The Siemens SENTRON 3VA1150-4ED26-0AA0 is a 2-pole molded case circuit breaker (MCCB) rated for line protection. It carries a continuous current of 50 A at 40 °C with a TM210 thermal-magnetic overcurrent release — the fixed thermal and magnetic trip settings are factory-calibrated, so there is no dial to mis-adjust on the line. Breaking capacity is the headline number here: 121 kA at 240 V AC and 75.6 kA at 415 V AC. That puts it in the high-interrupting class for a 50 A frame — it clears a bolted fault upstream without the arc chute failing, which matters when the transformer is right around the corner from the panel. Thermal derating is published across the full operating range: full 50 A up to 50 °C, then 49 A at 55 °C, 48 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. If the panel ambient sits above 50 °C, the continuous load must be backed off accordingly — no guessing.
Panel fit and environment
Footprint is 130 mm high × 50.8 mm wide × 70 mm deep — a standard 2-pole MCCB width for DIN-rail or screw-mount panels. The front face carries IP40 protection, so it is fine inside a closed enclosure but not for washdown zones. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power loss at rated current is 9.74 W — negligible for panel thermal budgeting unless the enclosure is sealed and densely packed.