Line protection breaker for high-fault panels
The Siemens SENTRON 3VA1225-6GF42-0AB0 is a 4-pole molded case circuit breaker (MCCB) rated for 250 A continuous current (Iu) with a TM240 thermal-magnetic overcurrent release. Its interrupting capacity reaches 220 kA at 240 V AC, 154 kA at 415 V, 36 kA at 440 V, and 17 kA at 690 V — figures that place it in the high-interrupting class for line protection applications where fault currents are severe. The 250 A rating holds flat from 40 °C through 50 °C, then derates to 243.3 A at 55 °C, 236.5 A at 60 °C, 229 A at 65 °C, and 223 A at 70 °C. That thermal curve matters when the breaker sits in a crowded enclosure — the 50 °C ceiling means no derating in most ventilated panels, but above that you need to account for the drop. Rated insulation voltage (Ui) is 800 V, and the front face carries IP40 protection — suitable for general indoor panel mounting where tools or fingers won't contact live parts through the front cover. The breaker includes 2 auxiliary switches (HP type) for status feedback to a PLC or annunciator.
Integration dimensions
The breaker measures 140 mm wide, 158 mm high, and 70 mm deep — a 4-pole footprint that fits standard SENTRON 3VA panel cutouts. The 70 mm depth keeps it within typical 200 mm deep enclosures, leaving room for rear busbar connections or cable ducting.