Electrotechnical and electronic apparatus and components, included in class 9, in particular switching apparatus, relays, switches and key buttons for the potential adjustment of bit-parallel status signals; analogue electronic circuits for converting analogue control, status and measuring signals at various signal levels; electronic circuits for converting bit-parallel, analogue and digital control, status and measuring signals into digital signals, including in particular in communications protocols for bus systems, including Can, DeviceNet, Profibus and Ethernet; electronic circuits for further processing various input signals into various output signals for automation purposes.;