Assessment and Acquisition of Siemens Library for QElectroTech (Open Source)
If you need high-precision technical symbols directly from Siemens, you can convert their official CAD data: i qelectrotech siemens library free
Missing: S7-300/400 legacy modules, ET200SP distributed IO details, SINAMICS S120, safety relays (3SK), exact terminal diagrams. ET200SP distributed IO details