pair.
• Low insertion loss. 0.15 dB typical per connector.
• Return loss 50 dB or better, the standard UPC figure.
• Ceramic ferrules, 1.25 mm on the LC end and 2.5 mm on the ST end, checked by 3D interferometry for end-face geometry.
• Bayonet ST coupling. Push, quarter-turn, and it's locked; it won't pull out of a panel by accident.
• ETL Listed for the US and Canada (Intertek 4009521), and RoHS compliant.
• Thirteen lengths from 1 to 30 m.

Where It Fits

It suits connecting a new LC-based switch or SFP to an existing ST patch panel, linking a media converter or older switch with ST ports to LC equipment, phased upgrades where the fiber plant stays on ST while the electronics move to LC, building-to-building links terminated on ST enclosures at one end, and any single-mode link between an LC port and an ST port.

Good to Know

Both ends are UPC, so this cord is for blue LC ports and standard ST ports; if the LC side is a green APC port, you need a different cord. The two ST connectors aren't keyed to each other the way a duplex LC clip is, so polarity is set by which ST plug goes into which port: if the link doesn't come up, swap the two ST ends and try again before troubleshooting anything else. ST ferrules are 2.5 mm, so use a 2.5 mm one-click cleaner on that end and a 1.25 mm on the LC end, and keep dust caps on until the moment you plug in; a fingerprint on a single-mode ferrule costs more than the whole cord's loss budget. To seat an ST, line up the key on the plug with the slot on the port, push in against the spring, and turn clockwise until it stops; a half-seated ST is the most common cause of a "bad" fiber link. If both ends of your link are LC, you want the LC/UPC to LC/UPC cord instead. For runs longer than 30 m, or where the cord will be pulled through a tray or conduit, ask about a 3.0 mm jacket or an OFNR-rated cable.

Specifications