Digital-I/O Extender Set 8*In / 8*Out Singlemode SC


Transmit contact signals over very long distances

The Digital-I/O Extender Set transmits up to 16 digital I/O signals over single-mode glass fiber cable. The set consists of two Digital-I/O <> glass fiber optics and supports eight I/O channels in each direction.

Manufacturer: Wiesemann & Theis / Country of Origin: Germany


  • 8 x digital output
    • FET, short-circuit protected, 8..30V / 0.5A
  • 8 x digital input
    • Polarity reversal protected
  • 1 x Single-Mode Glass Fiber Cable
    • SC connector

Management and connectivity:

  • Noise-immune transmission of 16 I/O signals over a distance of up to 20km, e.g.:
    • in extremely noisy industrial environments
    • in areas subject to lightning strikes
    • between two distant buildings
    • in the mountains
    • ….
  • Safety-optimized solution
    • with no need for programmable components: No firmware risk
    • integrated monitoring of the fiber optic connection: Status output on each converter
    • configurable output response when glass-fiber cable is interrupted

Standards & more

  • Conforms to standards both in office and industrial environments:
    • High noise resistance per EN 61000-6-2
    • Low noise emission per EN 55032:2015 + A1 Cl. B, EN 61000-3-2 & EN 61000-3-3
  • 5 year guarantee

Worth knowing:

Although digital I/O signals are essentially insensitive to external noise due to their low bandwidth and the large voltage swing, as serial data signals for example the application conditions do still in many cases require transmission procedures which are completely resistant to local noise effects.

Glass fiber optic cables used as the transmission medium meet these requirements in ideal fashion and also offer the advantage of galvanic isolation of up to virtually any value between the connected devices. In installations which are subjected to high risk of lightning strikes, for example in outdoor locations or between distant buildings, such a solution ensures that the connected components will survive even under adverse conditions.

The W&T Digital-I/O Extender Set 8×8 is fully implemented in hardware, so that there is no principle risk of malfunction caused by hidden firmware errors or by a system crash.

The functionality of the glass fiber optic connection is cyclically monitored and the status indicated by means of an LED and a switching output. Should the connection fail, the fallback state can be individually set for each digital output.

Connections and displays:

  • I/O connection:
    • Plug-in screw terminal
  • Digital outputs:
    • 8 x Digital Out 8V-30V, 500mA, short circuit protected,
    • configurable response to failure of the optical connection
  • Digital inputs:
    • 8 x Digital In, max. input voltage ±30V,
    • protected against reverse connection within this range,
    • Switching threshold 9V ± 1V, “On” current = 2.2mA, per IEC 61131-2, Type 3
  • Glass fiber connection:
    • SC connector
  • Supported signals:
    • 16 digital signals (eight in each direction)
  • Signal propagation time:
    • Input to output: max. 20ms
  • Fiber-optic medium:
    • Duplex single-mode fiber optic 9/125μm
  • Fiber end face:
    • UPC (Ultra Physical Contact)
  • Transmitter type:
    • Class 1 Laser Product
  • Wavelength:
    • 1310nm
  • Optical output power:
    • min. -12dBm, max. -8dBm
  • Receiver sensitivity:
    • max. -22dBm
  • Maximum input power:
    • max. -3dBm
  • Optical budget:
    • min. 10dB
  • Maximum distance:
    • min. 20km @0.35dB/km
  • Supply voltage:
    • 8..30V DC
  • Current consumption:
    • typ. 30mA @ 12V DC
  • Supply connection:
    • Plug-in screw terminal, 5.08mm spacing
    • Labeled “L+” and “M”
  • Displays:
    • 8x LED inputs
    • 8x LED outputs
    • 1x LED Link
    • 1x LED Power

Housing and other data:

  • Housing:
    • Plastic housing for top hat rail installation
    • 105 x 45 x 75mm (L x W x H)
  • Enclosure rating:
    • IP20
  • Weight:
    • approx. 300g
  • Ambient temperature:
    • Storage: -40..+70°C, Operation: 0..+70°C
  • Permissible relative humidity:
    • 5..90% relative humidity (non-condensing)
  • Life expectancy:
    • > 25 years at 25°C ambient temperature
  • Scope of delivery:
    • 2 Converters Digital-I/O <> Single-Mode Glass Fiber
    • If needed please order power supplies as separate accessories
Weight 0.2 kg