What this MCCB is and what it does
The Siemens SENTRON 3VA1220-6MH32-0CC0 is a 3-pole molded case circuit breaker (MCCB) rated for 200 A continuous current, designed specifically for starter protection — meaning it's built to handle the inrush and overload profile of motor starters and contactor-controlled loads in a panel. Its interrupting ratings climb to 220 kA at 240 V, 154 kA at 415 V, and 75.6 kA at 440 V — figures that tell you this breaker can clear high-fault currents on the secondary side of a distribution transformer without welding its contacts or venting arc gas into the enclosure. At 500 V the interrupting rating drops to 30 kA, and at 690 V to 4.5 kA, so it's not a candidate for 690 V high-fault panels unless the available fault current is known to be under that threshold.
Thermal derating — what 200 A means at panel ambient
The 200 A rating holds at 40 °C, 45 °C, and 50 °C without derating. At 55 °C it drops to 194 A, at 60 °C to 188 A, at 65 °C to 182 A, and at 70 °C to 176 A. If your panel ambient runs above 50 °C — common in enclosed MCC lineups with multiple breakers — size the load side for the derated figure, not the nameplate 200 A. Maximum power loss is 44.5 W, which matters for enclosure heat-rise calculations when the breaker is fully loaded.
Auxiliaries and releases fitted
This variant ships with an undervoltage release (UVR) and two HQ auxiliary switches. The UVR trips the breaker when control voltage drops below the dropout threshold — standard for safety circuits that need to drop a motor starter on loss of control power. The two auxiliary switches provide status feedback (open/closed) to a PLC or indication lamp without needing a separate contact block. No communication function, no ground-fault monitoring, and no voltage-trip module are fitted on this order code. If you need those, you're looking at a different suffix in the 3VA1 family.
Physical fit and panel integration
Dimensions are 105 mm wide, 158 mm high, 70 mm deep. That's a standard 3-pole MCCB footprint for the 200 A frame size — mounts on a DIN rail or direct to a backplate via the breaker's own mounting lugs. The 70 mm depth means it clears most shallow enclosures, but verify the door-swing clearance if the breaker is mounted near the hinge side. Rated insulation voltage is 800 V, operating temperature range -25 °C to 70 °C, storage range -40 °C to 80 °C. The storage minimum matters if this sits in an unheated warehouse over winter.