What the 400 A rating means for your feeder
The ABB XT5HU340AFFN000XXX is a 400 A molded case circuit breaker in the XT5H frame, rated for 600 VAC systems. That 400 A figure is the continuous current rating — it carries that load indefinitely without tripping, making it a main or large feeder breaker for a 400 A panelboard or switchboard. The 3-pole configuration matches three-phase wye or delta services.
Trip unit: EKIP DIP LSI IN400
The EKIP DIP LSI trip unit provides adjustable Long-time (L), Short-time (S), and Instantaneous (I) protection curves. The IN400 designation means the trip unit is rated for a 400 A sensor — matched to the breaker frame. The DIP switches on the front face let you adjust the pickup and delay settings without removing the cover.
Regulatory and compliance documentation
ABB provides the standard compliance package: RoHS and REACH declarations, UL file number, and IEC test reports on request. For a panel shop needing to document the SCCR or the interrupting rating, the datasheet and UL certificate are available with the order.