What it is and what it does
The Siemens SENTRON 3VA2340-7HL32-0AE0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current at 40 °C, designed for line protection in distribution panels. It carries a maximum breaking capacity of 330 kA at 240 V, 242 kA at 415 V, and 7.5 kA at 690 V — so it can interrupt high fault currents on the secondary side of a large transformer or at a main feeder. The 400 A frame holds its rating up to 50 °C; above that it derates to 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. That thermal curve matters if the breaker sits in a hot enclosure or near other heat sources — plan for the derated number, not the 400 A nameplate. It ships with four HQ auxiliary switches and no undervoltage release, no ground-fault monitoring, and no communication module. The basic switch version is order code 3VA2340-7HL32-0AA0. Storage range is -40 °C to 80 °C; operating range is -25 °C to 70 °C. Max power loss is 96 W — enough to factor into enclosure ventilation if the panel is tightly packed.
Panel fit and integration
The 3VA2340-7HL32-0AE0 measures 248 mm high, 138 mm wide, and 110 mm deep. It mounts on a DIN rail or bolts directly into a panel backplate. The 110 mm depth is shallow enough for standard 200 mm deep enclosures; the 138 mm width means it occupies three 45 mm pole spaces. Four HQ auxiliary switches are pre-installed — no need to order them separately. No undervoltage release or ground-fault module is fitted, so if the spec calls for those, this variant is not the one.