The Siemens 3RV1421-1JA10-ZW97 is a circuit breaker in the S0 frame size, specifically designed for transformer protection. It carries an A-release (overload) set at 7...10 A and an N-release (short-circuit) set at 208 A, with screw terminals and standard switching capacity. The unit is packaged in multi-unit packs of 14. The A-release range of 7...10 A means this breaker is sized for the inrush and thermal characteristics of a transformer primary, not a motor. The N-release at 208 A provides short-circuit protection coordinated to clear faults before the transformer winding is damaged.
For procurement planning, the 'current' status means the part is available through normal Siemens distribution channels. Pricing and lead time are confirmed at the time of quote against an RFQ.
The S0 frame size mounts on a standard DIN rail in a control panel. Screw terminals accept copper conductors typical for transformer primary circuits up to the rated current. The multi-unit packaging (14 per pack) suits OEM builds or panel shops stocking a common size.