# Media converter Black Box LMC270A-MM-ST 10/100 Mbps RJ45 to 100BASE-FX multimode ST

**URL:** https://aio.lv/en/product--black-box-lmc270a-mm-st--11515579
**Data updated:** 2026-02-15 12:44 (EET)
**Category:** Network Media Converters
**Manufacturer:** black box
**Manufacturer code:** LMC270A-MM-ST
**Warranty:** 2 Years
**Availability:** Out of stock

## Summary description

Black Box LMC270A-MM-ST is a media converter that converts 10/100 Mbps Ethernet (RJ45) to 100BASE-FX over multimode fiber with an ST connector. It allows copper Ethernet devices to connect to fiber-optic networks, extending link distance and improving immunity to electrical interference. Suitable for office, campus or industrial networks requiring fiber uplinks or segment extension.

## Long description

Black Box LMC270A-MM-ST is a compact media converter that converts 10/100 Mbps Ethernet (RJ45) to 100BASE-FX over multimode fiber with an ST connector. The device enables connectivity between copper-based Ethernet equipment and multimode fiber links, extending network segments beyond the limits of twisted-pair cabling and providing enhanced immunity to electrical noise and ground-loop problems. Its form factor fits rack or desktop environments in offices, campuses and industrial sites where fiber uplinks or segment extension are required.
Advantages
The converter supports automatic negotiation on the copper port and a fixed 100 Mbps fiber interface, ensuring straightforward integration with existing 10/100 Mbps equipment. By using multimode fiber and an ST connector, it allows longer transmission distances compared with copper and reduces susceptibility to electromagnetic interference. The unit's compact design and low power consumption simplify deployment in constrained spaces, while transparent Ethernet forwarding preserves VLAN and MAC-level traffic characteristics.
Suitable for
Extending Ethernet links between buildings, floors or remote closets
Connecting switches, routers or servers to a multimode fiber backbone
Removing ground-loop or EMI issues on copper Ethernet runs
Upgrading segments to fiber where fiber uplink ports are required
Key specifications
Data rates: 10/100 Mbps on copper port; 100 Mbps on fiber port
Copper interface: RJ45, auto MDI/MDIX, auto-negotiation supported
Fiber interface: 100BASE-FX multimode with ST connector
Fiber type: multimode (MM) for short- to medium-range links
Network forwarding: transparent Ethernet layer 2 forwarding
Power: low-voltage DC input (check product label for required adapter)
Form factor: compact desktop/rack-friendly enclosure
How to use
Install the converter near the copper device or at the fiber termination point. Connect the RJ45 Ethernet cable from the copper device to the RJ45 port on the converter and insert the multimode ST fiber connector into the fiber port. Apply the appropriate DC power supply and verify link/activity LEDs to confirm a successful connection. If connecting to equipment with fixed speed settings, ensure the copper side is set to a compatible speed or uses auto-negotiation.
Usage recommendations
Place the converter in a ventilated, dry location away from strong electromagnetic sources. Use matched multimode fiber cable and quality ST connectors for reliable links, and verify distance limits for multimode fiber runs. When integrating into managed networks, document the converter location and link details to aid future troubleshooting.

## FAQ

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All black box products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized black box service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

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