The 3RW4037-1TB05: That 40 °C baseline is the typical panel ambient; if your enclosure runs hotter, size up or plan for the derate. The integrated bypass contact carries the motor current at full speed, pulling the thyristors out of circuit — no external bypass contactor needed, and the heat load in the panel drops once the motor is up to speed.
S2 frame — panel fit and mounting
S2 frame dimensions: 55 mm wide, 160 mm high, 170 mm deep. That 55 mm width is a single 3-module DIN-rail slot — fits in a standard distribution board without eating adjacent positions. Mounting is screw or snap-on. The mounting position is flexible — vertical surface with up to ±90° rotation with an additional fan, or ±10° without. Keep the clearance: 60 mm upwards, 40 mm downwards, 30 mm at the side for airflow and wiring access.
Motor protection and control built in
Motor overload protection is integrated — no separate overload relay needed. Adjustable current limitation lets you set the starting torque profile between 20% and the full rated current. Intrinsic device protection covers the soft starter itself against overtemperature and phase imbalance. The red fault signal display gives a visual trip indication on the front panel. External reset input allows remote fault reset from a PLC or pushbutton — keeps the operator away from the panel door during a restart sequence.
Wiring and environment
Auxiliary contact terminals take 2x (20 … 14) AWG. Maximum motor cable length is 300 m — within typical industrial runs, but check for reflected-wave risk on long feeders. Insulation voltage rated 600 V.