Grandstream F-SM1310-20KM-1.25G SFP Fiber Module

The Grandstream F-SM1310-20KM-1.25G is a Gigabit SFP transceiver for single-mode fibre, running at 1310 nm over distances up to 20 km.

This is the module for distance rather than speed. Twenty kilometres reaches between sites in a town, across a large estate or out to a remote building that will never see a copper cable. If the far end is a warehouse, a pumping station, a depot or a second office across the ring road, this is the one.

Buy them in pairs. A fibre link needs a module at each end, and both ends must match — same fibre type, same wavelength, same speed. A single-mode module will not talk to a multi-mode one, and mismatched ends are the most common reason a fibre link fails to come up on the day.

Key features

• 1.25 Gigabit SFP transceiver
• Single-mode fibre, 1310 nm
• Up to 20 km — the longest reach in the range
• Genuine Grandstream module — matched to Grandstream switch SFP slots

Works with

• GWN7803 — four SFP slots
• GWN7801 — two SFP slots
• F-SM1310-10KM-10G — single-mode at 10G, 10 km
• F-MM850-550M-1.25G — multi-mode for in-building runs
• Grandstream GWN switches

Frequently asked questions

Do I need one or two?

Two — one at each end of the fibre. Ordering one is an easy mistake and it stops the whole job.

Single-mode or multi-mode — which fibre do I have?

Single-mode fibre is usually yellow; multi-mode is usually orange or aqua. If the fibre is already installed, the module must match the glass. For a new run between sites, single-mode is the right choice.

Why 1.25G rather than 10G at this distance?

Because most long links do not need ten gigabits, and the Gigabit module costs considerably less. A link between a main office and a depot is usually carrying a handful of phones, some cameras and file access — nowhere near a gigabit.

Will it work in a non-Grandstream switch?

Often, but some switches only accept their own vendor's coded modules. If the far end is another brand, check its compatibility list before ordering.

Is 20 km realistic?

It is the rated maximum in ideal conditions. Real runs include splices, patch panels and bends that all consume optical budget, so leave headroom rather than planning to the limit.

Planning a fibre link? Call 0333 242 1314 or email sales@clisecure.com — tell us the distance, the fibre type and the switches at both ends and we will match the modules.