Rated current and thermal derating
The 3RW4037-1TB04: At 40 °C ambient the soft starter delivers 63 A continuous. Derate to 58 A at 50 °C and 53 A at 60 °C — the derating curve matters when the panel internal temperature runs above 40 °C, which is common in a closed enclosure with multiple drives. The integrated bypass contact system carries the motor current after start, removing the thyristors from the power path and reducing heat dissipation in the enclosure during run.
Mounting and panel clearances
Fastening method is screw and snap-on mounting — snaps onto a DIN rail or screws directly to the backplate. The device footprint is 55 mm wide, 160 mm high, 170 mm deep. Required clearances: 60 mm above, 40 mm below, 30 mm at the side. These gaps ensure airflow for the thyristor cooling fins; crowding them derates the current further.