W&T connects
Interfaces for TCP/IP, Ethernet, RS-232, RS-485, USB, 20mA, glass and plastic fiber optic cable, http, SNMP, OPC, Modbus TCP, I/O digital, I/O analog, ISA, PCI
Data sheet:

ST fiber-optic line <> RS422/RS485 interface

  • Glass fiber RS422/485 Interface model 61210

Connect industrial interfaces over glass fiber optics

The model 61210 Interface transmits serial RS422 and RS485 data via multi-mode glass fiber optics over a distance of up to 3800 meters.



  • 1 x RS422/RS485
    • 9-pin Sub-D plug
  • 1 x multi-mode fiber optic cable
    • ST connector

Management and connectivity:

  • No re-configuration of transmission parameters required
  • Transmission of two data channels
  • Noise-immune transmission over a distance of up to 3800 meters
  • Galvanic isolation up to nearly any value between the connected devices

Voltage supply:

  • External
    • 12V-24V DC via plug-in screw terminal
    • Galvanically isolated power connection

Standards & more

  • Conforms to standards both in office and industrial environments:
    • High noise resistance for industrial environments
    • Low noise emission for residential and business areas
  • 5 year guarantee

Worth knowing

Data transmission over long distances and in extremely noisy environments make the use of fiber optics the logical choice as a physical transmission medium.

The use of plastic fiber optics allows easy-to-install connections over relative short distances of up to 100 meters. But for distances above this limit the use of glass fiber optic cable is unavoidable.

While distances of up to 4km are easily accomplished with multimode fiber optics, greater distances are the domain of singlemode fiber optics.

It used to be that routing and assembling glass fiber optics created significant problems for the users, but today - thanks to the wider use of glass fiber technology in networking - many companies are offering this work as a service.

Technical data

Connections and displays:

Serial port:   RS422/RS485 port
9-pin SUB-D adapter
Glass fiber optics port:   ST plug adapter
Operating modes:    RS422
RS485 4-wire with automatic control
RS485 2-wire with automatic control
Switching time:   approx. 10µs for switching from data send to receive
for RS485 automatic control (can be changed on request)
Baud rate:    0..1.5Mbaud
Data format:   any format
Supported signals:   RxD, TxD
Fiber-optic medium:   Multi-mode fibers 50/125μm, 62,5/125μm
Wavelength:   820nm
Optical budget:   50/125µm: typically 9.6dB, min. 4.2dB
62.5/125µm: typically 13.4dB, min. 8.0dB
Maximum distance:   50/125µm: typically 3200m, min. 1400m @3dB/km
62.5/125µm: typically 3800m, min. 2200m @3.5dB/km
Galvanic isolation:   Isolation voltage min. 1kV DC between supply and serial connection
Supply voltage:   12..24V AC/DC
Current consumption:   typ. 80mA @12V DC, 40mA @24V DC
Supply connection:   Plug-in screw terminal, 5.08mm spacing
Labeled "L+" and "M"
Displays:   1x LED Data
1x LED Power

Housing and other data:

Housing:   Plastic housing for top hat rail installation
105 x 22 x 75mm (L x W x H)
Enclosure rating:   IP20
Weight:   approx. 100g
Ambient temperature:   Storage: -40..+70°C
Operating in non-rowed installation: 0..+60°C
Operating in rowed installation 0..+50°C
Permissible relative humidity:   5..95% RH (non-condensing)
MTBF:   716.382h @25°C per MIL-HDBK-217
Life expectancy:   > 25 years at 25°C ambient temperature
Scope of delivery:   ST fiber-optic line <> RS422/RS485 interface
Please order power supplies separately as accessories


  • Power supplies

    • Plug-in power supply, 24V / 500mA DC with Euro plug
    • 11021
    • 19.00€
    • Plug-in Power Supply, 24V / 750mA DC with Euro, US and UK plug
    • 11026
    • 34.00€
    • Power Supply for DIN rail mount, 24V / 1A DC
      (merchandise, 2-year manufacturer’s guarantee)
    • 11084
    • 49.00€
  • Cable and Connector Accessories

    • DB9F connection cable with open cable ends, left angled, 1.5m
    • 11902
    • 16.00€
    • 9-pol. SUB D socket with soldering terminals and shielded housing
    • 11904
    • 9.00€
    • 9-pol. SUB D socket with screwing terminal and shielded housing
    • 11905
    • 19.00€
  • FO-Accessories

    • Patch cable ST/ST, 1 meter, 50/125um
    • 81901
    • 14.00€
    • Patch cable ST/ST, 2 meters, 50/125um
    • 81902
    • 19.00€
    • Patch cable ST/ST, 5 meters, 50/125um
    • 81905
    • 24.00€
    • Patch cable ST/ST, 10 meters, 50/125um
    • 81910
    • 34.00€
    • Patch cable ST/ST, 15 meters, 50/125um
    • 81915
    • 39.00€
  • Mechanical Accessories

    • Mounting bracket for wall mounting
    • 58812
    • 9.98€
    • 19" DIN rail
    • 58813
    • 19.00€

* Our offering is intended only for commercial users. We will be happy to refer private end customers to trading partners through whom our products can be purchased.