What it is and what it does
The Siemens 3VA2063-5JQ32-0BL0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection in three-phase distribution. It carries a full-scale current of 63 A, flat across the ambient range from 40 °C to 70 °C — no derating needed up to that ceiling, which simplifies panel thermal budgeting. The interrupting capacity hits 187 kA at 240 V, 121 kA at 415/440 V, and still holds 75.6 kA at 500 V, so it handles high-fault scenarios downstream of a large transformer or on a stiff utility feed.
Key ratings and what they mean for fit
The 63 A rating is the breaker's continuous current at any ambient from 40 °C to 70 °C — no thermal derating curve to chase, which is unusual for a compact MCCB. That means a panel designed for 63 A at 40 °C still holds the same rating if the enclosure runs hotter. The interrupting capacity of 187 kA at 240 V and 121 kA at 415 V gives substantial SCCR headroom for most industrial distribution panels; the drop to 3 kA at 690 V tells you this is a 480 V class breaker, not a 690 V one. The 3-pole design with an undervoltage release (UVR) and communication function means it can be integrated into a monitored distribution scheme — the UVR drops the breaker on loss of control voltage, and the communication link allows remote tripping or status readback. The auxiliary switch configuration includes two auxiliary switches, one trip alarm switch, and one electrical alarm switch (HQ type), giving four discrete signals for PLC or SCADA inputs.
Panel integration and physical fit
The breaker measures 105 mm wide, 181 mm tall, and 86 mm deep — a compact footprint for a 63 A MCCB with this interrupting capacity. It mounts on a DIN rail or can be screw-fixed to a backplate. The 86 mm depth leaves room for wiring behind the breaker in a standard 200 mm deep enclosure. The undervoltage release and communication module add some depth on the side, but the overall envelope stays within the SENTRON 3VA family's typical panel cutout.