What the 55 kA Icu Rating Means for Your Panel
For a motor protection circuit, this means it sits upstream of a motor starter and handles the worst-case bolted fault the supply can deliver without cascading to the next device. The ETU860M trip unit gives you LSIG protection — long-time (overload), short-time, instantaneous, and ground-fault — with an adjustable overload range of Ir=63 A to 160 A, so it covers motor FLA from about 50 A up to 160 A depending on the tap setting.
Deployment Context — Motor Control Center or Distribution Panel
This 3VA2 breaker mounts in a fixed or withdrawable chassis within an IEC motor control center or low-voltage switchgear assembly. The included nut keeper kit and the undervoltage release (UVR) are factory-fitted, so the panel builder only needs to torque the line and load connections. Ground-fault protection is adjustable Ig=0.2 to 1 x In with a time delay tg=0.05-0.8 s, which coordinates with downstream GFCI devices on feeder circuits.