What it is and what the ratings mean
The Siemens 3VA2040-6JQ46-0AA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It's a 4-pole unit rated at 40 A continuous current, and it holds that rating flat from 40 °C all the way up to 70 °C ambient — no derating curve to chase in a hot enclosure. The 242 kA breaking capacity at 240 V is the headline number that tells you this breaker can sit at the main service entrance or a high-fault subfeed where available fault current is substantial. At 415 V and 440 V it still delivers 187 kA, and at 500 V it's 121 kA; the 3 kA at 690 V is the tail end of the curve for odd-voltage industrial loads.
Panel integration and footprint
The breaker measures 86 mm deep, 140 mm wide, and 181 mm high. The 86 mm depth clears most standard enclosure back-pan depths. The 140 mm width for a 4-pole MCCB is a standard SENTRON frame size, so busbar kits and mounting feet fit without modification.
Selectivity and coordination
With a minimum trip setting of 60 A and a full-scale value of 40 A, this breaker is set up for a 40 A feeder. The 800 V rated insulation voltage gives headroom for 480 V class systems. The ground-fault monitoring uses summation current formation on L + N conductor.
Communication and auxiliary functions
This MCCB includes a communication function, so it can integrate with a monitoring system for remote trip indication or load data. It does not have an undervoltage release or a voltage trigger, and there is no trip indicator on the front. The 2.2 W maximum power loss is low enough that multiple breakers in a panel don't create a thermal problem — useful when you're stacking feeders in a compact enclosure.