The TA25DU14 is a thermal bimetallic overload relay rated at 14 A continuous, adjustable down to 10 A via the dial on the front face. The three-pole design tracks current imbalance across all phases; if one leg pulls ahead, the differential trip catches it before the motor sees sustained single-phasing. It mounts directly to ABB A-Line contactors in the A/AE/AL9 through A/AE/AL40 frame range. The interface is a snap-on mechanical linkage — no separate wiring between the contactor and the overload block. Selectable manual or automatic reset gives the panel builder flexibility: auto for remote or unattended sites, manual for a line where you want an operator to clear the fault before restarting.
The 14 A rating is the maximum continuous current the relay can carry without tripping. In practice, you set the dial to the motor's full-load amps — if the motor nameplate says 12.5 FLA, you dial to 12.5, not 14. The 10–14 A range covers NEMA frame sizes 56 through 184T on typical 460 V three-phase motors. Trip Class 10 is standard for general-purpose pumps, fans, and compressors; if you have a high-inertia load (a centrifuge or a large flywheel), you might step up to Class 20, but that would be a different relay family. The NEMA type designation means the overload follows NEMA ICS 2 sizing conventions rather than IEC 60947-4-1. The practical difference: NEMA overloads are generally selected by the motor's service-factor amps rather than the exact FLA, giving a bit more headroom on continuous duty. For a panel built to UL 508A, this is the expected style.