What this breaker carries
The Siemens 3VA1220-6GF42-0AH0 is an IEC frame 250 molded case circuit breaker with a 70 kA interrupting capacity at 415 V — class H on the 3VA1 platform. That 70 kA rating means it can safely clear a fault up to that level without welding contacts or cascading the arc upstream, which is the deciding number for panel SCCR compliance under IEC 60947-2. Four poles, line protection via a TM240 thermal-magnetic trip unit, rated In=200 A, with overload adjustable Ir=140...200 A and short-circuit pickup Ii=5...10 × In. The N conductor is protected at 100% — full-rated neutral, not a reduced section. Two auxiliary changeover switches and one trip alarm switch come fitted, so the panel builder gets status feedback and a separate alarm contact without adding external blocks.
What the ratings mean for fit
The 70 kA Icu at 415 V is the headline: it determines whether this breaker can go into a high-fault panel without a current-limiting upstream device. If your available fault current at the board is under 70 kA, this breaker clears it alone. The TM240 trip unit gives a thermal curve shaped for cable and busbar protection, not motor overload — so this is a feeder or main breaker, not a motor circuit protector. Overload adjustable from 140 to 200 A in steps, short-circuit fixed at 5 to 10 times the rated current (1000 to 2000 A at the 200 A setting). That Ii range is typical for line protection; if you need a lower magnetic pickup for a long cable run, the TM240 may not be the right trip. The 100% N conductor protection means the neutral pole is rated the same as the phase poles — important for systems with high neutral harmonics (e.g., non-linear loads, VFDs with 3rd harmonic content). The auxiliary and alarm switches are wired internally, so the panel wiring just lands on the terminal blocks — no separate mounting or adjustment.
Panel integration notes
IEC frame 250 — mounts on a standard DIN rail or can be screw-fixed to a backplate. Four-pole, so it occupies the full width of the frame; check gland-plate fill factor if the panel is tight. The TM240 trip unit is field-interchangeable within the 3VA1 frame, but the breaker ships with it fitted. Auxiliary and alarm switches are factory-installed and not field-addable on this order code — if you need more than two aux contacts, order a variant with the expanded switch pack. No external power required for the trip unit; it's self-powered from the line side.