What it is and where it fits
The Siemens 6ES7470-1VB20 is a Videomat IV image analysis system for the S7-400 rack. It's a hardware real-time image processor in an adapter casing that connects up to three monochrome cameras. The system software is included with the unit.
Sourcing reality — spare part only
This part carries a mature lifecycle stage and is explicitly designated as available as a spare part only. That means Siemens no longer builds it for new installations — it's held for replacement of existing Videomat IV systems in the field. For a BOM line or a line-down repair, this is a quoted-to-order part sourced through the spare-parts channel. No direct successor order code is listed, so the replacement path is either this exact spare or a system-level migration off the Videomat IV platform.