What this breaker is and what the ratings mean
The Siemens 3VA1140-6EF32-0AA0-ZD00 is a 3-pole IEC frame 160 molded-case circuit breaker with a 70 kA interrupting capacity at 415 V (breaking capacity class H). That 70 kA rating means it can safely clear a fault current up to that level without rupturing — critical for high-fault installations close to the transformer or in a distribution switchboard where available fault current is high. The thermal-magnetic trip unit is a TM240 ATAM, set at In = 40 A, with adjustable overload protection (Ir) from 28 A to 40 A and fixed short-circuit protection (Ii) at 5 to 10 times In. The Ir adjustment lets you fine-tune the continuous current rating to match the downstream cable or load without swapping the breaker body. This variant includes a nut keeper kit and is designated for a DC Power OEM in China — the nut keeper prevents hardware loosening under vibration in power-conversion cabinets. The breaker itself is standard 3VA1 platform, so it mounts in the same Siemens panelboard and distribution board footprints as other 3VA frame-160 units.