MCCB for line protection — 32 A, 121 kA SCCR at 240 V
The Siemens SENTRON 3VA1132-4EF36-0DC0 is a 3-pole molded case circuit breaker rated for a continuous current of 32 A at 40 °C, with a TM240 thermal-magnetic overcurrent release. Its interrupting capacity hits 121 kA at 240 V, 75.6 kA at 415 V, and 52.5 kA at 440 V — figures that cover most industrial service-entrance and feeder applications where high fault current is expected. At 690 V it still clears 11.9 kA, so it handles line-side protection in 690 V drives or transformer secondaries without cascading upstream. The TM240 release means the thermal pickup is fixed at 32 A; the magnetic trip threshold is set at 240 A (7.5× In). That suits motor feeder or distribution circuits where you want a high short-circuit trip to ride through inrush without nuisance tripping. The breaker carries an undervoltage release (UVR) as standard — if control voltage drops, the breaker opens, which is common in safety circuits or emergency-stop chains that need a loss-of-voltage trip. Rated insulation voltage is 800 V, so it can be used in 690 V systems with margin. The front face is IP40 — fine for a clean indoor panel, but not for washdown or outdoor exposure. Two auxiliary switches (HQ type) are built in for remote status feedback; the auxiliary trip module is order code 3VA9608-0BB25 if you need a shunt trip or additional signaling later.
Thermal derating curve — full 32 A up to 50 °C
The breaker carries its full 32 A rating 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 the panel ambient runs above 50 °C, size the circuit for the derated value — the TM240 release is temperature-compensated within its design range, but the continuous current limit shifts. Storage range is -40 °C to 80 °C; operating range is -25 °C to 70 °C. Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a standard 3-pole MCCB footprint that fits most DIN-rail or panel-mount enclosures without re-drilling. The 76.2 mm width is three 25.4 mm pole pitches, so it aligns with busbar systems and terminal blocks on the same grid.