400 A MCCB with motor protection — what the ratings mean for fit
The Siemens SENTRON 3VA2440-5MN32-0AH0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling, which simplifies panel thermal budgeting in warm enclosures. Breaking capacity is 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 9 kA at 690 V — the 415 V figure is the one most European industrial panels will reference for fault-current coordination studies. Designed specifically for motor protection, it includes phase failure detection and a trip indicator, with a configurable short-time delay adjustable between 4 s and 17 s to ride through motor starting inrush without nuisance tripping.
Integration and mounting dimensions
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep — the 110 mm depth is a key check for shallow backpanel enclosures where gland-plate clearance is tight. The auxiliary switch block is factory-configured as 2 auxiliary switches plus 1 trip alarm switch HQ, which covers status feedback and remote trip indication without adding a separate module. Maximum power loss at full rated load is 63.5 W — factor this into enclosure ventilation calculations, especially in multi-breaker panels.