Its interrupting capacity is specified per the voltage applied: 187 kA at 240 V AC, 121 kA at 415 V AC, 75.6 kA at 440 V AC, 30 kA at 500 V AC, and 17 kA at 690 V AC — these figures govern the maximum fault current the breaker can safely clear at each system voltage without upstream coordination failure.
Above that, the thermal-magnetic or electronic trip unit must be derated: 194 A at 55 °C, 188 A at 60 °C, 182 A at 65 °C, and 176 A at 70 °C. For panel builders, this means the 3VA1220-5GF42-0JC0 can be installed in a 50 °C enclosure without downsizing the main conductors, but above that temperature the load current must be reduced per the published curve.
Physical Fit and Auxiliary Components
Dimensions are 158 mm high, 140 mm wide, and 70 mm deep — a 4-pole frame that occupies roughly 5.5 inches of DIN-rail or panel-mount width.