What this MCCB is and what it does
The Siemens SENTRON 3VA2340-6HL32-0BL0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current, designed for line protection in distribution panels and industrial switchboards. It carries a 242 kA breaking capacity at 240 V AC, dropping to 187 kA at 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V — the voltage-dependent interruption performance tells you exactly where this breaker can clear a fault without upstream coordination issues. The 400 A rating holds flat from 40 °C through 50 °C ambient, then derates 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 runs hot — say a non-ventilated enclosure near a furnace line — that derating curve is the one that governs real-world ampacity, not the nameplate 400 A.
Built-in auxiliary and release configuration
This variant ships with an undervoltage release (UVR) and a full auxiliary switch complement: 2 auxiliary switches, 1 trip alarm switch, and 1 electrical alarm switch (HQ type). That means it can signal its status to a PLC or annunciator without an external add-on module — useful for remote trip indication or safety interlock circuits that need to drop the breaker on loss of control voltage. The base switch variant is 3VA2340-6HL32-0AA0, so the -0BL0 suffix adds the UVR and the HQ alarm package on top of that core breaker. A trip indicator is present, giving a local mechanical flag when the breaker has tripped on fault.
Physical fit and environmental limits
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep — a standard 3-pole MCCB footprint that fits most DIN-rail or panel-mount enclosures designed for SENTRON 3VA2 breakers. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power loss at rated current is 98.5 W, which should be factored into enclosure thermal calculations.