What this MCCB is and what the ratings mean for your panel
The Siemens 3VA1140-6EF32-0BH0 is a SENTRON molded case circuit breaker (MCCB) built for line protection in distribution panels. It carries a continuous 40 A rating at 40 °C — meaning it's sized for a 40 A feeder or branch circuit and will hold that load continuously in a typical 40 °C panel ambient. The 220 kA interrupting capacity at 240 V is the headline figure: this breaker can safely clear a fault up to 220,000 A without rupturing, which puts it in the high-fault-duty class for industrial mains or sub-distribution where available fault current is high. At 415 V it still interrupts 154 kA, and at 690 V it's rated for 17 kA — so the interrupting rating drops as voltage rises, which is normal for an MCCB, and you size the breaker to the available fault current at the actual system voltage. This is a 3-pole breaker with an undervoltage release (UVR) built in — the UVR will trip the breaker if the control voltage drops below a set threshold, which is common on safety circuits or emergency-stop chains where you want the breaker to drop out on loss of control power. It also includes 2 auxiliary switches and 1 trip alarm switch (HQ), so you get position feedback and a separate alarm contact that closes only on a fault trip, not a manual open. The rated insulation voltage is 800 V, which covers 480/600 V class systems with margin.
Thermal derating and operating range
The 40 A rating holds from 40 °C up through 50 °C — no derating needed in that band. At 55 °C it drops to 39 A, at 65 °C to 38 A, and at the maximum operating temperature of 70 °C it's rated for 37 A. If your panel runs hot, you need to factor that derating into the load calculation. The storage range is -40 °C to 80 °C, so it handles cold warehouses and hot shipping containers. Power loss at full load is 13.3 W maximum — that's the heat it dumps into the enclosure, which matters for thermal management in a sealed panel.
Physical fit and panel integration
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard MCCB footprint that mounts in a distribution panel or enclosure on a mounting plate. The 3-pole width of 76.2 mm (3 inches) is common for this current class, so it will drop into most panel layouts designed for SENTRON or similar MCCBs without re-drilling. The depth of 70 mm (2.76 in) leaves room behind the door for wiring and the UVR coil connections.