Short-circuit breaking capacity is given at four system voltages: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 10.5 kA at 690 V. That covers the common industrial distribution voltages across North America (240/480 V) and Europe (400/415 V). At 415 V, the 52.5 kA rating gives solid headroom for most panelboards — you can usually achieve selective coordination downstream without oversizing upstream breakers.
Thermal derating — the real-world current limit
Above that it derates linearly: 38.4 A at 55 °C, 37.6 A at 60 °C, 36.8 A at 65 °C, and 36 A at 70 °C.
Physical fit and auxiliary contacts
Dimensions are 130 mm high, 76.2 mm wide, and 70 mm deep — a compact footprint for a 40 A MCCB that fits most DIN-rail or panel-mount arrangements.