The Siemens SENTRON 3VA2125-7KQ46-0AA0 is a 4-pole molded case circuit breaker rated for 25 A continuous current, designed for line protection in distribution panels. Its 330 kA interrupting capacity at 240 V handles high-fault scenarios typical of industrial mains, while the 242 kA rating at 415 V and 440 V covers common European and Asian line voltages. At 690 V the rating drops to 3.7 kA — still adequate for most motor branch circuits, but verify against your available fault current.
Key ratings and what they mean for fit
The 25 A continuous rating holds flat across the full -25 °C to 70 °C operating range — no derating needed for warm enclosures. The 800 V rated insulation voltage means it can be used on 690 V systems with margin. Ground-fault monitoring uses summation current formation on L+N conductors, which simplifies wiring compared to separate CT-based schemes. Communication function is built in, so it can report status to a BMS or PLC without an add-on module.
Dimensions and panel fit
At 86 mm deep, 140 mm wide, and 181 mm tall, this breaker fits standard MCCB panel cutouts. The 140 mm width means it occupies two adjacent 70 mm DIN-rail slots or a dedicated MCCB mounting plate. Plan for the 0.6 W maximum power loss — negligible for thermal budgeting even in a sealed enclosure.