What this MCCB is and what it does
The Siemens SENTRON 3VA2125-6KQ32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 25 A continuous current, designed for line protection in distribution panels and industrial switchgear. It carries a 242 kA breaking capacity at 240 V, dropping to 187 kA at 415/440 V, 121 kA at 500 V, and 3.7 kA at 690 V — so the interrupting rating stays high across common low-voltage levels, which simplifies coordination downstream. The part includes a communication function and a ground-fault monitoring version using summation current formation on the L-conductor, meaning it can report status and detect leakage without a separate relay.
Panel fit and environment
Dimensions are 105 mm wide, 181 mm tall, 86 mm deep — a standard MCCB footprint for DIN-rail or panel-mount installation. It operates from -25 °C to 70 °C and stores from -40 °C to 80 °C, so it handles unheated enclosures and warm cabinet interiors without derating. Maximum power loss is 0.6 W, negligible for thermal budgeting inside a crowded panel.