The Siemens SENTRON 3VM1125-5EE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated 25 A continuous at 40 °C ambient, with a TM220 thermal-magnetic overcurrent release. Its interrupting capacity hits 187 kA at 240 V AC — that's the number to check against your available fault current on the line side; at 415 V it still holds 121 kA, and at 500 V it drops to 17 kA, so verify the voltage class at the point of installation. Rated insulation voltage is 690 V, and the front panel carries IP40 protection, meaning it's dust-protected but not sealed against hose-down.
Dimensions & Panel Fit
Depth is 70 mm, width 101.6 mm, height 130 mm. Fits standard DIN-rail or panel-mount cutouts for a 4-pole MCCB in the SENTRON 3VM frame. Check the mounting footprint against your existing busbar or terminal block layout — the 101.6 mm width is a common 4-inch pitch, so it aligns with standard distribution panel spacing.
Thermal Derating & Operating Range
The 25 A rating holds steady from 40 °C up to 50 °C. At 55 °C it derates to 24 A, and at 70 °C it's 23 A. Ambient operating range is -25 °C to 70 °C; storage range goes -40 °C to 80 °C. Maximum power loss is 9 W — negligible for panel thermal budgeting but worth noting if you're packing multiple breakers in a sealed enclosure.