Siemens SENTRON 3VA1125-6EF32-0BC0 — 25 A MCCB with 220 kA Interrupting Rating
The Siemens SENTRON 3VA1125-6EF32-0BC0 is a 3-pole molded case circuit breaker (MCCB) rated 25 A at 40 °C, designed for line protection in distribution panels. Its interrupting capacity reaches 220 kA at 240 V AC, 154 kA at 415 V AC, and 121 kA at 440 V AC — figures that govern fault-clearing capability in high-fault-current installations. At 500 V and 690 V the rating drops to 17 kA, so verify the available fault current at the point of installation before specifying.
Breaking Capacity and Coordination
The 220 kA interrupting rating at 240 V places this MCCB in the high-fault tier for 240 V distribution — suitable for service-entrance or main-breaker duty where transformer fault currents are high. At 415 V the 154 kA rating still exceeds typical industrial panel SCCR requirements (often 65 kA or 100 kA), providing headroom for selectivity with downstream breakers. The 17 kA rating at 690 V is the limiting case; if the installation is at 690 V, confirm the available fault current is below that threshold.
Thermal Derating and Ambient Conditions
The 25 A rating holds from 40 °C through 50 °C. At 55 °C and 60 °C it derates to 24 A; at 65 °C and 70 °C it drops to 23 A. Operating ambient range is -25 °C to 70 °C, storage range -40 °C to 80 °C. For panels with elevated internal temperatures — common in enclosed switchgear or near heat sources — use the 55 °C column for continuous load sizing.
Physical Fit and Panel Integration
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth. The 76.2 mm width (3 inches) matches the standard 3-pole MCCB footprint for DIN-rail or panel-mount installation. Depth of 70 mm (2.76 in) leaves clearance for rear-connected busbars or cable lugs in a typical 200 mm deep enclosure.