What this MCCB carries and what it doesn't
The Siemens 3VA2340-6HL32-0CA0 is a SENTRON molded case circuit breaker rated for 400 A continuous current at 40 °C ambient, with a 3-pole line-protection configuration. The ETU320 electronic trip unit handles the overcurrent release; there's no ground-fault monitoring, no communication module, and no auxiliary contact built in. What it does include is an undervoltage release (UVR) — the integrated auxiliary trip is order code 3VA9608-0BB24, and the basic switch variant is 3VA2340-6HL32-0AA0.
Breaking capacity — what the ratings mean for panel coordination
This MCCB delivers 242 kA at 240 V, 187 kA at 415 V and at 440 V, 121 kA at 500 V, and 40 kA at 690 V. Those are the interrupting ratings at each voltage level — they tell you the maximum fault current the breaker can safely clear without welding contacts or rupturing the case. For a 400 A frame, the 187 kA at 415 V is the number most panel designers will check first for main or feeder duty in a low-voltage switchboard. The 40 kA at 690 V keeps it viable for 690 V industrial grids, though the 400 A continuous rating is the practical limit for that voltage class.
Thermal derating — the real current you get above 50 °C
The 400 A rating holds flat from 40 °C through 50 °C. Above that it drops: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If your panel internal ambient runs at 60 °C — common in a packed enclosure with upstream devices — you're looking at 370 A available, not the nameplate 400 A. That derating curve is the one that governs real-world sizing, not the catalog headline.
Physical fit and panel integration
Dimensions are 248 mm high, 138 mm wide, 110 mm deep.