The Siemens 3VM1220-5EE46-0AA2 is a 4-pole molded-case circuit breaker in the 3VM1 IEC frame 250 series, rated for a breaking capacity of 55 kA at 415 V AC — class M (medium) per IEC 60947-2. It carries a TM220 thermal-magnetic trip unit with a fixed rating of In = 200 A, adjustable overload protection Ir from 140 A to 200 A, and a fixed short-circuit pickup Ii = 10 × In (2000 A). The neutral conductor is unprotected; terminal connection is standard.
What the ratings mean for the panel
The 55 kA Icu at 415 V tells you this breaker can safely interrupt a fault current up to that level without welding or rupturing — critical for high-capacity distribution panels where the prospective short-circuit current exceeds 25 kA. The adjustable Ir (140–200 A) lets you match the continuous current to the downstream cable or busbar rating without swapping the trip unit. The fixed Ii at 10× In means magnetic trips start at 2000 A; that's a typical setting for motor-starting inrush or transformer energization, but verify it doesn't overlap with your load's peak inrush if you have large drives.