TeSys U advanced control unit for motor protection and control
It provides manual reset, protection against overload, short-circuit, phase failure, phase imbalance, and earth fault. The unit is rated for motor power up to 7.5 kW at 400...440 V AC, 9 kW at 500 V AC, and 15 kW at 690 V AC, all at 50/60 Hz. It operates with a control circuit voltage of 110...240 V AC or 110...220 V DC.
The 7.5 kW rating at 400 V AC tells you this unit directly matches a standard 7.5 kW IEC motor on a 400 V three-phase supply — no external overload relay needed. The utilisation categories AC-41, AC-43, and AC-44 cover resistive loads, squirrel-cage motors with starting currents up to 6× Ir, and more severe duty cycles like frequent starting or plugging. The tripping threshold of 14.2 × Ir ± 20 % sets the magnetic short-circuit release point, so it clears a bolted fault fast without nuisance tripping on normal motor inrush.
The LUCB18FUTQ mounts via plug-in (front face) into a TeSys U power base or starter. IP20 on the front panel and wired terminals keeps it safe for enclosed panel use; IP40 on the front panel outside the connection zone adds a bit more splash protection. The TH protective treatment per IEC 60068 means it's coated for humid or mildly corrosive environments.
The unit carries approvals to EN 60947-6-2, IEC 60947-6-2, UL 60947-4-1 (with phase barrier), and CSA C22.2 No 60947-4-1 (with phase barrier). Safe separation of circuits is maintained at 400 V SELV between control/auxiliary and main circuits. It withstands 2 kV common mode and 1 kV serial mode non-dissipating shock waves, 4 kV fast transients on all circuits except serial link, and radiated fields up to 10 V/m.