Siemens 3RW4427-1BC44 Soft Starter – High Power SIRIUS Series 90kW

Siemens 3RW4427-1BC44 SIRIUS Soft Starter Overview

The 3RW4427-1BC44 from Siemens is a high-performance SIRIUS soft starter engineered for smooth motor starts and efficient torque control. Designed for heavy-duty applications, it supports both standard and inside-delta connections. Author: Powergear X Automation

Main Performance Features

• Rated current: 93 A (standard), 161 A (inside-delta) at 40 °C.
• Power rating: 45 kW (standard) / 90 kW (inside-delta) at 400 V.
• Voltage range: 200 – 460 V AC main, 230 V AC control supply.
• Frequency: 50/60 Hz, with ±10% tolerance.
• Power loss: only 55 W at rated operation, ensuring energy efficiency.

Electrical and Functional Design

• Built-in thyristors and integrated bypass reduce heat and energy waste.
• Adjustable start and stop current limit to protect motor windings.
• Motor brake output enhances stopping performance in high inertia systems.
• Supports inside-delta connection for higher power in compact space.
• Includes intrinsic and overload protection, plus thermistor evaluation.

Key Technical Data

• Operating current at 50 °C: 82 A (standard), 142 A (inside-delta).
• Operating current at 60 °C: 72 A (standard), 125 A (inside-delta).
• Motor power at 230 V: 22 kW (standard), 45 kW (inside-delta).
• UL/CSA performance: 25 hp @ 208 V, 60 hp @ 460 V (inside-delta).
• Minimum adjustable motor current: 18 A.

Construction and Dimensions

• Size: 170 mm (W) × 192 mm (H) × 270 mm (D).
• Mounting: screw fixing, rotatable ±90°, tilt ±22.5°.
• Protection: IP00, durable metal terminal housing.
• Altitude: up to 5000 m without derating.
• Ambient temperature: operation up to +60 °C, storage −25 °C to +80 °C.

Connection Terminals

• Main terminals: box type, front and back clamping points.
• Conductor sizes: 2.5–70 mm² (solid or stranded), AWG 10–2/0.
• Auxiliary circuit: 3 NO + 1 CO contacts, screw type.
• Control wiring: 2x (0.5–2.5 mm²) solid, 2x (0.5–1.5 mm²) stranded.

Environmental and Mechanical Endurance

• IEC 60721 categories: 3K6 / 3C3 / 3S2 / 3M6 – resistant to dust, no condensation or salt mist.
• Spacing for ventilation: top 100 mm, side 5 mm, bottom 75 mm.
• Wire length support up to 500 m.

Top Selling Points

• Powerful control for large motors up to 90 kW inside-delta.
• Compact body fits standard control panels easily.
• Energy-saving design with reduced thermal loss.
• Easy diagnostics through built-in fault display.
• High reliability with long service life in harsh conditions.

Warranty & Shipping Information

• Warranty: 12 months for all Siemens SIRIUS soft starters.
• Fast global delivery via FedEx, UPS, and DHL.
• Every unit tested before shipment for full quality assurance.

FAQ

• Q: Can the 3RW4427-1BC44 be used in humid conditions?
  A: Yes, provided it’s installed in a dry cabinet without condensation.
• Q: What is the benefit of using the inside-delta circuit?
  A: It allows higher motor power with smaller wiring and device size.
• Q: Does it include motor brake control?
  A: Yes, it includes a motor brake output for fast deceleration.
• Q: How can I reset the device after overload trips?
  A: Use the external reset terminal or manual reset on the device.
• Q: What is the power loss compared to other models?
  A: Only 55 W typical at full load, making it more efficient than older starters.

Contact Information

• Email: sales@powergearx.com
• WhatsApp: +86 18030005825

Original Source: https://www.powergearx.com/

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