What this MCCB is and what it does
The Siemens SENTRON 3VA2140-6JQ32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, designed for line protection in distribution panels. Its 242 kA breaking capacity at 240 V AC means it can safely interrupt fault currents up to that level without upstream cascading — critical for high-fault installations like transformer secondaries or large motor control centers. The 800 V rated insulation voltage gives headroom for 480 V and 600 V class systems.
Breaking capacity across voltage levels
This MCCB delivers 242 kA at 240 V, 187 kA at both 415 V and 440 V, 121 kA at 500 V, and 3.7 kA at 690 V. The steep drop at 690 V is typical for a 40 A frame — the arc extinction limits at higher voltages. For 480 V systems (common in North American industrial), the 187 kA figure at 440 V is the closest published rating; expect similar or slightly lower performance at 480 V. The 3.7 kA at 690 V still covers most 690 V distribution fault levels.
Thermal performance and derating
The breaker holds its full 40 A rating from 40 °C through 70 °C ambient — no derating needed across that span. That simplifies panel design in warm enclosures or near heat sources. Power loss is 1.6 W maximum, negligible for thermal budgeting. Operating range is -25 °C to 70 °C; storage from -40 °C to 80 °C.
Physical fit and panel integration
Dimensions are 181 mm high, 105 mm wide, 86 mm deep — a standard MCCB footprint for this current class. The 105 mm width (4.13 in) is the critical dimension for multi-pole grouping on a DIN rail or panel-mount plate. Verify busbar spacing and enclosure depth against the 86 mm (3.39 in) depth, especially in shallow pull-boxes.
Ground-fault and communication features
This variant includes ground-fault monitoring via summation current formation on the L-conductor — it detects leakage by summing phase currents, not a separate neutral CT. The communication function (likely a modular communication module option) allows integration with building management or SCADA systems for remote trip indication and load monitoring.