What it is and what it does
The Siemens 3VA2025-7JQ32-0AA0 is a SENTRON molded case circuit breaker (MCCB) rated for 25 A continuous current across a 3-pole configuration, designed for line protection in distribution panels. It carries a 242 kA breaking capacity at 415 V — that's the fault current it can safely interrupt without welding contacts or cascading failure upstream — and 330 kA at 240 V, dropping to 187 kA at 500 V and 3 kA at 690 V. The 0.5 W maximum power loss means negligible heat in a crowded DIN-rail enclosure.
What the ratings mean for fit
The 25 A continuous rating holds flat from 40 °C through 70 °C ambient — no derating curve to chase in a warm panel. Ground-fault monitoring uses summation current formation on the L-conductor, so it catches leakage without a separate GFCI module. Communication function is onboard, which saves a slot versus breakers that need an add-on comm module. The 86 mm depth and 105 mm width fit a standard MCCB footprint; panel fill factor is predictable for a 3-pole unit at this ampacity.
Physical integration
Dimensions are 86 mm deep by 105 mm wide by 181 mm tall. The 3-pole body mounts on a DIN rail or panel-mount base; the 0.5 W dissipation keeps internal cabinet temperature rise minimal even in a sealed enclosure. Rated insulation voltage is 800 V, so it's comfortable in 480 V and 600 V class systems with headroom.