Grandstream F-SM1310-20KM-1.25G SFP Fiber Module
Frequently Asked Questions
First, reseat the module firmly in the SFP slot until it clicks—a loose connection is the most common cause. Next, ensure the switch ports support 1.25Gbps SFP optics (most Gigabit SFP ports do) and that the module is properly inserted with the correct orientation. If it still isn't detected, power cycle the switch to reinitialize the port.
Overheating is possible, especially if the module is in a poorly ventilated switch or patch panel. Check the switch's internal temperature via its web interface and ensure airflow isn't blocked. Also verify that the fiber connectors are clean—dirty ends can cause intermittent signal loss that looks like a heat-related drop.
Actual range depends on the quality of your fiber run, including splices, connectors, and the overall loss budget. Check the DDM readings: the receive power should stay above -18dBm. If it's borderline, inspect all fiber connections for dirt or damage, and confirm you're using single-mode fiber (not multi-mode).
Low receive power usually points to an issue on the fiber link, not the module itself. First, clean both ends of the fiber connectors with a lint-free swab and isopropyl alcohol. If the reading stays low, check for tight bends or pinched cables along the run. If the transmit power is also outside normal range, the module may need replacement.
Yes, this module follows the SFP MSA standard, so it should work in any brand’s SFP port that accepts standard optics, including Cisco. Some Cisco switches may log a generic 'unsupported transceiver' warning but will still function. If you need a Cisco-specific module, you can still use this one as a compatible alternative.
It is not recommended. Single-mode SFPs and multimode fiber are designed for different core sizes—using them together will cause high signal loss and likely no link or very short range. Stick to single-mode fiber (typically yellow jacket) for this module to get the full 20km distance.
DDM lets you monitor real-time parameters like temperature, voltage, and optical power levels of the SFP module. On Grandstream managed switches, you can view DDM data through the web interface under a 'SFP Diagnostics' or 'Transceiver' menu. It's useful for proactively spotting degrading performance before a link fails.
Check that both ends of the fiber pair are connected to the correct ports—LC connectors are usually labeled A (Tx) and B (Rx) and must be crossed between the two modules. Also verify that the switch ports are administratively up and configured for the correct VLAN or trunk settings.
Fiber connectors are very sensitive to oil and dust. Use a dry, lint-free fiber cleaning pen or a one-click cleaner designed for LC connectors. Avoid using cloth or your fingers—you can push contaminants deeper. If you don't have a proper cleaning tool, contact your IT supplier for a cleaning kit.
10GBase-LR ports operate at 10Gbps, while this module is rated for 1.25Gbps. Plugging a 1G SFP into a 10G port may not work, and if it does, it will only negotiate at 1G speed—and many 10G ports don't support 1G SFP modules. Check your switch documentation to confirm backward compatibility; otherwise, use a 10G-rated SFP+ module for 10G links.
Accessories
Grandstream F-SM1310-20KM-1.25G SFP Fiber Module
* Hot-pluggable small-form factor transceiver modules with high sensitivity PIN receiver and signal conditioner for 1.25/10 Gigabit Ethernet applications • Low EMI and excellent ESD protection • Single-mode fiber module featuring low power consumption, ideal for enterprise LAN networks and optical links Key Features: • Single-Mode Fiber • 1310nm Wave-Length • 20-Kilometer Transfer Distance • 1.25Gbps Data Rate • Low Power Consumption Technical Specifications: Model: F-SM1310-20KM-1.25G Fiber Mode: Single-Mode Fiber Connector Type: Duplex LC DDM: Yes, I2C for integrated Digital Diagnostic Monitoring Nominal Wavelength: 1310nm Data Rate: 1.25Gbps SFP Max Power Consumption: 1W Transfer Distance: 20km TX Power: -9 to -3dBm, ±3dB RX Power: -18 to -1dBm, ±3dB Operation Voltage: 3.3V±0.3V Standards: SFF-8472, SFP MSA, IEEE 802.3z, RoHS-6
About This Product
This Grandstream SFP module is built for extending network links over single-mode fiber, making it a solid fit for organizations that need to connect separate buildings, floors, or equipment rooms beyond the reach of standard copper Ethernet. In a typical VoIP deployment, it plugs into any MSA-compliant SFP port on a managed switch and pairs with a matching module on the far end, carrying traffic for desk phones, call servers, and internet uplinks. The 20-kilometer range covers most campus or multi-building setups, while the 1310nm wavelength and low power consumption keep the link stable and efficient. For a small single-site office with all equipment in one room, this module is overkill—copper Ethernet would be simpler and cheaper. Conversely, if you need 10Gbps uplinks currently or in the near future, this 1.25Gbps module won't meet that demand, so plan accordingly. Canadian businesses, particularly ones in the GTA with multiple office locations or warehouse campuses, will find it a cost-effective way to bridge fiber without replacing their existing switches.
Services We Provide
- Professional Installation & Configuration
- Ongoing Maintenance & Support
- Troubleshooting & Repairs
- System Upgrades & Updates
