What it is and what it does
The 3VA2340-5HL42-0AF0: Rated breaking capacity reaches 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. That means it can safely interrupt fault currents up to those levels without upstream cascading — critical for high-fault panels near transformers or large drives. Thermal derating is published: full 400 A holds through 50 °C, then drops to 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If your panel ambient runs above 50 °C, size the breaker for the derated figure, not the nameplate.
Physical fit and integration
Dimensions are 248 mm high, 184 mm wide, 110 mm deep. The 184 mm width is the standard 4-pole MCCB footprint for this frame — verify DIN-rail or screw-mount clearance in your enclosure before quoting. Built-in auxiliary contact configuration is 1 auxiliary switch + 1 trip alarm switch (HQ version). No undervoltage release, no shunt trip, no communication module, no ground-fault monitoring. If you need those, they must be added externally or the variant changed. The basic switch assembly is order code 3VA2340-5HL42-0AA0; the integrated auxiliary trip is 3VA9608-0BB11. These are the subcomponents if you are repairing rather than replacing the whole breaker.