Three-pole, line protection via an ETU350 electronic trip unit with LSI curves: long-time pickup Ir adjustable 160–400 A, short-time pickup Isd 1.5–10 x Ir, and instantaneous Ii fixed at 10 x In.
The 55 kA Icu at 415 V places this breaker in the M breaking capacity class — sized for industrial distribution panels where fault currents can exceed 25 kA but stay below the 70 kA+ range of the H class. The ETU350 LSI trip gives selective coordination downstream: the adjustable short-time delay (Isd) lets you ride through motor inrush without nuisance tripping, while the instantaneous (Ii) at 10 x In provides fast clearing for bolted faults. The undervoltage release (208–230 V AC) automatically opens the breaker on loss of control voltage — common in emergency-stop chains or undervoltage protection schemes on conveyor and pump panels.
Integration notes
Mounts in a standard IEC frame 400 footprint — compatible with Siemens 3VA2 busbar systems and panel-mounting kits. The auxiliary switch and trip alarm share the same wiring channel; verify the changeover contact assignment against the panel schematic before energizing. The undervoltage release coil draws continuous current when the breaker is closed and the control voltage is present — factor that into the 24 VDC or 230 VAC control transformer sizing.