What the interrupting ratings mean for your panel
The Siemens SENTRON 3VA1225-5FF42-0AB0 is a 4-pole molded case circuit breaker (MCCB) rated for 250 A continuous current with a TM240 thermal-magnetic release, configured for line protection. Its interrupting capacity hits 187 kA at 240 V, 121 kA at 415 V, and 36 kA at 440 V — figures that govern selective coordination in high-fault panels. At 690 V it still holds 17 kA, which means this breaker clears a fault before the upstream device trips, keeping the rest of the bus live. The 250 A rating holds flat from 40 °C to 50 °C; above that it 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. If your panel ambient runs above 50 °C, the 250 A nameplate is not the usable number — the 70 °C figure of 223 A is what governs the load you can actually protect.
Physical fit and panel integration
Dimensions are 70 mm deep, 140 mm wide, 158 mm tall. The 140 mm width is a standard 4-pole MCCB footprint for DIN-rail or bolted busbar mounting in distribution panels. IP40 on the front means it is protected against tools and wires >1 mm — fine for a clean indoor panel, not for washdown zones. The N-conductor protection is set to 50 %, meaning the neutral pole is rated at half the phase current, which is typical for 4-wire systems where the neutral carries only unbalanced load.
Auxiliary contacts and release configuration
Comes with 2 auxiliary switches (HP type) built in — no separate add-on module needed for status feedback to a PLC or remote indication. No undervoltage release, no shunt trip, no communication module, no ground-fault monitoring. The overcurrent release is the TM240 thermal-magnetic type, which provides fixed thermal and magnetic trip settings for straightforward line protection without adjustment.