What the ratings mean for fit
The Siemens SENTRON 3VA1132-5EF42-0AA0 is a 4-pole molded case circuit breaker (MCCB) carrying 32 A at 40 °C ambient — that's the continuous current it handles without tripping on a warm panel day. The TM240 thermal-magnetic release means the thermal element is sized for a 32 A frame but the magnetic short-circuit pickup is fixed at 240 A (7.5x In), so it's a line-protection breaker, not a motor-protection curve. The headline number is the interrupting capacity: 187 kA at 240 V AC, dropping to 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 500 / 690 V. That 187 kA figure at 240 V tells you this breaker is built for high-fault panels — think transformer secondaries or busway feeds where available fault current is well above the typical 25–65 kA range. The IP40 on the front means it's protected against tools and solid objects over 1 mm, but not sealed against moisture; keep it inside a deadfront enclosure on a washdown line.
Thermal derating and real-world current
The 32 A rating holds up to 50 °C ambient — no derating needed in a typical 40 °C panel. At 55 °C it drops to 31 A, at 65 °C to 30 A, and it's still carrying 30 A at 70 °C. That's a shallow derating curve, meaning the breaker runs cool enough to keep its full rating through most industrial enclosure temperatures. If your panel is in a hot attic or near a furnace, you lose 1–2 A, not 5–10.
Panel fit and integration
The 3VA1132-5EF42-0AA0 measures 70 mm deep, 101.6 mm wide, 130 mm high — a standard 4-pole MCCB footprint for DIN-rail or screw-mount panel integration. The 4-pole design (three phases plus neutral) suits three-phase line protection where the neutral needs to be switched and protected. No undervoltage release, no communication function, no ground-fault monitoring on this variant — it's a straight line-protection breaker with the TM240 release.