3RW4055-6BB44 Siemens SIRIUS Soft Starter Industrial Motor Controller

Siemens 3RW4055-6BB44 SIRIUS Soft Starter Technical Overview

• Siemens 3RW4055-6BB44 operates at a rated voltage of 200 to 460 V AC. It supports a frequency range of 50 to 60 Hz. The device draws a rated operating current of 134 A at 40 °C.
• At 50 °C ambient temperature, the operating current rating drops to 117 A. At 60 °C, it provides 100 A continuously. This derating characteristic ensures stable performance in warm conditions.
• For a 400 V motor, the 3RW4055-6BB44 delivers 75 kW of mechanical power. At 230 V, it provides 37 kW. The UL rating shows 40 hp at 220/230 V and 75 hp at 460/480 V.
• The control supply voltage is 230 V AC at both 50 Hz and 60 Hz. It tolerates a -15% to +10% voltage variation. The control electronics use screw-type terminals for secure wiring.
• This soft starter measures 250 mm in depth, 120 mm in width, and 198 mm in height. Its size class is S6. You must mount it with screws on a vertical surface.
• Installation requires 100 mm free space above the device. Leave 75 mm below and 5 mm on each side for proper cooling. The maximum cable length reaches 300 meters.
• The main circuit uses box terminals for busbar or cable connections. You can connect finely stranded wires from 16 to 70 mm². AWG conductors from 6 to 2/0 are also compatible.
• Auxiliary contacts include two NO contacts and one CO contact. They use screw terminals for solid or finely stranded wires (0.5 to 2.5 mm²). The device has no NC contacts.
• The operating temperature ranges from -25 °C to +60 °C. Storage temperature tolerates -40 °C to +80 °C. Protection class is IP00, so you need an external enclosure.
• Active power loss at 40 °C operating current is typically 60 W. The continuous operating current capacity reaches 115% of Ie. Minimum motor load is 20% of the rated current.
• You can reset the device externally after a fault. A red LED shows fault signals clearly. The unit does not support thermistor motor protection or inside-delta circuits.

Frequently Asked Questions (FAQ)

• Q: Do you have this soft starter in stock?
  A: Yes, we maintain local stock of the 3RW4055-6BB44. Most orders ship within 5 business days after payment confirmation.
• Q: Which shipping carriers do you use?
  A: We ship via FedEx, UPS, and DHL. You can choose your preferred carrier at checkout. All shipments include tracking numbers.
• Q: What is the return policy for this product?
  A: We support returns within 30 days of delivery. The 3RW4055-6BB44 must remain unused and in original packaging. Contact us before returning any item.
• Q: Can I use this soft starter for a 460 V motor?
  A: Yes, the 3RW4055-6BB44 operates at 200-460 V AC. At 460/480 V, it delivers 75 hp as per UL ratings. Check your motor's full load current first.
• Q: Does the device require an external bypass contactor?
  A: No, the 3RW4055-6BB44 has an integrated bypass contact system. This feature reduces heat and saves energy during continuous running.

Email: sales@nex-auto.com
WhatsApp: +86 153 9242 9628

Partner: NexAuto Technology Limited