SFP Fiber Optic Transceiver TP-LINK ISM311LM — 1.25 Mbit/s, 850 nm, LC, 550 m, grey

TP-LINK ISM311LM is an SFP fiber optic transceiver module designed for short-range Ethernet links. It supports a data rate up to 1.25 Mbit/s over multimode fiber at an 850 nm wavelength, uses an LC (UPC) connector and provides a reach of up to 550 m. The module is intended for use in switches and routers to extend uplink distances, features a grey housing and operates from a 3.3 V input. It is compatible with 1.25 Gigabit Ethernet interfaces and carries FCC/CE compliance for network deployments.

Advantages

The module offers hot-pluggable installation for quick replacement or upgrade without powering down equipment. Its compliance with SFP-MSA ensures interoperability with a broad range of SFP-capable devices. The ISM311LM supports Digital Diagnostic Monitoring (DDM) to monitor optical parameters and link status. Its industrial operating temperature range extends applicability to harsher environments where extended temperature tolerance is required.

Suitable for

• Uplinks between switches and routers within short-range multimode fiber networks
• Industrial network segments requiring extended temperature tolerance
• Network equipment deployments where hot-swappable optics reduce downtime
• Cost-conscious installations that choose fiber modules as needed to extend reach

Key specifications

• Maximum data transfer rate: 1.25 Mbit/s
• Maximum transfer distance: up to 550 m (multimode fiber)
• Wavelength: 850 nm
• Connector type: LC (UPC)
• Ethernet interface compatibility: 1.25 Gigabit Ethernet
• Input voltage: 3.3 V
• Form factor: SFP (hot-pluggable)
• Product colour: Grey
• Operating temperature range (industrial): -40 to 85°C
• Supports Digital Diagnostic Monitoring (DDM)

How to use

Power off the host device if recommended by the device manufacturer, insert the ISM311LM module into an SFP slot until it latches securely, and connect LC fiber patch cables to the module. After insertion, verify link status on the host switch or router and confirm optical parameters via DDM if supported by the management interface. To remove, disengage the latch and pull the module straight out; protect transceiver ports and fiber ends with dust caps when not connected.

Recommendations

Use single-mode/multimode fiber consistent with the module specification and ensure LC patch cables are clean before mating. For reliable operation, match transceiver wavelength and fiber type at both ends of the link, monitor DDM readings for signal health, and follow your equipment manufacturer’s compatibility list to avoid interoperability issues.