Siemens 56 program digital time switch 230v ac multi languages siemens 7lf4941 0 the siemens 7lf4941 0 is a usb adaptor and software for siemens digital switches 7lf4521 0 order code 55 7231 and 7lf4522 0 order code 55 7232 the adaptor allows simple program creation for siemens timer clocks with the help of a pc siemens 7lf4941 0 usb adaptor and software for siemens timer clock profi