Siemens SENTRON 3VA1140-5EF32-0AG0 — 40 A MCCB with TM240 Release
The Siemens SENTRON 3VA1140-5EF32-0AG0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, with a continuous current of 40 A at 40 °C and a TM240 thermal-magnetic overcurrent release. Its interrupting capacity reaches 187 kA at 240 VAC, 121 kA at 415 VAC, and 75.6 kA at 440 VAC — figures that govern selectivity and SCCR coordination in high-fault panels. The insulation voltage is rated at 800 V, and the breaker includes one auxiliary switch plus one trip alarm switch (HP design).
Interrupting Capacity and Selectivity Coordination
At 240 V the breaker clears 187 kA; at 415 V it clears 121 kA; at 440 V it clears 75.6 kA; at 500 V and 690 V it clears 17 kA. These are the values an electrical engineer uses to verify upstream breaker coordination and downstream SCCR compliance per IEC 60947-2. The TM240 release provides thermal-magnetic protection with a fixed thermal pickup at 40 A and a magnetic trip threshold set at 240 A (6× In).
Thermal Derating and Operating Range
The breaker carries a full 40 A from 40 °C through 50 °C ambient. At 55 °C it derates to 39 A, at 65 °C to 38 A, and at 70 °C to 37 A. Operating ambient range is -25 °C to +70 °C; storage range is -40 °C to +80 °C. Maximum power loss is 10.8 W. These derating curves matter when the breaker is mounted in a sealed enclosure or alongside heat-generating components.
Dimensions and Panel Fit
Width is 76.2 mm (3 in), height 130 mm (5.12 in), depth 70 mm (2.76 in). The 3-pole footprint matches the standard SENTRON 3VA mounting pattern; it installs on a DIN rail or via screw-mount to a backplate. The auxiliary switch configuration (1 aux + 1 trip alarm, HP) is factory-integrated — no separate add-on module required.