What this MCCB does on the line
The Siemens SENTRON 3VA1040-3ED46-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated 40 A at 40 °C, designed for line protection — meaning it sits at the feeder or subfeeder to protect cable and bus against overload and short circuit, not for direct motor starting duty. Its TM210 overcurrent release is a fixed thermal-magnetic trip: the thermal element handles overloads, the magnetic element handles short-circuits, with no adjustable trip curve — set it and forget it, which simplifies panel build but means you size the breaker to the load, not tune it. Breaking capacity runs 75.6 kA at 240 V AC, 52.5 kA at 415 V, and 32 kA at 440 V — numbers that tell you this breaker handles high available fault current on a 240/415 V distribution bus without needing a current-limiting fuse upstream. Rated insulation voltage is 800 V. IP40 front protection keeps tools and fingers out.
Thermal derating and panel fit
The 40 A rating holds flat from 40 °C to 50 °C, then derates to 39 A at 55–60 °C and 38 A at 65 °C, 37 A at 70 °C — so in a warm panel (say 55 °C ambient) you lose only 1 A, but at 70 °C you're down to 37 A continuous. Dimensions are 70 mm deep, 101.6 mm wide, 130 mm tall. Maximum power loss is 10.8 W. Operating range is -25 °C to 70 °C; storage range -40 °C to 80 °C — fine for unheated warehouses as long as the breaker is not energized below -25 °C.
Lifecycle and sourcing posture
The part is specified into new panels across the 3VA platform. Availability and current pricing are confirmed at quote time against an RFQ through independent distribution.