Siemens SENTRON 3VA2340-6HL32-0JC0 — 400 A MCCB with High Interrupting Capacity
The Siemens SENTRON 3VA2340-6HL32-0JC0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current at 40 °C, designed for line protection in industrial power distribution panels. Its interrupting capacity reaches 242 kA at 240 V and 187 kA at 415 V, meaning it can safely clear high-fault currents on large transformers or busway feeds without upstream coordination issues. The breaker carries a shunt trip (STL) and two auxiliary switches (HQ) factory-installed, so it integrates directly into emergency-stop or remote-trip circuits without additional accessory wiring.
Current Rating and Thermal Derating
The 400 A continuous rating holds from 40 °C through 50 °C ambient — no derating needed in a typical 50 °C panel interior. Above that, the breaker steps down: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If the panel ambient runs at 60 °C, the load must be capped at 370 A, not the nameplate 400 A. Maximum power loss is 96 W, which matters for enclosure heat calculations in sealed or high-fill-factor cabinets.
Interrupting Capacity Across Voltages
This MCCB delivers 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V. The steep drop at 690 V reflects the physical limits of the arc-extinction chamber at higher system voltages — on a 690 V line, the available fault current must stay under 7.5 kA. For most 400 V-class industrial systems (415 V or 440 V), the 187 kA rating covers nearly any transformer secondary or busway fault scenario.
Physical Fit and Panel Integration
Dimensions are 248 mm high, 138 mm wide, 110 mm deep. The 138 mm width fits standard 3-pole MCCB mounting footprints on a DIN rail or panel-mount base. Depth of 110 mm leaves clearance for rear-connected bus bars or cable lugs in a typical 400 mm-deep enclosure. No trip indicator is fitted — fault status comes from the auxiliary switch contacts wired to a PLC or annunciator.