The Siemens 3VA1340-5EF32-0AB0 is a 3-pole IEC frame 400 molded-case circuit breaker with a 55 kA interrupting capacity at 415 V (class M). It ships with a TM240 thermal-magnetic trip unit, rated In=400 A, adjustable overload Ir from 280 A to 400 A, and short-circuit pickup Ii adjustable 5 to 10 times In. Two built-in auxiliary changeover switches are included, plus a nut keeper kit for secure panel mounting.
The TM240 trip unit gives you a thermal curve for overloads and a magnetic instantaneous for shorts; the adjustable Ir (280–400 A) lets you fine-tune the continuous current to match the downstream load, not just the frame. The Ii range of 5–10× In (2,000–4,000 A) covers motor-start inrush or feeder protection without nuisance trips.
The 3-pole footprint fits a typical 400 A frame cutout; auxiliary switches are factory-installed, so no add-on module occupies adjacent DIN space. Verify gland-plate clearance for the line and load lugs — frame 400 breakers usually require 70–95 mm² cable terminations.