What this MCCB delivers on the line
The Siemens SENTRON 3VA2040-8JQ36-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, with an adjustable thermal-magnetic trip unit covering 60 A to 480 A — meaning you set the instantaneous pickup to match the inrush of your motor or transformer load, not a fixed value. Short-circuit breaking capacity reaches 440 kA at 240 V, 330 kA at 415/440 V, 220 kA at 500 V, and 52.5 kA at 690 V — figures that give selectivity headroom in high-fault panel feeds without cascading upstream breakers. A built-in communication function and summation-current ground-fault monitoring make this breaker panel-network-ready for remote trip indication and leakage detection, saving a separate ground-fault relay and its wiring.
Sizing and trip coordination
The adjustable trip range from 60 A to 480 A lets this single frame cover multiple load sizes — set low for a 60 A feeder or cranked up for a 480 A motor circuit — reducing SKUs on the shelf. Rated insulation voltage is 800 V, so the breaker is suitable for 480/277 V and 600 V panels with margin; the 40 A continuous rating holds flat from 40 °C through 70 °C ambient (–), no derating needed in a warm enclosure.
Lifecycle and sourcing reality
The 86 mm depth, 105 mm width, and 181 mm height (–) match the SENTRON 3VA2 frame footprint; if you are swapping from an older 5SQ2370-2YA05 series breaker, verify the mounting hole pattern and bus-bar spacing — the 3VA2 uses a different accessory interface.
Panel integration notes
Mounts on a standard DIN rail or directly to a backplate via the screw terminals; the 105 mm width occupies three 18 mm pole spaces, typical for a 3-pole MCCB in a distribution panel. Operating temperature range of -25 °C to 70 °C (–) and storage from -40 °C to 80 °C (–) cover unheated warehouses and outdoor enclosures; maximum power loss is 1.2 W, negligible for thermal budgeting.