DIN-rail base unit for SIMATIC remote I/O
The 3RK1908-0AP00-0DP0 is a SIMATIC BaseUnit — the mechanical and electrical backbone that a remote I/O module snaps onto. It takes 30 mm of DIN-rail width and stands 215 mm tall, with a 75 mm depth that leaves room behind the module for wiring fingers. Rated for 7 A maximum on the main current circuit, it carries three poles via push-in spring-loaded terminals — the same terminal type on the auxiliary and control side. The 24 VDC supply (20.4 V min, 28.8 V max) powers the base and the module above it.
Terminal and wiring detail
This is the 'without feed-in' variant, meaning it does not integrate a power bus pass-through — each base is individually wired for its supply. For a multi-drop string, you would use the feed-in version or add a separate power distribution block.
Vibration resistance is 2g up to 500 Hz (15 mm displacement below 6 Hz); shock is 6g for 11 ms. Pollution degree 2 — suitable for a typical control cabinet interior.