MCCB with ETU850 — 63 A, 187 kA at 240 V
The Siemens SENTRON 3VA2063-5KP32-0KC0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a rated continuous current Iu of 63 A and an interrupting capacity of 187 kA at 240 V, 121 kA at 415 V, and 79 kA at 500 V — numbers that define its fault-clearing capability across common distribution voltages. Equipped with the ETU850 electronic trip unit, it provides adjustable protection curves and includes a communication function for integration into higher-level monitoring systems — a feature that moves this MCCB beyond basic thermal-magnetic breakers into managed power distribution. The 187 kA rating at 240 V means this breaker can safely interrupt very high fault currents at the service entrance or main distribution panel without cascading failure upstream — a critical spec for SCCR compliance in industrial switchgear.
Thermal derating and panel fit
The 63 A rating holds at ambient temperatures up to 50 °C; above that, the continuous current derates linearly to 53.55 A at 70 °C — a curve the panel designer must account for when loading the breaker near its nameplate in a warm enclosure. Dimensions of 105 mm wide by 181 mm high by 86 mm deep place it in the standard 3-pole MCCB footprint for DIN-rail or screw-mount panel integration; the 86 mm depth leaves clearance for rear-connected busbars in a typical switchboard. Maximum power loss of 5.4 W is low enough that ventilation requirements are minimal in a well-sized enclosure, but the 70 °C maximum operating ambient still governs the thermal budget — verify the internal panel temperature under full-load conditions.
Auxiliary functions and release options
The breaker includes a shunt trip (STL) for remote opening and two HQ auxiliary switches for status feedback — enough to signal the breaker state to a PLC or SCADA system without an external contact block. It does not carry an undervoltage release, ground fault monitoring, or phase failure detection; those functions must be added externally if the application requires them. The integrated auxiliary trip is order code 3VA9688-0BL33, and the supplied basic switch is 3VA2063-5KP32-0AA0 — these are the subcomponents that would be replaced if servicing the internal mechanism.
Environmental and endurance ratings
Operating temperature range spans -25 °C to 70 °C, with storage from -40 °C to 80 °C — the storage limits govern handling and warehousing, not running conditions. Mechanical endurance is rated at 20,000 cycles. Rated insulation voltage Ui is 800 V, confirming the breaker is suitable for 690 V systems with adequate margin.