What the ratings mean for fit
The Siemens SENTRON 3VA2340-5HL32-0CA0 is a 3-pole molded case circuit breaker rated for 400 A continuous current at 40 °C — that is the full frame rating, not a derated value. The interrupting capacity hits 187 kA at 240 V, dropping to 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. For a 400 A frame, those numbers are high-end; the 187 kA at 240 V means it handles fault currents at the transformer secondary without needing a current-limiting fuse upstream. The ETU320 electronic trip unit gives adjustable long-time, short-time, and instantaneous protection — line protection version, so it is set for feeder duty, not motor start. Thermal derating is published stepwise: flat 400 A through 50 °C, then 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, 340 A at 70 °C. If your panel ambient runs 55 °C, you lose 15 A off the nameplate — plan the load accordingly. The 800 V rated insulation voltage (Ui) means it is safe for 690 V line-to-line systems, which matches the interrupting capacity curve. Mounts into a standard SENTRON 3VA panel footprint. Dimensions: 248 mm height, 138 mm width, 110 mm depth — no extra clearance needed for the undervoltage release (UVR) because it is integrated into the breaker body, not a bolt-on accessory. No auxiliary contacts, no communication module, no ground-fault monitoring on this variant; those are separate order codes if needed.
Lifecycle and sourcing reality
The integrated undervoltage release (UVR) is the 3VA9608-0BB24 — a separate orderable spare if the UVR coil fails. The basic switch (breaker without trip unit) is order code 3VA2340-5HL32-0AA0; the ETU320 release is built in on this variant. No phase-failure detection, no voltage trigger, no communication function — this is a straight feeder breaker, not a smart or communicating device.