For Sinumerik 828D (which uses a proprietary Siemens CF card), the software image is not publicly downloadable . You must order a replacement CF card from Siemens using the device serial number. The same applies to the “Solution Line” 828D.
Retrieve the matching License Key via the Web License Manager. Sinumerik Solution Line Download
If you lose your key or upgrade your software, you can use the Siemens Web License Manager. By entering the serial number of your CF card, you can "download" your existing license keys or assign new ones. Important Safety and Installation Tips For Sinumerik 828D (which uses a proprietary Siemens
Never attempt a software update without a complete NCK/PLC archive and a ghost image of the CF card. Sinumerik Solution Line Download