What this MCCB does on the line side
The Siemens 3VA1140-6EF36-0HH0 is a 3-pole SENTRON molded case circuit breaker (MCCB) set up for line protection — meaning it sits upstream protecting feeders and distribution, not a specific motor load. Rated continuous current Iu is 40 A, and it holds that rating flat from 40 °C through 50 °C before it starts to derate: 38.4 A at 55 °C, 37.6 A at 60 °C, 36.8 A at 65 °C, and 36 A at 70 °C. That thermal curve matters if this breaker lands in a warm enclosure or next to other heat sources — you lose about 10% of the 40 A rating by the time ambient hits 70 °C. Breaking capacity is the headline number here: 220 kA at 240 V, 154 kA at 415 V, 121 kA at 440 V, and 17 kA at 690 V. That 220 kA at 240 V is what you spec when the available fault current is high — large transformer secondaries, utility tie points, or industrial services where the upstream transformer can dump serious energy into a bolted fault. The 690 V rating (17 kA) is lower but still useful for 600 V class systems in North America or 690 V industrial networks in Europe.
Trip unit and auxiliary configuration
Overcurrent release is a TM240 — thermal-magnetic, fixed-trip, no electronic adjustment. That means the thermal element handles overloads, the magnetic element handles short-circuits, and you don't get the fine-tuning of an electronic trip unit. For a distribution feeder where the load is known and stable, that's fine; for variable loads or coordination-heavy designs, you'd want the electronic version. This unit ships with a shunt trip (STL) for remote tripping — voltage trigger is present. It also carries 2 auxiliary switches plus 1 trip alarm switch (HQ configuration), which gives you status feedback for the breaker position and a separate alarm contact that only changes state on a trip event. The integrated auxiliary trip uses order code 3VA9688-0BL30 if you need a replacement. No undervoltage release, no communication module, no phase failure detection, no ground fault monitoring — this is a basic distribution breaker, not a smart or selective device.
Physical fit and panel integration
Dimensions: 130 mm height, 76.2 mm width, 70 mm depth. That's a standard 3-pole MCCB footprint for the SENTRON 3VA frame size. Mounts on a DIN rail or can be screw-mounted to a backplate. The 76.2 mm width is 3 modules at 25.4 mm each — standard for panel layout. IP40 on the front means it's protected against tools and wires >1 mm, but not against water ingress; keep it inside a panel or enclosure. Rated insulation voltage Ui is 800 V, so it's rated for 690 V systems with margin. Storage temperature range is -40 °C to 80 °C; operating range is -25 °C to 70 °C. Latching endurance is 15,000 operations — that's the mechanical life for the switching mechanism, not the electrical endurance under load (which will be lower depending on the current being interrupted).