What the interrupting ratings mean for panel coordination
The Siemens 3VA2440-7HN42-0AA0 is a 4-pole SENTRON molded case circuit breaker rated 400 A continuous at 40 °C through 70 °C — no derating needed across that full band, which simplifies panel layout when ambient runs high. The interrupting ratings climb to 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 9 kA at 690 V. Those numbers govern series-coordination headroom with downstream breakers: at 415 V the 242 kA SCCR covers most industrial main or feeder applications without requiring a current-limiting upstream device. The 5 kA limited-to-1-second rating is the short-time withstand for selective coordination — if your scheme relies on intentional delay, that is the window.
Trip unit and N-conductor protection
The overcurrent release is the ETU350 electronic trip unit — adjustability for the N-conductor protection is selectable OFF, 50%, or 100% of the phase rating. That matters when the neutral is undersized or when you want full protection on a 100%-rated neutral. The 3VA2440-7HN42-0AA0 is designated for line protection; it does not carry a voltage-trip or undervoltage release, nor communication functions or ground-fault monitoring. If you need those, the ETU350 platform supports them on other variants, but this order code is a straight feeder breaker.
Physical fit and panel integration
Dimensions: 110 mm depth, 184 mm width, 248 mm height. That is a 4-pole frame sized for a standard MCCB cubicle or distribution panel — the width matches typical 4-pole SENTRON footprints, so a panel cut-out or bus-bar layout designed for a 3VA2 4-pole breaker will accept this unit without rework. IP40 on the front (finger-safe), no trip indicator, no undervoltage release coil. Storage range -40 °C to 80 °C; operating -25 °C to 70 °C. Maximum power loss 63.5 W — budget that as heat in the enclosure.