What this MCCB delivers for your line
The Siemens SENTRON 3VA1125-5EF36-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated 25 A at 40 °C, designed for line protection in distribution panels. Its TM240 thermal-magnetic release handles overloads and short-circuits, with a massive 187 kA breaking capacity at 240 V — enough to clear faults on high-available-current transformers without cascading upstream. That SCCR headroom means you can coordinate selectivity downstream without worrying about the main breaker opening on a remote fault, holding takt time on automated lines where every second of unplanned downtime costs thousands.
Breaking capacity — the number that decides coordination
Breaking capacity drops with voltage: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V. That 17 kA floor at 690 V still covers most industrial motor branch circuits. The rated insulation voltage of 800 V confirms this breaker is built for 690 V systems with margin. For DC applications, Siemens directs you to the 3VA device manual — the thermal-magnetic release is AC-optimized, so DC derating applies.
Thermal performance and panel fit
Current rating holds at 25 A from 40 °C up to 50 °C, then derates to 24 A at 55–60 °C and 23 A at 65–70 °C. That flat curve through 50 °C means you don't lose capacity in a warm enclosure. Power loss is 8.5 W maximum — negligible for heat budgeting in a packed panel. Dimensions are 130 mm high, 76.2 mm wide (3 inches), 70 mm deep. Front IP40 protection keeps out tools and fingers; the rear is open-frame for busbar connection. No undervoltage release, no trip indicator, no communication module — this is a straight line-protection breaker, no extras.