Iu 250 A — continuous current rating for the XT4 frame
The 1SDA068173R1 is a breaking part for the ABB XT4 molded-case circuit breaker platform, rated for a continuous current Iu of 250 A. This is the current the main contacts can carry without exceeding the temperature rise limits of the XT4 frame — sized for feeder or motor branch circuits up to that ampacity. The breaking part is the service-replaceable internal assembly — the arc chamber, contacts, and mechanism — not the complete breaker with the case and terminals. It fits into the XT4N 250 frame, 3-pole, with front-connection (F F) terminals.
Icu 36 kA at 415 V — short-circuit breaking capacity
The ultimate short-circuit breaking capacity Icu is 36 kA at 415 V AC. This is the maximum prospective fault current the breaking part can safely interrupt once without damage — a key figure for the panel designer's selective coordination study. At 690 V the Icu will be lower (per the ABB XT4 curve), but the 36 kA at 415 V covers most industrial 400 V distribution. Rated voltage is 690 V AC, rated frequency 50/60 Hz, so the part is suitable for global mains supplies. The 3-pole configuration handles three-phase circuits.
Lifecycle and sourcing — current production, no direct replacement
Sourced to order against the BOM quantity. Availability and current pricing are confirmed at RFQ through independent distribution channels. The 1SDA068173R1 is a fast-moving spare for installed XT4 panels — keep one on the shelf if the plant runs multiple XT4 breakers.