Siemens 5WG1420-3AB11 Brand Introduction Siemens 5WG1420-3AB11 belongs to KNX/EIB Instabus series binary input module, developed for building automation control system. It specializes in collecting dry contact digital signals from switches, push buttons and window/door contact sensors, converting field switch signals into KNX bus telegrams for building lighting, shutter and HVAC logic control.