SENTRON 3VA1112-5FE46-0AA0 — 125 A MCCB with TM220 Overcurrent Release
The Siemens SENTRON 3VA1112-5FE46-0AA0 is a 4-pole molded case circuit breaker rated for 125 A continuous current, with a TM220 thermal-magnetic overcurrent release. It is a line-protection version in the 3VA platform, designed for main feeder or large branch-circuit duty in distribution panels. The interrupting capacity is 187 kA at 240 V AC, 121 kA at 415 V, 76 kA at 440 V, and 17 kA at both 500 V and 690 V. At 690 V the 17 kA rating is the same as at 500 V — this is typical for a breaker whose arc extinction is optimized for the lower-voltage high-current regime. For DC applications the maximum rated operational voltage is 600 V. Thermal derating is flat from 40 °C to 50 °C at 125 A, then drops to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. In a warm panel (55 °C internal ambient) you lose only 3 A — the TM220 holds its rating well through the typical enclosure temperature rise.
Lifecycle & Sourcing — Current Production, Quoted to Order
The 4-pole format and TM220 release make it a standard line-protection breaker. For BOM-freeze or critical-spare planning, this is a fast mover in the SENTRON family — keep one on the shelf if the panel runs at 125 A or below.
Integration — Panel Fit and Mounting
The breaker measures 101.6 mm wide by 130 mm tall by 70 mm deep. It mounts on a DIN rail or can be screw-fixed to a backplate. The IP40 front protection means it is suited for enclosed distribution boards where the door provides the overall IP rating — not for open-panel washdown areas. Maximum power loss is 28.1 W. In a sealed enclosure with multiple breakers, account for this heat load in the thermal budget. The latching endurance is rated at 20 000 operations — sufficient for infrequent switching in a feeder role, not for daily motor-start duty.
Key Ratings at a Glance
Rated continuous current Iu: 125 A. Rated insulation voltage Ui: 800 V. Number of poles: 4. Overcurrent release design: TM220 (thermal-magnetic, fixed thermal and magnetic settings). N-conductor protection: 50 % (reduced neutral rating typical for 4-pole breakers in three-phase systems). Storage temperature range: -40 °C to 80 °C. Operating temperature range: -40 °C to 70 °C.