Line protection MCCB with shunt trip and auxiliary switches
The Siemens SENTRON 3VA1112-5EF32-0HC0 is a 3-pole molded case circuit breaker rated 125 A at 40 °C, designed for line protection in distribution panels. It carries a 187 kA interrupting capacity at 240 V — enough headroom for high-fault service-entrance or subdistribution applications where the available fault current is substantial. The breaker includes a factory-fitted shunt trip (STL) for remote tripping and two HQ auxiliary switches for status feedback to a PLC or annunciator panel.
Interrupting ratings across voltage bands
This MCCB delivers 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V. The steep drop above 440 V is typical of a high-breaking-capacity frame — at 690 V the 17 kA still covers most industrial motor branch circuits, but for a 690 V main you would want to verify the downstream coordination study.
Current derating with ambient temperature
The breaker holds 125 A continuously from 40 °C up to 50 °C, then derates to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. If the panel ambient runs above 50 °C — common in a non-ventilated enclosure near a furnace or kiln — the 114 A floor at 70 °C still leaves margin for a 100 A continuous load, but a 125 A load would need the next frame up or forced ventilation.
Panel fit and integration
Dimensions are 130 mm height, 76.2 mm width, and 70 mm depth. The 3-pole width (about 3 in) fits standard MCCB mounting feet on a DIN rail or panel-mount base. The shunt trip coil and auxiliary switches are pre-wired to terminal blocks; no additional wiring of internal accessories is needed.