63 A MCCB with flat thermal derating and high interrupting capacity
The Siemens SENTRON 3VA2163-6HN36-0DA0 is a 3-pole molded case circuit breaker rated for a continuous current of 63 A, with the notable characteristic that it holds that full 63 A rating across the entire ambient temperature range from 40 °C up to 70 °C — no derating needed as the panel warms up, which simplifies panel design in enclosed or high-ambient installations. Its interrupting capacity is 242 kA at 240 V AC, dropping to 187 kA at 415 V and 440 V, 121 kA at 500 V, and 3.7 kA at 690 V — the steep drop at 690 V means this breaker is sized for 400 V class distribution, not 690 V motor circuits.
Power loss is 6.5 W maximum, which is low enough that forced ventilation is not required in a typical IP54 steel enclosure, but check the total dissipation if multiple breakers are ganged.