The Siemens SENTRON 3VA2340-7HL32-0AL0 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. Its interrupting capacity hits 330 kA at 240 V AC — that's the short-circuit rating that governs fault clearance in low-voltage switchgear. At 415 V and 440 V it still holds 242 kA, dropping to 187 kA at 500 V and 7.5 kA at 690 V. The 400 A rating is flat through 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 derating curve matters if the breaker sits in a warm cabinet or next to other heat sources — the 400 A nameplate only holds below 50 °C ambient.
Dimensions and panel fit
The breaker measures 248 mm high, 138 mm wide, and 110 mm deep. That 110 mm depth (4.33 in) is the key number for enclosure depth — it tells you whether this MCCB clears the gland plate or backplate without a spacer. Width at 138 mm (5.43 in) governs the DIN-rail or mounting-plate footprint; three poles at that width means the phase spacing is fixed. The 248 mm height (9.76 in) plus the lug/terminal projection determines the vertical clearance in the panel.
Auxiliary switching and monitoring
This variant ships with 2 auxiliary switches, 1 trip alarm switch, and 1 electrical alarm switch (HQ configuration). The trip indicator is present — a visual flag that confirms the breaker tripped on fault rather than being manually opened. No undervoltage release, no ground-fault monitoring, no communication module on this build. Power loss at full rating is 96 W maximum, which factors into the cabinet thermal budget.
Environmental limits
Operating temperature range is -25 °C to +70 °C. Storage range is wider at -40 °C to +80 °C — that storage ceiling is the handling limit, not the running limit. The breaker is rated for indoor use in a controlled environment; no IP rating is listed, so it expects a clean, dry enclosure.