Dupline® is a versatile bus for Industrial Applications and Building Automation. The Dupline® field-bus concept represents innovative and lean technology in hardware elements and in the communication principle. Coding of the units is as easy as dialling a phone number. The data transfer is made with minimum of communication overhead. The low 1 kHz frequency allows signal transmission up to 10 km. High noise immunity, use of existing wires and free topology are further characteristics and advantages.