What this MCCB delivers in the panel
The Siemens SENTRON 3VA1125-5EF36-0KA0 is a 3-pole molded case circuit breaker rated for 25 A continuous current (Iu) with a TM240 thermal-magnetic overcurrent release. Its interrupting capacity hits 187 kA at 240 V, 121 kA at 415 V, and 75.6 kA at 440 V — numbers that give selectivity headroom on a high-fault panel main or feeder. The 70 mm depth and 76.2 mm width fit standard DIN-rail or mounting-plate layouts; the IP40 front protection keeps incidental contact out. No auxiliary contacts or communication module are fitted on this variant, so any remote status or trip indication must come from the optional 3VA9688-0BL33 auxiliary trip block.
Thermal derating and ambient limits
This breaker carries its full 25 A rating from 40 °C through 50 °C ambient. At 55 °C it derates to 24 A, at 60 °C to 23.5 A, at 65 °C to 23 A, and at 70 °C to 22.5 A. The operating range spans -25 °C to 70 °C; storage can go from -40 °C to 80 °C. For a panel that runs warm — say, a densely packed line-up — the 55 °C derate point is where you size the load.