Siemens digital output module sm 1223 series siemens 6es7223 1bh32 0xb0 the siemens 6es7223 1bh32 0xb0 is a din rail sm 1223 digital input output signal module that will convert the level of the external digital signals from the process into the internal signal level of the s7 1200 the digital signal can then be mixed as desired by the user to the relevant task siemens 6es7223 1bh32 0xb0 sm 1223 digital input output module