What this MCCB carries for a panel build
The Siemens 3VA1180-5EF36-0KH0 is a 3-pole SENTRON molded case circuit breaker rated 80 A at 40 °C, with a 187 kA interrupting capacity at 240 V — that figure drops to 121 kA at 415 V and 75.6 kA at 440 V, so for a 480 V panel you are working with the 415 V curve. Power loss runs 19.2 W max, which matters for thermal coordination inside a sealed enclosure.
Thermal derating and ambient range
At 55 °C it derates to 78 A, at 60 °C to 77 A, at 65 °C to 75 A, and at 70 °C to 74 A. For a panel that sees 55 °C internal air, the continuous load must stay under 78 A — the spec table gives the exact curve, no guessing.