The Siemens SENTRON 3VA2340-6HN32-0BC0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current at 40 °C, designed for line protection in industrial distribution panels. Its 242 kA breaking capacity at 240 V AC means it can safely interrupt a fault current up to that level without upstream fuses needing to clear — critical for high-fault installations like transformer secondaries or large motor control centers.
Breaking capacity and thermal derating
At 415 V AC the interrupting rating is 187 kA, dropping to 121 kA at 500 V and 7.5 kA at 690 V — the high 240 V rating is what sets this frame apart for North American 480Y/277 V services where the line-to-neutral fault can reach 200 kA+. The 400 A continuous rating holds flat to 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. If your panel ambient runs over 50 °C, size the load side accordingly.
Built-in accessories and footprint
This MCCB ships with an undervoltage release (UVR) and two HQ auxiliary switches pre-installed — no separate add-on modules to order or wire. The UVR drops the breaker on loss of control voltage, a common requirement for emergency-stop chains and safety circuits. Dimensions are 248 mm high, 138 mm wide, 110 mm deep, fitting standard Siemens SENTRON mounting patterns. The 3-pole unit occupies the same footprint as other 3VA2 frames, so panel cutouts stay consistent across ratings.