Extension unit for mounting on all 15 SIMATIC 4:3 fully protected HMI devices, mounting to the right or left of the device The extension units for the 16:9 PRO devices are suitable for the flexible installation of control elements such as emergency stop, selector switches, illuminated pushbuttons, key switches, indicator lights or RFID readers, which easily and individually expand the operating options on site. They are coordinated with the design of the PRO devices and are installed underneath the device. The extension units are available for individual assembly and are therefore easy to retrofit. Thanks to the pre-punched cutouts for the installation locations on the inner side, the extension units can be adapted to any application quickly and conveniently on site. For greater flexibility, 3 different connection options can be selected for the PLC connection of the control elements: Hardwired, PROFINET and PROFISAFE. Accessories for SIMATIC HMI
