Model 276A


  • Data Rate to 1 MBPS
  • ST Connectors
  • DB-25 Connector
  • Half-duplex operation
  • Extends distance of RS-485 network to 6,600 ft (2 km) on multimode fiber cable

    Product Description

    The Model 276A provides the capability of transmitting an RS-485 signal via a fiber optic link. For applications where the transmission medium must be protected from electrical interference, lightning, atmospheric conditions or chemical corrosion fiber optics is the perfect solution. The Model 276A RS-485 to Fiber Optic Converter accepts half-duplex data rates to 1 MBPS. The RS-485 electrical interface is a balanced, half-duplex, digital interface, which is implemented in a female DB-25 connector. In an RS-485 network the control of data flow is determined by the designer. In order to provide the greatest versatility the Model 276A enables the RS-485 transmitter when data is detected at the fiber optic receiver. The fiber optic ports are implemented using the industry standard ST connectors. Mating cables should be 62.5/125 micron fiber cable. The optical signal wavelength is approximately 850nm. The optical power budget for the Model 276A is 12dB. A pair of Model 276A's will provide reliable communications over fiber where the loss is limited to 12 dB. This translates to distances of at least 2 km (6,600 ft). Power to operate the Model 276A is supplied by a small, wall-mounted transformer and line cord.

    Ordering Information


    Model Description Price Product Info
    276A 2 Wire, RS-485 to Fiber Optic Line Driver/Converter $169 Specs - Manual - App Notes
    276A-220 2 Wire, RS-485 to Fiber Optic Line Driver/Converter - 220 Volts $174 Specs - Manual - App Notes

    Telebyte Home Bomara Homepage Request Information

    Bomara Associates Phone: 800.5BOMARA (800.526.6272) Phone: 978.452.2299 Fax: 978.452.1169 3 Courthouse Lane, Chelmsford, MA 01824 USA
    Phone: 800.5BOMARA (800.526.6272)

    Phone: 978.452.2299


    Fax: 978.452.1169

    Email: bobr@bomara.com

      Web: www.bomara.com

    3 Courthouse Lane, Chelmsford, MA 01824 USA
    Serving the marketplace for over 40 years

    © 2014 by Bomara. All rights reserved


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