What it is and what it does
The Siemens 3VA1220-6EF42-0AE0 is a SENTRON molded case circuit breaker (MCCB) — a 4-pole line-protection device rated for a continuous current of 200 A. Its TM240 thermal-magnetic release provides overload and short-circuit protection in a single unit, sized for main feeders or large sub-distribution in industrial switchboards.
Breaking capacity and thermal derating — what the numbers mean for your panel
Breaking capacity is the fault current the breaker can safely interrupt without welding or rupturing. At 240 V this MCCB clears 220 kA; at 415 V it clears 154 kA; at 440 V it clears 36 kA; at 690 V it clears 17 kA. That 220 kA figure at 240 V puts it in the high-interrupting class — suitable for transformer secondaries or bus-tie positions where available fault current is high. The 200 A rating holds steady from 40 °C up to 50 °C, then derates linearly to 176 A at 70 °C. If the panel ambient runs above 50 °C, size the load accordingly.
Physical fit and auxiliary contacts
The breaker measures 140 mm wide, 158 mm high, and 70 mm deep. It ships with four auxiliary switches (HQ type) pre-installed — no separate add-on module needed for status feedback to a PLC or SCADA system. The front face carries an IP40 rating, meaning protection against tools and small wires, but not against water ingress; mount it inside a closed panel.