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Async RS-232 to RS422/485 interface converter DB9 to Terminal Block

Convert async RS232 to RS422/485 at speeds up to 115.2 kbps with distances up to 4000 ft over CATx cables in Class 1 Div 2 industrial environments with DIN Rail mounting.


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

*Required field

Product Features

  • This converter features 10–48-VDC operation and withstands temperature extremes.
  • UL® approved.
  • Three-way isolation, 2000-V input/output.
  • Class 1 Div 2 environments.


  • Operates from -40° to +176° F (-40 to +80° C).
  • Converts unbalanced half- or full-duplex RS-232 signals to balanced full-duplex RS-422 or 2-wire half- or 4-wire full-duplex RS-485.
  • Extends communications up to 4000 feet (1219.2 m).
  • Wide range of data rates.
  • Features addressing up to 32 nodes.
  • Modbus ASCII or RTU compatible.
  • Automatic Send Data Control eliminates the need for driver software.
  • Removable terminal blocks.
  • Conveniently mounts on optional DIN Rails.
  • Surge suppression has 600 W peak power dissipation.

  • Tech Specs

    Approvals CE, RoHS2
    Connectors (1) 5-position terminal block, (1) DB9 F (DCE)
    Dimensions 4.9"H x 4.1"W x 1.3"D (12.4 x 10.4 x 3.3 cm)
    Distance 4000 ft. (1219.2 m) maximum
    Operating Environment Temperature: -40° to +176° F (-40 to +80° C); Humidity: Up to 95% noncondensing
    Operation RS-232: Half- or full-duplex; RS-422: Full-duplex; RS-485: 2-wire half-duplex or 4-wire full-duplex
    Power +10 to -48 VDC (±20%) or from optional DIN Rail 12-VDC Power Supply (PSD100)
    Speed 1200 bps to 115.2 kbps; 2400 bps to 38.4 kbps, switch-selectable

    This product works with:
  • DIN Rail (DR100)
  • DIN Rail 12-VDC Power Supply (PSD100)
    Questions? Contact our FREE Tech Support.

    * 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.

  • Support


    Double Diamond Warranty

    Extended 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $24.72

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $49.44


    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 to RS422/485 interface converter DB9 to Terminal Block 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.