What this MCCB delivers on the line
The Siemens 3VA1132-4EF32-0KA0 is a 3-pole SENTRON molded case circuit breaker rated for 32 A continuous current (Iu) at 40 °C, with the TM240 thermal-magnetic overcurrent release. Breaking capacity runs 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 690 V — so it clears high-fault downstream of a transformer or upstream of a distribution panel without cascading failure. Rated insulation voltage is 800 V, and the front face carries IP40 protection — fine for a clean indoor panel, but not for washdown areas.
Current derating — what the thermal curve means for your panel
The breaker holds 32 A from 40 °C through 50 °C without derating. At 55 °C it drops to 30.72 A, at 60 °C to 30.08 A, at 65 °C to 29.44 A, and at 70 °C to 28.8 A. If your enclosure runs hot — say a packed panel near a molding machine — size the load or vent the cabinet to stay above the 50 °C threshold and avoid nuisance tripping.
Integrated shunt trip and auxiliary options
This version ships with a shunt trip (STL) auxiliary release built in — no separate undervoltage release, no auxiliary contact block, no communication module. The integrated auxiliary trip uses order code 3VA9688-0BL33 if you need a spare or replacement. Mechanical endurance is rated at 15,000 operations, which covers routine switching in a motor control center but not high-cycle applications.