What this MCCB is and what it does
The Siemens 3VA2110-5HN32-0AJ0 is a SENTRON molded case circuit breaker (MCCB) with a 1200 A frame, rated for 100 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. It is a 3-pole, line-protection device designed for distribution and feeder circuits in industrial panels. Interrupting capacity is 187 kA at 240 V AC, 121 kA at 415/440 V, 75.6 kA at 500 V, and 3.7 kA at 690 V — so the breaker can clear high fault currents at common distribution voltages without upstream coordination issues. Rated insulation voltage is 800 V, and maximum power loss is 10 W. The breaker includes a trip indicator and carries 2 auxiliary switches plus 1 trip alarm switch (HP type) for remote status monitoring.
Dimensions and panel fit
The 3VA2110-5HN32-0AJ0 measures 86 mm deep, 105 mm wide, and 181 mm tall. The 105 mm width (4.13 in) is standard for a 3-pole MCCB.
What the ratings mean for your panel
The 100 A continuous rating is flat from 40 °C to 70 °C — no thermal derating curve to calculate for warm enclosures. The 1200 A frame means the breaker's internal mechanism and contacts are sized for that ultimate current; the installed trip unit is set for 100 A. Interrupting capacity at 240 V (187 kA) covers most industrial service-entrance and feeder applications; at 690 V (3.7 kA) the breaker still clears faults but is best applied where available fault current is lower, such as on the secondary side of a step-down transformer. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The auxiliary switch configuration (2 aux + 1 trip alarm) provides three dry contacts for PLC or SCADA inputs — enough for status, trip, and a spare without adding an external auxiliary module.