Siemens SENTRON 3VA1020-4ED46-0AA0 — 20 A MCCB, 4-Pole, High Interrupting Capacity
Its TM210 thermal-magnetic trip unit provides fixed thermal and magnetic protection, adjustable to a maximum instantaneous trip setting of 320 A (li max.), covering overload and short-circuit faults without the complexity of electronic trip adjustments. Breaking capacity reaches 121 kA at 240 VAC, 75.6 kA at 415 VAC, 52.5 kA at 440 VAC, and holds 11.9 kA at both 500 V and 690 VAC — suitable for high-fault utility feeds and transformer secondaries where available fault current exceeds standard 25–50 kA MCCB ratings.
The breaker carries its full 20 A rating from 45 °C through 55 °C ambient, then derates to 19 A at 60–70 °C — a shallow derating curve that keeps the part usable in warm enclosures without oversizing the frame. Dimensions are 70 mm deep, 101.6 mm wide, and 130 mm high — the 4-inch (101.6 mm) width matches the standard 4-pole MCCB footprint for DIN-rail or screw-mount panel integration, with IP40 protection on the front face (finger-safe behind the panel door). Maximum power dissipation is 12 W at rated load, a figure to include in enclosure thermal calculations when grouping multiple breakers in a sealed panel.