Transformer-protection circuit breaker, 4 A, Class 10
The thermal overload release handles sustained overcurrents, while the magnetic short-circuit trip clears faults fast. The Class 10 trip class means it can ride through transformer inrush without nuisance tripping — that's the whole point of this variant. Rated for 690 V and 50/60 Hz, it fits into the S00 frame size, which is the most compact in the SIRIUS family for this current range.
Any mounting position is allowed, so it'll fit in tight spots as long as those clearance zones are respected.
