Rating and interrupting capacity — what the numbers mean for your panel
The Siemens SENTRON 3VA2325-6HL32-0AF0 is a 3-pole molded case circuit breaker (MCCB) rated for 250 A continuous current across the full ambient temperature range from 40 °C to 70 °C — no derating needed up to that ceiling, which simplifies panel thermal calculations for a crowded enclosure. Its interrupting capacity reaches 242 kA at 240 V and 187 kA at 415 V, then drops to 7.5 kA at 690 V — the high fault-current headroom at the lower voltages means this breaker can be placed close to the transformer secondary without needing a current-limiting upstream device, but at 690 V the 7.5 kA limit demands a coordination study if the available fault current exceeds that level. The design is for line protection (cable and busbar feeder protection), not motor or generator protection — the trip curve and accessory complement (1 auxiliary switch + 1 trip alarm switch HQ, no undervoltage release, no ground-fault monitoring) confirm it is intended for distribution duty, not machine-level short-circuit and overload backup.
Lifecycle and sourcing posture
The maximum power loss of 37.5 W at rated current should be factored into the enclosure thermal budget, particularly in a sealed or high-fill panel.
Panel fit and physical integration
The MCCB measures 138 mm wide by 248 mm high by 110 mm deep — the depth is the critical dimension for shallow backpanels or gland-plate clearance; verify the swing of the door-mounted rotary handle (if used) against the 110 mm projection plus handle travel. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The storage minimum is relevant if the breaker sits in an unheated warehouse before installation. A trip indicator is fitted — useful for remote visual status without opening the door.