What it is and what the ratings mean for your panel
The Siemens 3VM1450-4GE42-0AA0 is a 4-pole molded case circuit breaker from the SENTRON 3VM1 family, IEC frame 630, rated 500 A continuous with a TM220 ATFM thermal-magnetic trip unit. The 36 kA breaking capacity at 415 V (class N) means it can safely interrupt a fault current up to that level without welding contacts or cascading failure upstream — sized for industrial distribution panels where the available fault current is known to be under that threshold. The TM220 trip gives you adjustable overload protection (Ir = 350 A to 500 A) and a fixed short-circuit pickup of 10 × In (5,000 A), plus integral N-conductor protection. Mounts on a standard DIN rail or panel base; the 261 × 208 × 170 mm package fits a typical 4-pole MCCB slot in a SENTRON distribution board.
Integration notes for the panel builder
Rated for 50/60 Hz networks. The adjustable Ir band (350-500 A) lets you match the breaker to the actual load without swapping trip units — set it via the dial on the front face. The fixed Ii = 10 × In gives a flat short-circuit pickup; if your system needs selectivity with downstream breakers, verify the instantaneous threshold against the let-through of the next device. N-conductor protection is integral, so no separate neutral protection module is needed on a 4-wire system. The 100% nut keeper kit is included for secure busbar connections.