What it is and what it does
The Siemens SENTRON 3VA1025-4ED32-0HH0 is a 3-pole molded case circuit breaker (MCCB) rated for 25 A continuous current at 40 °C, designed for line protection in industrial distribution panels. Its interrupting capacity reaches 121 kA at 240 VAC, 75.6 kA at 415 VAC, 52.5 kA at 440 VAC, and 11.9 kA at both 500 VAC and 690 VAC — figures that govern fault-clearing capability at the point of common coupling.
Ratings and what they mean for fit
The 25 A rating holds across 40 °C to 50 °C ambient; above that it derates to 24 A at 55–60 °C and 23 A at 65–70 °C. That thermal curve is the one to check when the breaker sits in a crowded enclosure or near heat sources. Rated insulation voltage is 800 V, so the breaker is suitable for 690 V systems with margin. The 121 kA SCCR at 240 V means it can be applied on high-fault-capacity services without cascading upstream — a key selectivity consideration for panel builders.
Integration and auxiliary configuration
The breaker ships with 2 auxiliary switches plus a trip alarm switch (HQ) factory-installed, and includes a shunt trip (STL) release — so it arrives ready for remote tripping and status feedback without additional ordering. Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — standard 3-pole MCCB footprint for DIN-rail or screw-mount panel integration. No undervoltage release or ground-fault monitoring on this variant.