Current rating and thermal derating — the real operating envelope
The 3RW3003-1CB54: Rated 3 A at 40 °C, derating to 2.6 A at 50 °C and 2.2 A at 60 °C. The derating curve is the binding constraint for panel ambient temperature — if the enclosure runs at 50 °C, budget 2.6 A continuous, not the 40 °C figure. Minimum load threshold is 9 % of the rated current — below that the soft starter may not trigger the thyristors reliably. For a 3 A unit, that means the motor draw must stay above 0.27 A at the control point.
Control supply and wiring — wide-range simplifies BOM
Dual-wire entry on main contacts accepts 2×(0.5–2.5 mm²).
22.5 mm wide — fits standard 35 mm DIN rail with screw or snap-on fastening. Mounting position allows ±10° rotation and ±10° tilt forward/back from vertical. Depth is 123 mm, height 102 mm. Pollution degree 3 per IEC 60947-4-2 — rated for conductive dust and condensation typical in industrial control panels. Operating temperature range -25 to +60 °C, storage -40 to +80 °C.
Lifecycle and sourcing — active, quoted to order
No integrated bypass contact, no motor overload protection, no adjustable current limitation — this is a basic soft starter for simple ramp-start applications. The thyristor output handles the start transient; external overload relay is required.