63 A MCCB with 242 kA interrupting — what that means for your panel
The Siemens 3VA2063-6HL32-0AB0 is a SENTRON 3VA2 molded case circuit breaker rated for 63 A continuous current (Iu) with an ETU320 electronic trip unit. The headline number here is the interrupting capacity: 242 kA at 240 V AC, dropping to 187 kA at 415 V and 440 V, 121 kA at 500 V, and 4 kA at 690 V. That 242 kA figure means this breaker can safely clear a fault of that magnitude without welding its contacts or rupturing the case — critical for high-fault panels downstream of large transformers or in industrial mains distribution. The 3-pole construction handles three-phase loads, and the IP40 front protection keeps dust out of the enclosure face.
Thermal derating and trip unit — the real selection data
This breaker holds its full 63 A rating up to 50 °C ambient. Above that, it derates linearly: 60.6 A at 55 °C, 58.3 A at 60 °C, 55.9 A at 65 °C, and 53.6 A at 70 °C. If your panel ambient runs hot — say, a non-ventilated enclosure near a furnace line — you need to account for that drop. The ETU320 electronic trip unit gives you adjustable overload and short-circuit protection curves; it's not a fixed thermal-magnetic, so you can dial in coordination with downstream breakers. The unit ships with 2 auxiliary switches (HP type) for status feedback to a PLC or annunciator panel.
Physical fit — dimensions and panel integration
The breaker measures 105 mm wide, 181 mm tall, and 86 mm deep. That 105 mm width is a standard 3-pole MCCB footprint — it fits the same mounting hole pattern and busbar spacing as other 3VA2 frames in the 63 A range. The 86 mm depth means it clears most standard enclosure depths without needing a protruding cover. Mounts via screw terminals to a backplate or DIN rail adapter; the SENTRON series uses a common accessory set (busbar connectors, shunt trips, auxiliary contacts) across the 3VA2 family.