The Siemens SENTRON 3VA1580-5EF32-0HL0 is a 3-pole molded case circuit breaker rated for 800 A continuous current at 40 °C, with a breaking capacity of 121 kA at 415 V. At 240 V the interrupting rating rises to 187 kA, and at 690 V it still holds 52.5 kA, so it handles high-fault-current service entrances and transformer secondaries without cascading.
Above that it derates: 780 A at 55 °C, 761 A at 60 °C, 741 A at 65 °C, and 722 A at 70 °C. If your panel ambient runs toward 60 °C — common in tightly packed switchgear or near a furnace line — you lose about 5% of the headline rating. The maximum power loss is 240 W, so ventilation or spacing in the enclosure matters; a sealed cabinet with no airflow will push internal temperature above the free-air rating.
Physical fit and auxiliary configuration
A shunt trip release (STL) is installed for remote tripping.