What this MCCB delivers — and what the ratings mean for your panel
The Siemens SENTRON 3VA1125-5ED26-0AA0 is a 2-pole molded case circuit breaker (MCCB) rated 25 A at 40 °C, with a TM210 thermal-magnetic release. The 187 kA breaking capacity at 240 V AC and 121 kA at 415 V AC means it can safely interrupt very high fault currents without upstream cascading — critical for main or sub-feed protection in high-available-fault installations. The 25 A rating holds steady up to 50 °C; above that it derates slightly to 24 A at 55–60 °C and 23 A at 65–70 °C, so if your panel runs hot, you need to account for that thermal curve. With a rated insulation voltage of 500 V and operating voltage up to 415 V AC / 250 V DC, this MCCB fits standard 400 V three-phase and 240 V split-phase panels. The IP40 front protection keeps dust and tools out of the breaker face, but the body is not sealed — mount inside a suitable enclosure for washdown or outdoor duty.
Mounting and panel fit
The 3VA1125-5ED26-0AA0 measures 70 mm deep, 50.8 mm wide, and 130 mm tall. The 2-pole width (50.8 mm) matches the standard 2-module DIN-rail footprint — no surprises when laying out a distribution board. Depth of 70 mm leaves room for wiring behind the breaker in a standard 200 mm enclosure.