The Siemens SENTRON 3VA1140-3EF46-0AA0 is a 4-pole molded case circuit breaker (MCCB) from the 3VA series, designed for line protection. Rated at 40 A continuously at 40 °C, it uses a TM240 thermal-magnetic overcurrent release — that's a fixed thermal trip with magnetic short-circuit pickup, no electronic adjustment. Breaking capacity is what you'd expect from a compact MCCB: 75.6 kA at 240 V, 52.5 kA at 415 V, and still 11.9 kA at 690 V, so it handles fault currents on most low-voltage distribution systems without a problem.
What the ratings mean for your panel
The 40 A rating holds from 40 °C up to 50 °C without derating — at 55 °C it's 39 A, at 70 °C it's 37 A. That thermal curve matters if this breaker sits in a crowded enclosure or near a heat source; you don't lose much capacity until things get really hot. The 800 V rated insulation voltage tells you the internal clearance and creepage are good for 690 V systems, which is common in industrial distribution. IP40 on the front means tools or fingers won't reach live parts, but the rest of the breaker isn't sealed — mount it inside a panel, not in a washdown area.
Physical fit and wiring
Dimensions: 130 mm tall, 101.6 mm wide, 70 mm deep (-). That 70 mm depth is the can depth behind the panel face — it's compact enough for shallow enclosures but check your gland plate clearance. Four poles in a single molded case; line and load lugs are standard. No undervoltage release or shunt trip built in, so if you need remote tripping you'll add an accessory. Power loss at rated load is 10.8 W maximum — negligible for thermal budgeting in most panels.