400 A MCCB with a wide interrupting-capacity envelope
The Siemens 3VA2340-5KP32-0BA0 is a SENTRON 3VA2 molded case circuit breaker rated for 400 A continuous current across a 3-pole configuration, designed for line-protection duty in distribution panels and industrial switchboards.
Interrupting capacity — what the voltage columns tell you
This breaker delivers 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. The steep drop above 500 V means the 690 V rating governs any high-voltage bus application; for most 400 V-class industrial feeds the 121 kA figure provides substantial fault-current headroom.
Thermal derating — the real current you can carry
The 400 A rating holds at ambient temperatures up to 50 °C. Above that, the breaker derates linearly: 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C. If the panel ambient runs above 50 °C, size the continuous load against the derated figure, not the nameplate.
Physical fit and panel integration
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep — a 3-pole frame that fits standard MCCB mounting footprints in switchboards and panelboards. The 138 mm width matches the common 3-pole molded-case breaker slot; verify the bus-bar drilling pattern against the existing panel cutout.