The 5SY4425-8: The D curve targets loads with high inrush current — motor starters, transformer primaries, and solenoid banks — delaying trip above the nominal during start-up.
Sourcing & lifecycle
The 5SY4425-8 is classified as current production — no last-time-buy window or end-of-life notice. It remains a standard line item, orderable through normal Siemens distribution with no supply constraint. For a critical-spare holding, one in the cabinet covers the 4-pole 25 A D-curve slot common to many European-derived panels.
Integration & derating
The breaker occupies 4 modular width units (72 mm wide) and mounts in any position. Depth is 76 mm behind the panel, plus 90 mm height with combined top and bottom terminals. Rated for overvoltage category III, pollution degree 3, and IP20 with conductors connected. Sealable, halogen-free, and silicon-free construction suits cleanroom-adjacent or hygiene-conscious installations.