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Plastic-Fiber Optic Interface  RS232

Plastic-Fiber Optic Interface RS232

Configuration compatible with 9-pin PC interfaces - transmission distance 5 to 80 meters.


PC connection over fiber-optic cables

Background knowledge: Power for the interfaces
The interface type described on this page is powered from the signal lines of the serial interface and generally requires no external power supply to operate on standard RS232 interfaces.

If however there are supply problems due to low-power interfaces, it is always possible to externally power the interface with up to 9V using its handshake inputs, or to use fiber-optic interfaces having their own power supply (e.g. model 81201).

With model 81029 there is also a 9-pin special version available whose transmission distance is limited to from 0 to 20m, but which only places an approx. 2mA load on the connected RS232 interface. With this version it is also possible to run on lower power RS232 interfaces without the need for an additional voltage source.


Background knowledge: Transmission distances
The limitation with respect to a minimum required fiber optic cable length of 5 meters is only relevant when using the maximum baud rate of 115.200 baud while simultaneously running the interfaces on RS232 ports with low output voltages.

If any of these limiting conditions does not apply, the Interfaces (e.g. for galvanic isolation of serial ports) can also be operated using very short fiber optic cable lengths.

Due to the current-saving construction of model 81029 we recommend in such application cases still using this Interface type, since the connected RS232 ports are only minimally loaded.


Product properties:

  • Conversion from RS232 to fiber-optic cable
  • Transmission distance 5 to 80 meters
  • Easier installed than any copper cable, thanks to patented FOC adapter
  • The interface is very easy to install:
    • Cut the fiber-optic cable with a sharp knife at right angles.
    • Insert into patented adapter of the W&T interface.
    • Plug the adapter into the PC.
    • That’s it!
  • 100% protection against interfering radiation
  • No re-configuration of transmission parameters required
  • Electrical isolation
  • Lightning protection
  • Conforms to standards both in office and industrial environments:
    • Increased noise immunity for industrial areas
    • Stricter noise emission for residential and commercial areas


Baud rate:   110..115,200 baud
Data format:   any format
Signal lines:   RxD, TxD (full duplex)
Transmission distance:   typically 5..80 meters
(Specifications for maximum transmission distance
when operating on RS232 ports
with MC1488 driver chips
and with handshake lines connected)
Power supply:   Generally from the RS232 signals
For low-power versions of the
RS232 interface external supplying of the
interfaces via handshake inputs
with up to 9V DC is possible
RS232 adapter:   9-pin SUB-D socket for PC
Fiber-optic cable adapter:   integrated socket with automatic
interlocking of the fiber-optic cable
Fiber-optic medium:   Duplex plastic optical fiber cable
Dimensions 2.2 x 4.4 mm
with a fiber diameter of 1 mm
Material: core: PMMA, cladding: PE
Wavelength:   approx. 660 nm
Ambient temperature:   Storage: -40..+70°C
Operation: 0..+50°C
Housing:   SUB-D adapter housing
Weight:   approx. 30 g
Delivery:   1x FOC RS232 interface, 9-pin for PC




Send messages - when limits are violated or timer-based - for informational purposes directly to the responsible technical as an e-mail or as a reroute via SMS.


After the device has been configured for and connected to your network, the following steps are still necessary.

Open the profile for configuring e-mail alarm messages. e-57606-35-pide-000
Enter the desired parameters. e-57606-36-pide-000
When the limit you have set is exceeded, the device sends an e-mail which can also be transmitted as an SMS message using special functions available from cellular phone service providers. e-57606-37-piww-000