What this breaker is and where it fits
The Siemens SENTRON 3VA2440-6HL32-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous at up to 70 °C ambient — no derating needed across the full operating temperature band. It carries a 242 kA interrupting capacity at 240 V and 187 kA at 415/440 V, so it handles high-fault utility feeds and large transformer secondaries without cascading upstream. Designed for line protection (not motor or generator protection), it mounts in standard switchboard or panelboard enclosures; the 138 mm width and 248 mm height fit the 3VA modular footprint.
Breaking capacity — what the numbers mean for coordination
At 240 V the breaker clears 242 kA symmetrical; at 415/440 V it clears 187 kA; at 500 V it clears 121 kA; at 690 V it clears 9 kA. Those are the short-circuit current ratings (SCCR) at each voltage level — the maximum fault the breaker can safely interrupt without welding contacts or rupturing the case. For a 400 A frame, 242 kA at 240 V is well into current-limiting territory, which means downstream components see less let-through energy. The 9 kA at 690 V is the ceiling for 690 V line-side faults; if your system runs 690 V with available fault current above that, you need a current-limiting fuse ahead of this breaker or a higher-rated frame.
Thermal performance — full rating across the panel ambient range
Rated 400 A from 40 °C through 70 °C ambient — no derating curve to apply. That simplifies panel design: the breaker delivers its nameplate current even in a crowded enclosure where internal temperature climbs. Maximum power loss is 63.5 W at rated load, which is the heat the enclosure must vent. Storage range spans -40 °C to 80 °C; operating range -25 °C to 70 °C.
Built-in auxiliary switching
Factory-fitted with 2 auxiliary switches HP (high-performance) — no separate add-on block needed for status feedback to a PLC or remote indication. No undervoltage release, no shunt trip, no ground-fault module on this variant (the order code suffix -0AB0 specifies the bare line-protection configuration). If you need those functions, they are available as field-installable accessories in the 3VA family.