The Siemens 3VA2163-7MS32-0AC0 is a SENTRON molded case circuit breaker (MCCB) designed specifically for starter protection — meaning it's built to handle the high inrush and locked-rotor currents of motor circuits, not just general distribution. It carries a continuous rating of 63 A across the full 40 °C to 70 °C ambient range, so no derating curve to chase when it's mounted in a warm enclosure next to a contactor.
Interrupting capacity by voltage
This breaker clears faults up to 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 3.7 kA at 690 V. That 330 kA at 240 V means it handles very high available fault current on the secondary side of a step-down transformer without needing a current-limiting fuse upstream — a real space saver on the rail.
Current range and adjustment
The trip unit adjusts from a minimum of 189 A to a maximum of 945 A, which is the short-circuit and overload pickup range, not the continuous rating. The continuous current is fixed at 63 A by the frame and thermal elements; the 189–945 A band sets the magnetic trip level for motor-starting inrush.
Physical fit and wiring
It measures 105 mm wide, 181 mm tall, and 86 mm deep — a standard 3-pole MCCB footprint that drops into the same DIN-rail or panel-mount space as other SENTRON 3VA2 breakers. The depth of 86 mm leaves room for rear busbar connections in a shallow backpanel. The supplied basic switch is order code 3VA2163-7MS32-0AA0, and the breaker comes with two HQ auxiliary switches built in — so you get status feedback without adding a separate side-mount block.
Environmental limits
Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The 4 W maximum power loss is low enough that you don't need to derate adjacent devices in a packed panel.