63 A MCCB with shunt trip — line protection for high-fault panels
The Siemens SENTRON 3VA2063-6HN32-0HA0 is a 3-pole molded case circuit breaker rated for 63 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. Breaking capacity hits 242 kA at 240 V AC, 187 kA at 415/440 V, and 121 kA at 500 V, which places it squarely in high-fault-duty service entrance or distribution panels where available fault current is substantial. Insulation voltage is rated 800 V, so it handles 690 V line-to-line systems within margin. This variant includes a shunt trip release (STL) for remote tripping via a control signal — useful in emergency-stop circuits or automated shutdown sequences where the breaker must open on command rather than only on overcurrent. The supplied basic switch is order code 3VA20636HN320AA0, which is the core switching mechanism inside the molded case. Mounting dimensions are 181 mm high, 105 mm wide, 86 mm deep — fits standard SENTRON 3VA panel cutouts and busbar arrangements. No undervoltage release or ground-fault monitoring on this build; the auxiliary release is strictly the shunt trip.
What the ratings mean for panel fit
The 63 A rating holds flat across the 40–70 °C operating range, so no thermal derating table is needed for warm enclosures — a practical advantage over breakers that step down above 40 °C. The 242 kA interrupting rating at 240 V means the breaker can safely clear a fault up to that level without rupturing or welding contacts; in a 480 V panel the same unit still clears 187 kA, which covers most industrial service-entrance conditions. The 86 mm depth keeps the breaker within standard SENTRON mounting depth, leaving room for rear busbar connections and cable egress. Power loss is 5.4 W maximum — negligible for thermal budgeting inside the enclosure, but worth noting if the panel is densely packed with multiple breakers in a sealed box.