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 whose maximum transmission distance is limited to 20 meters, but which only loads the connected RS232 interface with a current of approx. 2mA. With this version it is also possible to operate on less-powerful RS232 interfaces without having to connect a separate power source.