SENTRON 3VA2440-6HL32-0JL0 — 400 A MCCB for high-fault line protection
The Siemens SENTRON 3VA2440-6HL32-0JL0 is a 3-pole molded case circuit breaker rated for 400 A continuous current across its full ambient range from 40 °C to 70 °C — meaning no derating needed in a warm enclosure or near other heat sources on the DIN rail. Its interrupting capacity hits 242 kA at 240 VAC and 187 kA at 415 VAC, so it handles the kind of fault current you see on large transformer secondaries or busway drops without needing an upstream current-limiting fuse. Designed for line protection, this MCCB carries a shunt trip (STL) release and a full auxiliary switch set: two auxiliary switches plus a trip alarm and an electrical alarm switch — enough for remote status and emergency trip back to a PLC or safety relay.
What the interrupting ratings mean on a real panel
At 500 VAC the breaker still interrupts 121 kA, which covers most 480 V distribution in industrial plants; at 690 VAC it drops to 9 kA, so on a 690 V line you need to verify the available fault current is under that threshold — common in mining or marine installations where the transformer impedance limits the fault. The 63.5 W maximum power loss at rated current matters for panel cooling — if you're packing several of these in a sealed enclosure, that heat adds up and may push your ambient above the 70 °C operating max. Dimensions are 248 mm high, 138 mm wide, 110 mm deep — a standard SENTRON 3VA footprint that drops into existing Siemens switchboard cutouts and busbar systems without panel rework.