USB to 1-Port Isolated RS-422, RS-485, RS-530 DB25 Serial Interface Adapter

Part: 2104   Model: SeaLINK+485I

(1 customer review)


Need some help? Contact us


The 2104 USB serial interface adapter provides one isolated RS-422 or RS-485 serial port for control and automation applications. Isolation helps to prevent damage caused by ground loops and surges. Power for the SeaLINK+485I is obtained directly from the USB cable, eliminating the need for wall power.

Sealevel’s SeaCOM USB software drivers and utilities make installation and operation easy using Microsoft Windows and Linux operating systems. After installing the software, simply connect the SeaLINK® serial interface adapter to your USB port and the device is immediately recognized by the system as a standard serial port.

Do you know that adapter design can impact your application? Find out how in this USB Serial performance report.


Additional information



Optically Isolated


USB Powered


Storage Temperature

0°C to 70°C (32°F to 158°F)

Serial Connector(s)


RoHS Compliant


Power Requirement

+5V @ 100mA

# of Ports


Operating Temperature

0°C to 70°C (32°F to 158°F)

Max Data Rate

921.6K bps

Communications Chip


Max Data Distance

4000 feet

Host Interface(s)


Humidity Range

10 – 90% Relative Humidity, Non-Condensing

High Retention USB


Electrical Interface

RS-422, RS-485, RS-530


3.8" (L) x 2.3" (W) x 1.0" (H)9.66 cm (L) x 5.84 cm (W) x 2.54 cm (H)

USB Specification

1.1 Compliant2.0 Compatible

  • Compliant with RoHS and WEEE directives
  • Configurable for RS-422, RS-485, or RS-530
  • Optical isolation provides protection against transients and group loops
  • High-speed UART with 128-byte Tx FIFO and 384-byte Rx FIFO
  • Data rates to 921.6K bps
  • Automatic RS-485 enable/disable
  • Hot-swappable
  • Powered by USB connection
  • Sealevel software supports Windows 98SE/ME/2000/XP/Vista and Linux operating systems
  • DB-25M connector
  • Includes 6′ USB device cable (Item# CA179)

Windows Software

Software: SeaCOM - Windows

Linux Software

Software: SeaCOM - Linux


Manual: 2104

1 review for SeaLINK+485I

  1. N. Smith

    2104 Review
    We have been using hundreds of the 2104 RS-422 to USB adapters reliably for 8+ years and would recommend to anyone needing this type of application.

Add a review

Your email address will not be published. Required fields are marked *