Line protection MCCB with undervoltage release
The Siemens SENTRON 3VA1110-3EF32-0BH0 is a 3-pole molded case circuit breaker rated for line protection, carrying a continuous current of 100 A at 40 °C and an insulation voltage of 800 V. Breaking capacity steps from 75.6 kA at 240 V down to 10.5 kA at 690 V — that covers most industrial distribution panels where fault levels vary by tap point. The overcurrent release is a TM240 thermal-magnetic type, so it handles both overload and short-circuit without an external trip unit. It ships with an integrated undervoltage release (UVR) and a 2+1 auxiliary contact block (2 auxiliary switches + 1 trip alarm switch HQ). That means the breaker can be wired into a safety chain that drops the load on loss of control voltage, and the alarm contact gives a remote trip indication — useful for a panel where you need to know a branch tripped without walking the floor.
Current derating and thermal limits
The 100 A rating holds flat up to 50 °C ambient; above that it derates gradually — 96 A at 55 °C, 94 A at 60 °C, 92 A at 65 °C, 90 A at 70 °C. If your panel runs hot near the top of a cabinet, those derated figures are the ones to size against, not the 40 °C sticker. Operating range is -25 °C to 70 °C, storage from -40 °C to 80 °C.
Physical fit and panel integration
The breaker measures 130 mm high, 76.2 mm wide, 70 mm deep — a standard SENTRON 3VA footprint. It mounts on a DIN rail or can be screw-fixed to a backplate. The front face carries an IP40 protection class, so it's fine inside a closed panel but not for washdown zones. The 3-pole form factor means it occupies three module widths on the rail.