Motor protection MCCB with shunt trip — 500 A frame, 330 kA interrupting
The Siemens SENTRON 3VA2450-7MN32-0JC0 is a 3-pole molded case circuit breaker (MCCB) designed specifically for motor protection, rated 500 A at 40 °C and carrying a 330 kA interrupting capacity at 240 V. That interrupting rating drops to 242 kA at 415 V and 440 V, then to 187 kA at 500 V, and 15.3 kA at 690 V — so the SCCR headroom shrinks fast above 500 V; verify your available fault current at the point of common coupling before specifying. The breaker includes a shunt trip release (STL) and two auxiliary switches HQ, plus phase failure detection, making it suitable for remote trip and status feedback in motor control centers.
Current derating and thermal budget
Rated current holds flat at 500 A from 40 °C up to 50 °C, then derates to 495 A at 55 °C, 490 A at 60 °C, 485 A at 65 °C, and 480 A at 70 °C. Maximum power loss is 99 W. The operating temperature range is -25 °C to 70 °C; storage spans -40 °C to 80 °C. If the panel ambient runs above 50 °C, the derating curve governs — plan for a 20 A drop at 70 °C.
Dimensions and panel integration
The breaker measures 248 mm high, 138 mm wide, and 110 mm deep. Three-pole footprint fits standard SENTRON mounting patterns; the shunt trip and auxiliary switch block add depth behind the panel face. No undervoltage release is fitted, and no communication module is included — the only electrical accessories are the shunt trip and two HQ aux switches.