Conventional push-buttons or auxiliary contacts can be connected to 2 channels or 4 channels. The information of the contact enquiry can be used for activating ABB-free@home® actuators or for recording status information. The contact polling voltage is made available from the binary input itself. Extension of the connecting cables possible by a maximum of 10 m. Flush-mounted device for installation in a 60 mm device box or distribution box. The bus can be connected via enclosed terminal block.