What this MCCB is and what it protects
The Siemens SENTRON 3VA2340-5KP32-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current, designed for line protection in low-voltage distribution. It carries interrupting ratings of 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 7.5 kA at 690 V — so at the common 400 V class it clears faults up to 121 kA without cascading upstream, which is the figure that governs selectivity coordination in a main or feeder breaker position.
Thermal derating and continuous current
The 400 A rating holds flat up to 50 °C ambient. Above that it derates: 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C. If your panel internal ambient runs above 50 °C — common in a crowded enclosure with other heat sources — the effective continuous current drops, so size the breaker for the actual operating temperature, not the nameplate.
Communication and auxiliary switching
This variant includes a communication function for integration into a monitored distribution system — useful for remote trip indication, load shedding, or energy management. It ships with two HP auxiliary switches for status feedback, but no undervoltage release and no ground-fault monitoring. The basic switch variant is 3VA2340-5KP32-0AA0.
Physical fit and environment
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep. It operates from -25 °C to 70 °C and stores from -40 °C to 80 °C. Maximum power loss is 96 W — account for that in your enclosure thermal budget.
Lifecycle and sourcing
The lifecycle stage is listed as current, meaning Siemens still actively manufactures and supports this order code. No phase-out or last-time-buy notice is available.