In the precision body shop, Audi uses two laser welding cabins. When the production plants were planned, this reliable and tested technology was deliberately chosen. Following the positive experience with optic fiber technology for the A3 body construction, fiber optic technology was also chosen for INTERBUS networking in the Audi TT control system. The already familiar absolute immunity to interference, especially in areas highly succeptable to electromagnetic interference, such as precision body construction, was once again the main reason for choosing this technology.

20 Simatic S5 135 U controllers and 53 Simatic S5 95U are responsible for the control technology in the body shop. More than 50,000 I/O nodes are networked via INTERBUS. Data is transferred between the Simatic S5-135 Us via INTERBUS gateways, which link up to 10 I/O words bidirectionally. The miniature controllers and the 40 Kuka VRS1B robot controllers are connected via INTERBUS slave cards, which also transfer up to 10 I/O words bidirectionally to the PLC master. 30 SWAC operator terminals are distributed in the system as interfaces between man and machine; they are also networked with INTERBUS fiber optic technology.