What it is and what it does
The Siemens SENTRON 3VA1132-4EF32-0CA0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a rated current of 32 A at 40 °C, with thermal-magnetic overcurrent release type TM240. The breaker holds a rated insulation voltage of 800 V. Breaking capacity is 121 kA at 240 V AC, 75.6 kA at 415 V, and 52.5 kA at 440 V — high enough for most secondary distribution applications where fault currents are substantial. At 690 V it still interrupts 11.9 kA. This variant includes an undervoltage release (UVR) as the auxiliary release, which trips the breaker if the control voltage drops below a set threshold — useful for motor circuits that must not auto-restart after a dip.
Sizing and thermal considerations
The 32 A rating holds steady from 40 °C up to 50 °C, then derates to 31 A at 55–60 °C and 30 A at 65–70 °C. That thermal curve means you can run it near its nameplate in a warm panel without stepping down a frame size, but above 50 °C you lose about 1 A per 10 °C. Maximum power loss is 13.1 W — modest for a 32 A MCCB, but worth checking against the enclosure thermal budget if the panel is densely packed. Physical footprint: 130 mm height, 76.2 mm width, 70 mm depth. It's a standard SENTRON 3VA frame size — fits existing DIN-rail or screw-mount patterns in most Siemens and generic switchgear.