Mechanical fit and panel slot allocation
The 3RK1901-3GA00 occupies 45 mm on the DIN rail — that's the slot width you need to reserve in the panel layout for this AS-Interface support module. It mounts specifically on the SIRIUS 3RA19 22-1A standard rail adapter, so the mechanical integration path is locked to that adapter plate — no direct DIN-rail clip, no alternative mounting bracket.
Functional role in the AS-Interface network
This module provides mechanical and electrical support for an AS-Interface load feeder module — it's the carrier and bus interface for the feeder, not a standalone I/O slice. The 45 mm width matches the standard mounting rail plate footprint used across the SIRIUS 3RA19 family, so panel cutouts and wiring ducts stay consistent.
Lifecycle and sourcing posture
Listed at current lifecycle stage — Siemens has not flagged this for discontinuation, so it remains a valid BOM line for new builds and MRO spares alike.