The C25B34V250 is a Schneider Electric ComPacT NSX earth leakage circuit breaker with a MicroLogic 4.2 electronic trip unit rated 250 A at 40 °C. It delivers 25 kA Icu breaking capacity at 415 V AC (40 kA at 240 V AC), making it a fit for distribution panels where earth-leakage protection is integrated into the breaker — no separate RCCB needed.
The 250 A rating at 40 °C is the continuous current the breaker carries without tripping — sized for a feeder or main in a 250 A bus. The earth-leakage function is integrated, so you save a DIN-rail slot compared to a separate residual-current device. Breaking capacity of 25 kA Icu at 415 V AC means the breaker can safely interrupt a fault current up to 25,000 A without welding its contacts — sufficient for most industrial distribution boards with a transformer upstream. At 240 V AC it handles 40 kA Icu, which covers high-fault panels in North American 240 V systems.
This part is listed as current production (active lifecycle). No official successor exists; the ComPacT NSX range is still the active platform for this class.