Current ratings that govern the motor load
The 3RW4457-6BC35: Rated 1524 A at 40 °C, derating to 1351 A at 50 °C and 1200 A at 60 °C. The 40 °C figure is the base rating; for every degree above that, the available current drops. In a 50 °C panel ambient, budget 1351 A continuous — the 1524 A nameplate applies only at or below 40 °C. Insulation voltage rated 690 V, operating frequency 50/60 Hz.
Integrated bypass and inside-delta wiring
The integrated bypass contact system removes the thyristors from the circuit after the start completes, eliminating heat dissipation in the power section during run. This is the standard topology for soft starters above 100 A — the bypass carries the continuous current, not the silicon. Inside-delta circuit capability means the starter can be wired between the motor windings rather than in the supply lines, reducing the current through each power pole to 58% of the line current. This effectively extends the motor current range the same frame can handle — a 1524 A line-rated starter covers motors up to roughly 2600 A in inside-delta configuration.
Protection set and overload handling
Motor overload protection, intrinsic device protection, and adjustable current limitation are all onboard. The minimum load setting is 8% of the rated current — useful for light-load starts or pump soft-fill sequences where the breakaway torque is low. External reset input and a display for fault signals are standard. The display shows the fault code directly, reducing troubleshooting time on the panel door.
Mounting and panel integration
Mounting position allows vertical surface installation with +/-90° rotation and +/-22.5° tilt front-to-back. This is not a fixed-orientation device — the panel layout can rotate the unit without derating, as long as the tilt limits are respected. Dimensions: 510 mm wide, 640 mm high, 290 mm deep. Clearance requirements: 100 mm above, 75 mm below, 5 mm at the sides. The side clearance is tight — adjacent devices can sit close, but the vertical airflow path needs the full 100/75 mm free space for natural convection cooling. The main current circuit connection uses busbar connection; the main cable range accepts stranded 70–240 mm², finely stranded 50–240 mm², or AWG 2/0–500 kcmil.
Environmental and compliance
Degree of pollution 3 per IEC 60947-4-2 — conductive pollution occurs, or dry non-conductive pollution that becomes conductive due to condensation. This is the standard industrial environment rating; no additional conformal coating is required for normal factory-floor conditions. Storage temperature range -25 to +80 °C; operation up to 60 °C ambient. Maximum motor cable length is 500 m — longer runs may require output reactors to manage reflected wave voltage spikes on the motor terminals.