Motor branch circuit protection with an MA trip
The 1SDA068114R1 is an ABB SACE Tmax XT4N 160 frame MCCB with a magnetic-only (MA) trip unit set at In=20 A. The MA trip responds only to short-circuit and high overcurrents — it has no thermal element, so motor overload protection must be provided by a separate overload relay in the branch circuit. The frame rating Iu=160 A means the breaker's internal bus and contacts are sized for 160 A continuous, but the trip threshold is set by the installed MA module to 20 A. This lets the same frame cover a wide range of motor FLA settings by swapping the trip unit.