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Async RS-232 RS422 RS485 extender fiber Terminal Block to SC SM

Extend RS232, RS422 or RS485 protocols over single mode fiber up to 9 miles so different types of equipment can talk to one another in point to point or multipoint industrial environments.


12 In Stock
Same Day Shipping (before 5PM ET)
Extended Double Diamond™ Warranty Available (3 Additional Year)

*Required field

Product Features

  • Supports serial data rates to 115.2 kbps.
  • Extends communications up to 9 miles (15 km).
  • IP30-rated, industrial, DIN-mounted enclosure.
  • 3 Way 2kv optical isolation.
  • Modbus ASCII or RTU compatible.
  • Removable terminal blocks.


The MED102A is our premium serial to single-mode fiber optic converter. It provides versatile connections between asychronous full- or half-duplex serial equipment using duplex single-mode fiber optic cable. The converter can also be set up in a multi-drop configuration to allow one serial device to communicate with multiple devices on a fiber ring. It supports mixed standards, which allows you to replace other converters and isolators and add the EMI/RFI protection inherent to fiber optic communications.

Tech Specs

Bus Compatibility MODBUS ASCII or RTU
CE Yes
Connectors (1) 2-position terminal block, (1) 5-position terminal block, (1) duplex single-mode SC
Data Rate Up to 115.2 kbps
Enclosure IP30 Plastic Case
Interface RS-232/422/485
Isolation 2 KV RMS for 1 Minute 3 Way
Power Input: 10 to 48 VDC, external; Consumption: 1.4 W
Range 9 mi. (14.4 km)
Size 3.5"H x 1.2"W x 5.0"D (8.9 x 3 x 12.8 cm)
Weight 0.5 lb. (0.2 kg)

* Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.


Double Diamond Warranty

Extended 1 Year Warranty Available

Protect your purchase with an additional 1 Year Double Diamond™ warranty!
Cost: $40.00

Extended 3 Year Warranty Available

Protect your purchase with an additional 3 Year Double Diamond™ warranty!
Cost: $79.99


Double Diamond™ Warranty (Standard)

Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

The Async RS232 RS422 RS485 extender fiber Terminal Block to SC SM comes with a standard 5 Year Double Diamond™ Warranty (Standard) already included.

During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

Plus, get an Extended Double Diamond Warranty.

You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

* Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.