MCCB for high-fault plant feeders
The Siemens SENTRON 3VA2440-6HL32-0AJ0 is a 3-pole molded case circuit breaker rated for 400 A continuous from 40 °C through 70 °C, with an adjustable thermal-magnetic trip range of 600 A to 4 800 A. It is designed for line protection — meaning it sits at the incoming feeder or large subfeed, not on a motor branch. The interrupting ratings are what make this part stand out: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 9 kA at 690 V. That SCCR headroom lets it serve as the main breaker in a high-fault plant distribution panel without cascading upstream.
What the ratings mean for fit
The 400 A continuous rating is flat across the 40–70 °C ambient range — no derating curve to chase in a warm enclosure. The adjustable trip band (600–4 800 A) lets you coordinate with downstream breakers without swapping the frame. The 242 kA at 240 V is the highest SCCR on record for this frame; at 690 V the same breaker drops to 9 kA, so if your line side is 690 V, verify the available fault current is under that threshold. Power loss is 63.5 W maximum — budget that heat in the panel thermal calculation.
Panel integration notes
Dimensions are 110 mm deep, 138 mm wide, 248 mm tall — a standard MCCB footprint for this current class. The 3-pole block mounts on a DIN rail or directly to a backplate via the screw terminals. The trip indicator is present; no communication function, ground-fault monitoring, or voltage-trip feature is built in. Verify the gland plate cutout accommodates the 138 mm width before laying out the panel.