What this MCCB is and what it does
The Siemens SENTRON 3VA1220-5MH32-0HC0 is a 3-pole molded case circuit breaker (MCCB) rated for a continuous current Iu of 200 A, with a breaking capacity of 187 kA at 240 V and 121 kA at 415 V. It is configured as a starter protection device, meaning it is designed to sit ahead of a motor starter or contactor, providing short-circuit and overload protection for the motor branch circuit. The TM120M thermal-magnetic release handles the overload curve and instantaneous trip; the shunt trip (STL) allows remote tripping from a PLC or emergency-stop circuit. Two HQ auxiliary switches (3VA9688-0BL30) are integrated for status feedback to the control system.
Breaking capacity and what it means for your line
The 187 kA at 240 V is the high interrupting rating that matters for large transformer-fed panels or high-fault utility feeds — it means this MCCB can safely clear a bolted fault up to that level without rupturing. At 415 V the rating drops to 121 kA, still well above typical industrial service-entrance levels. At 440 V it is 30 kA, and at 690 V it is 17 kA. If your installation is on a 480 V wye or 400 V delta system, the 415 V figure governs; for 690 V wind-farm or mining applications the lower figure applies. The 800 V rated insulation voltage (Ui) confirms the internal clearances are sized for 690 V line-to-line operation.
Thermal derating — the real current you can carry
The 200 A rating holds flat from 40 °C through 50 °C ambient. Above that it steps down: 192 A at 55 °C, 188 A at 60 °C, 184 A at 65 °C, and 180 A at 70 °C. If the MCCB is mounted in a sealed enclosure or near heat-generating drives, use the 60 °C or 70 °C column for the actual continuous current the breaker will carry without nuisance tripping. The operating temperature range is -25 °C to +70 °C; storage range is -40 °C to +80 °C.
Panel fit and integration
Dimensions are 158 mm high, 105 mm wide, 70 mm deep. The width of 105 mm is standard for a 200 A frame MCCB — it fits a typical 3-pole MCCB cutout in a panel or enclosure. The IP40 rating on the front means it is protected against solid objects over 1 mm (tools, wires) but not against water ingress; mount it inside a cabinet or use a gland plate for washdown areas. The shunt trip coil draws power only during the trip event; verify the control voltage matches the STL rating before wiring.
What it does not include
This variant has no undervoltage release, no phase-failure detection, no ground-fault monitoring, and no communication module. It is a standalone thermal-magnetic breaker with a shunt trip and two auxiliary switches. If you need undervoltage protection or ground-fault sensing, you would select a different 3VA variant or add external relays. The latching endurance is rated at 15 000 operations — sufficient for motor-starting duty but not for frequent switching as a disconnect.