What this MCCB brings to a panel
The Siemens 3VA1125-5EF36-0DC0 is a SENTRON molded case circuit breaker sized for line protection in distribution panels. Rated 25 A continuous at 40 °C, it holds that full rating through 50 °C before a gentle derate begins — 24 A at 55 °C, 23 A at 70 °C — which buys headroom in a warm enclosure without upsizing the frame. The 187 kA interrupting capacity at 240 V tells you this breaker can sit upstream of a high-fault service entrance and still clear a bolted fault without venting or cascading. At 415 V it still interrupts 121 kA; at 690 V it holds 17 kA. That kind of SCCR muscle means it's suited for industrial mains where transformer capacity is large and fault current runs high. Three poles, no communication module, no ground-fault monitoring — this is a straight line-protection MCCB with an undervoltage release (UVR) built into the auxiliary release slot. The UVR drops the breaker if control voltage falls below the dropout threshold, which is standard for emergency-stop circuits or mains-disconnect schemes where loss of control power should kill the load. The auxiliary switch complement is two HQ (high-accuracy) form-C contacts, enough to signal breaker status back to a PLC or annunciator without an add-on module.
Panel fit and footprint
The 3VA1125-5EF36-0DC0 measures 76.2 mm wide, 130 mm tall, and 70 mm deep — a 3-pole frame that fits standard DIN-rail or panel-mount cutouts in SENTRON distribution boards. The 70 mm depth is shallow enough to clear a 120 mm deep enclosure back wall with room for wiring gutters. Power loss is 11 W maximum at rated load, so thermal rise inside a sealed cabinet is manageable; group several of these in a row and the cumulative heat still stays within the derate curve if ambient is kept under 50 °C.