What this MCCB carries
The Siemens SENTRON 3VA2063-5JQ32-0JA0 is a 3-pole molded case circuit breaker rated for 63 A continuous at 40 °C through 70 °C with no derating — that means it holds full current across the typical panel ambient without a temperature knock-down factor. It is designed for line protection, not feeder or motor protection, so the trip curve is fixed for cable and busbar fault isolation. The interrupting ratings climb to 187 kA at 240 V and 121 kA at 415/440 V, dropping to 75.6 kA at 500 V and 3 kA at 690 V. That 187 kA at 240 V is the number to check if this breaker sits downstream of a large transformer on a 240 V delta secondary — it can clear a bolted fault without cascading upstream. The unit includes a shunt trip release (STL) for remote opening — a separate control voltage triggers the trip coil to drop the breaker under emergency stop or supervisory control. The basic switch variant is 3VA20635JQ320AA0. Maximum power loss is 5.4 W, manageable for enclosure heat budgets.
Panel fit and footprint
Dimensions are 105 mm wide, 181 mm high, and 86 mm deep. That 105 mm width is the key panel constraint — it occupies three standard 35 mm DIN-rail module positions (each 17.5 mm plus air gap). Depth of 86 mm means it clears a 120 mm deep enclosure with room for rear busbars. The 3-pole form factor matches standard SENTRON mounting bases; no adapter plate needed for most Siemens switchboards.