Four-pole construction with the neutral unprotected; the TM220 thermal-magnetic trip unit provides line protection with an adjustable overload range of 350 A to 500 A and a fixed short-circuit pickup at 10 times the rated current (Ii = 10 x In). The ATFM designation indicates the trip unit includes a thermal memory function for motor-starting duty.
At 70 kA Icu @ 415 V, this breaker sits in the high-interrupting tier of the 3VA1 family — suitable for main or tie positions where fault current exceeds 50 kA. The class H rating (Ics typically 100% Icu for this series) means it can be reclosed after a fault at full rating without derating, which matters for critical process feeders where a blown fuse or welded contacts mean extended downtime.
Panel integration
The 4-pole footprint occupies standard 630 A frame space; verify panel cutout and busbar spacing against the 3VA1 mounting template before laying out the gland plate.