Rated Current and Breaking Capacity
The Siemens 3VA2450-7MN32-0JH0 is a SENTRON molded case circuit breaker (MCCB) rated for 500 A continuous at 40 °C ambient, with no derating needed up to 50 °C — the full 500 A holds across that band. Above 50 °C the rating steps down linearly: 495 A at 55 °C, 490 A at 60 °C, 485 A at 65 °C, and 480 A at 70 °C. The interrupting capacity is 330 kA at 240 V AC, dropping to 242 kA at 415 V and 440 V, 187 kA at 500 V, and 15.3 kA at 690 V. That 330 kA at 240 V is the figure that governs fault-clearing in low-voltage distribution — it safely interrupts faults up to that level without cascading upstream, provided the available fault current at the panelboard doesn't exceed it.
Motor Protection Design and Auxiliary Functions
This MCCB is specifically designed for motor protection, with phase failure detection built in — it trips on loss of any phase, preventing single-phasing damage to the motor windings. The auxiliary switch configuration includes 2 auxiliary switches plus 1 trip alarm switch (HQ designation), and a shunt trip release (STL) is integrated for remote tripping. The trip indicator and voltage trigger are both present, giving visual and electrical confirmation of the breaker state. There is no undervoltage release and no communication module on this variant.
Physical Dimensions and Installation
The 3VA2450-7MN32-0JH0 measures 248 mm high, 138 mm wide, and 110 mm deep — a 3-pole frame that fits standard SENTRON panel cutouts. The depth of 110 mm (4.33 in) is the dimension to watch when planning gland-plate clearance or enclosure depth. Mounting is via the standard MCCB bolt-on or plug-in base; no DIN-rail adapter is used for this frame size.
Environmental and Electrical Ratings
Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power dissipation is 99 W at rated load — account for that heat in the enclosure thermal budget. The short-time withstand rating is limited to 6 kA for 1 second (the Icw figure for this frame).