Since 2003, the research topic "Optical-electrical combination conductor for monitoring electrical equipment for the occurrence of arcing faults and for information transmission in optical form with a combined electrical path to the power supply" has played an important role in research at the FHN. The university was granted a German patent for this invention in 2004, followed by international patent applications. Matthias Viehmann and Dipl.-Chem. Christina Kloß have created the conditions for testing the first sample arrangements. The simplest version of the combination conductor consists of a stranded copper wire surrounded by an optically transparent, electrically insulating and flexible sheath. This makes it possible to transmit electrical energy via the copper wire and light via the sheath. One end of the combination conductor is terminated with an electronic converter module, which converts the light into electrical signals. This makes it possible, for example, to detect arcing between the copper wire and its surroundings by coupling the light pulse it emits into the conductor sheath and the transducer converting this light pulse into an electrical signal. This "arc present" signal can be used to switch off the circuit affected by the arc fault. This application is particularly important, for example, in on-board networks of road and rail vehicles as well as in aeroplanes. This application was successfully simulated and tested back in 2005. On 10 January 2006, Prof. Viehmann and his research assistant Ms Kloß succeeded for the first time in the world in transmitting optical signals and electrical energy simultaneously via the combination conductor. A combination conductor with stranded copper wire and a transparent elastomer sheath was used for this purpose. This was supplemented by an optical transmitter with laser diodes arranged in a ring and an optical receiver with photodiodes arranged in a ring. Rectangular signals were then transmitted via the optically conductive sheath. Prof Viehmann: "I was surprised that the optical transmission delivered extremely good reception signals. I had even estimated the influence of a relatively strong curvature in the combination conductor to be higher beforehand." Based on these experimental results, research on this invention will be continued. The main focus here will be on further reducing the optical attenuation in the optically conductive sheath and optimising the conductor properties overall. Together with co-operation partners from universities and industry, the project will be intensified in the coming years. The aim is to put the combination conductor to practical use. The August Kramer Institute at the University of Applied Sciences will play a key role in this. It is interesting to note that talks are already being held with interested licence holders.

We will be happy to answer any further questions you may have:

Prof. Dr.-Ing. Matthias Viehmann

Tel. 03631 420-336

Press release 05/2006