MCCB for motor protection — 100 A, ETU350M trip unit
The Siemens 3VA2110-5MN32-0DH0 is a SENTRON molded case circuit breaker (MCCB) rated for motor protection duty, carrying a continuous current Iu of 100 A across the 40 °C to 50 °C band before derating begins at 55 °C. The ETU350M electronic trip unit provides adjustable overload and short-circuit protection curves tailored to motor starting inrush, with phase failure detection built in — so a lost phase on the line side trips the breaker before single-phasing damages the winding. Breaking capacity reaches 187 kA at 240 V and 121 kA at 415/440 V, dropping to 75.6 kA at 500 V and 17 kA at 690 V. That 187 kA figure at 240 V covers high-fault utility feeds; the 121 kA at 415 V handles most industrial distribution panels. The 690 V rating of 17 kA is the limiting case — verify SCCR against the available fault current on that voltage class. The 3-pole frame includes an undervoltage release (UVR) as the auxiliary release design, plus a 2 auxiliary switch + 1 trip alarm switch HQ contact block. The UVR drops the breaker on loss of control voltage — standard for safety circuits where a downstream E-stop or undervoltage condition must open the main power path. Maximum power loss is 75 W, which matters for enclosure thermal rise calculations when grouping multiple breakers.
Integration and mounting
Dimensions are 181 mm height × 105 mm width × 86 mm depth — a standard 3-pole MCCB footprint for panel-mounting on a backplate or DIN rail adapter. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C. The 105 mm width matches the typical 3-pole SENTRON 3VA frame, so a panel laid out for a 3VA1110 or 3VA2010 will accept this unit without re-drilling the mounting holes.