What this MCCB carries and where it fits
The Siemens SENTRON 3VA1112-3EF46-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for line protection. Its TM240 thermal-magnetic release is adjustable for I²t trip, letting you fine-tune the overload curve to the load without swapping the breaker. At 40 °C it carries a full 125 A continuous; that rating holds flat through 50 °C, then derates to 114 A at 70 °C — useful when the breaker sits in a warm enclosure next to other heat sources. The interrupting ratings climb with system voltage: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 11.9 kA at both 500 V and 690 V. That gives you selectivity headroom on most low-voltage distribution panels without stepping up to a larger frame.
Panel fit and thermal budget
The 3VA1112-3EF46-0AA0 occupies 101.6 mm width, 130 mm height, and 70 mm depth — a compact 4-pole footprint for a 125 A frame. Front protection is IP40, so the breaker is suited for enclosed panel mounting where tools and fingers stay out. Maximum power loss is 28.1 W; account for that in the enclosure thermal calculation, especially if the panel is densely packed. Operating range spans -25 °C to 70 °C, with storage from -40 °C to 80 °C. No undervoltage release, no communication module, and no ground-fault monitoring on this variant — it is a straight thermal-magnetic line-protection device.