What this MCCB does — and what the ratings mean for fit
The Siemens SENTRON 3VA1040-3ED36-0AH0 is a 3-pole molded case circuit breaker (MCCB) built for line protection — the standard role of guarding feeders and branch circuits against overload and short-circuit in distribution panels. Its TM210 release is a fixed thermal-magnetic trip; the thermal element handles overloads (adjustable to 40 A), and the magnetic element clears short-circuits. The 75.6 kA interrupting rating at 240 V means it can safely break a fault current up to that level without welding contacts or cascading failure upstream — critical for high-capacity panels. At 415 V it still handles 52.5 kA, and at 440 V it drops to 32 kA, so verify the available fault current at your system voltage. The 40 A rating holds flat from 40 °C to 50 °C; above that it derates gradually to 36 A at 70 °C. That thermal stability makes it a solid choice for enclosures with moderate heat rise — no need to oversize for a warm panel. Dimensions are 130 mm high, 76.2 mm wide, 70 mm deep — fits standard MCCB mounting footprints on DIN rail or backplate.
Mounting and integration notes
Mounts on DIN rail or backplate; the 76.2 mm width matches the standard 3-pole MCCB footprint — no panel rework needed if swapping from another SENTRON 3VA three-pole. IP40 on the front means it's protected against tools and wires >1 mm, but not against water; install in a dry enclosure or add a cover for washdown areas. The auxiliary contact version includes 2 auxiliary switches plus 1 trip alarm switch HQ — handy for remote status indication without adding a separate block.