Breaking capacity — what the voltage columns tell you
The 3VA1140-4EF36-0AC0: This breaker delivers 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. The steep drop above 440 V is typical for a compact-frame MCCB; at 690 V the 11.9 kA figure still covers most industrial distribution faults, but if your secondary side runs at 480 V or 600 V class, verify the available fault current against the 52.5 kA or 11.9 kA column respectively.
Thermal derating — the 40 A rating holds to 50 °C
The continuous current rating stays at 40 A from 40 °C through 50 °C, then drops to 39 A at 55–60 °C, 38 A at 65 °C, and 37 A at 70 °C. That means in a warm panel (50 °C internal ambient) you still get full 40 A per pole; above that, apply the derating curve rather than oversizing the frame. The insulation voltage is rated 800 V, so the 690 V breaking column is within the insulation envelope.
Panel fit and auxiliary switch
Footprint is 76.2 mm wide, 130 mm tall, 70 mm deep — a standard 3-pole MCCB width that fits most DIN-rail or panel-mount enclosures without re-drilling. The breaker ships with two auxiliary switches (HQ type) factory-installed, so you get status feedback without ordering a separate accessory kit. No undervoltage release, no ground-fault monitoring, no communication module on this variant.