The Siemens 3VA1332-4EE42-0AA0-ZD00 is a 4-pole IEC frame 400 molded case circuit breaker rated 320 A continuous, with a breaking capacity of 36 kA at 415 V (class S). The thermal-magnetic TM220 trip unit gives adjustable overload protection (Ir = 224 A to 320 A) and a fixed short-circuit pickup at Ii = 10 × In (3200 A). The ATFM designation indicates it's line-protection oriented, not motor-protection. The N conductor is unprotected on this variant, which matters if you need full neutral protection in a 4-pole distribution board.
Mounts in a standard IEC frame 400 footprint with nut keeper kit included for DC Power OEM assembly. The 4-pole form factor fits a 4-module wide panel cutout. Torque the line and load terminals to the Siemens-specified value for the frame 400 (typically 35–40 N·m on the main lugs, but confirm with the installation instructions for this exact variant). The unprotected neutral bus bar must be sized for full neutral current if the load has harmonics or unbalanced phases.