Siemens Power contactor, screw terminal, 4Kw, 400VAC, 24VDC Part number 3RT2023-1KB40

Product Overview

The Siemens 3RT2023-1KB40 is a compact SIRIUS 3RT-series 3-pole power contactor (size S0) with a 24 V DC control coil and integrated varistor. It is designed for reliable switching of three-phase motors and loads up to 4 kW at 400 V AC. Its compact size, PLC-compatible coil and robust screw terminal connections make it ideal for use in industrial control cabinets and motor starter assemblies.

Key Features

• 3-pole power contactor, size S0
• Rated AC-3/AC-3e operational current: 9 A
• Motor switching capacity: 4 kW at 400 V (AC-3)
• 24 V DC control coil, suitable for PLC outputs
• Wide control voltage range: 0.7 – 1.25 × Uc
• Plug-in varistor for coil surge suppression
• Integrated auxiliary contacts: 1 NO + 1 NC
• Screw terminals for main and auxiliary circuits
• Compact S0 frame size for space-saving installations
• No additional auxiliary switch can be added

Technical Specifications

• Article Number: 3RT2023-1KB40
• Product Family: SIRIUS 3RT power contactors
• Frame Size: S0
• Number of Poles: 3
• Main Contact Configuration: 3 × NO
• Auxiliary Contacts: 1 NO + 1 NC (integrated)
• Rated Operational Current (AC-3 / AC-3e): 9 A
• Rated Motor Power (AC-3 at 400 V): 4 kW
• Rated Operational Voltage: up to 690 V AC
• Control Voltage: 24 V DC
• Control Voltage Range: 0.7 … 1.25 × Uc
• Coil Suppression: Plug-in varistor
• Insulation Voltage (Ui): 690 V
• Impulse Withstand Voltage (Uimp): 6 kV
• Mechanical Service Life: approx. 10,000,000 switching cycles
• Electrical Endurance (AC-3): approx. 1,000,000 cycles
• Connection Type: Screw terminals
• Mounting: DIN-rail or direct panel mounting
• Ambient Operating Temperature: −25 °C … +60 °C
• Storage Temperature: −40 °C … +80 °C
• Protection Class: IP20
• Net Weight: approx. 0.34 kg

Compliance & Certifications

• Designed and manufactured according to IEC / EN standards for low-voltage contactors
• Suitable for PLC outputs and electronic control systems
• Integrated surge suppression for industrial control environments
• Designed for industrial, commercial, and automation applications

Applications

The Siemens 3RT2023-1KB40 is ideal for controlling three-phase motors and electrical loads in industrial automation systems. Typical applications include motor starters for pumps, fans, conveyors, compressors, and machine tools. Thanks to its compact S0 frame, PLC-compatible DC coil, and built-in auxiliary contacts, it is well suited for modern automation control panels, OEM machinery, and high-density motor control centers.