What this MCCB carries and where it fits
The Siemens SENTRON 3VA2450-7MN32-0AJ0 is a 3-pole molded case circuit breaker (MCCB) designed specifically for motor protection. It is rated 500 A continuously at 40 °C, with the same rating holding through 50 °C before a gentle derate begins — 495 A at 55 °C, 490 A at 60 °C, 485 A at 65 °C, 480 A at 70 °C. That thermal profile means it can sit in a warm enclosure without losing headroom, which matters when the breaker shares a panel with drives or transformers. Breaking capacity is 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 15.3 kA at 690 V. The short-time withstand (Icw) is 6 kA limited to 1 second — that figure governs selectivity with downstream breakers during a fault. For motor starting duty, the adjustable time-delay settings (minimum 4 s, maximum 13 s) let you ride through inrush without nuisance trips. Phase failure detection is built in, and the auxiliary switch configuration includes two auxiliary switches plus one trip alarm switch HP. No undervoltage release or communication module is fitted from the factory — those are add-on options if the application needs them.
Mounting and integration into the panel
Dimensions are 248 mm high, 138 mm wide, 110 mm deep. The 138 mm width is the standard 3-pole MCCB footprint for this SENTRON frame size, so it drops into existing panel layouts without re-drilling the mounting plate. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C — cold-storage and freezer environments are within the operating envelope as long as the ambient stays above -25 °C. Maximum power loss is 99 W. That is the heat the breaker dissipates at full rated current — factor it into the enclosure thermal calculation, especially in a sealed NEMA 4X or IP65 cabinet where convection is limited.