Transformer Protection Circuit Breaker — 12.5 A, CLASS 10
Three-pole construction, screw-type terminals for the main and auxiliary circuits, and it fits a 45 mm wide DIN-rail footprint.
The interrupting rating drops as system voltage rises — 100 kA at 240 V and 400 V AC, 42 kA at 500 V, and 6 kA at 690 V AC.
Phase Failure Detection and Mounting
Built-in phase failure detection means the breaker will trip if one phase drops out — critical for a transformer that would otherwise single-phase and overheat the remaining windings. The front is IP20 finger-safe; the terminals are touch-protected as well. Shock-rated to 25g for 11 ms, which holds it on the rail through a vibration event in a substation or on a machine skid.