What this circuit breaker does on the line
The Siemens SIRIUS 3RV2021-4BA25-ZW97 is a motor protection circuit breaker with Class 10 trip and phase failure detection. Rated breaking capacity at 400 V is 25 kA, which is the maximum prospective fault current it can safely interrupt at that voltage. On a 480 V system the same breaker is rated 20 A continuous with a 100 kA interrupting rating at 240 V — the voltage-dependent curve is typical for this class. The unit mounts on a 35 mm DIN rail per DIN EN 60715, either snapped on or screwed, in any orientation.
Sourcing and lifecycle
This order code is listed as current production. Sourced and quoted to order against an RFQ through independent distribution.
Panel fit and wiring
The 3RV2021-4BA25-ZW97 occupies 45 mm width on the DIN rail, which is roughly 2.5 modular units (18 mm per TE). Depth of 97 mm and height of 119 mm leave clearance for spring-loaded terminal wiring — the main circuit terminals accept 2 × (0.5 to 2.5 mm²) solid or stranded. Keep 50 mm free above and below the breaker for airflow and tool access; side clearance of 30 mm prevents arc flash between adjacent devices. Operating temperature range is -20 to +60 °C; storage range -50 to +80 °C.