Siemens Power contactor, 3-pole, 1NO + 1NC, size S0,400V, 18.5kW, 38A Part number 3RT2028-1AN20

Product Overview

The Siemens 3RT2028-1AN20 is a high-performance power contactor from the SIRIUS 3RT2 series, designed for three-pole AC motor switching applications. It supports current ratings up to 38 A (AC-3) and covers a power rating of roughly 18.5 kW at 400 V, making it suitable for compact motor control systems and automation installations.

Key Features

• 3-pole power contactor (size S0) with screw terminal connection
• Rated for AC-3 duty: 38 A at 400 V and approximately 18.5 kW at 400 V
• Auxiliary contacts: 1 normally open (NO) + 1 normally closed (NC) standard configuration
• Designed for AC-3e / AC-3 operation in machinery and industrial motor starter applications
• Compact, rugged design with a high service life and wide ambient temperature range (–25 °C to +60 °C)

Technical Specifications

• Product Series: Siemens SIRIUS 3RT2 Power Contactors
• Article Number: 3RT2028-1AN20
• Contactor Size: S0
• Main Poles: 3
• Auxiliary Contacts: 1 NO + 1 NC
• Rated Operational Current (AC-3): 38 A at 400 V
• Rated Power (AC-3, 400 V): ~18.5 kW
• Rated Insulation Voltage (Ui): 690 V
• Rated Impulse Withstand Voltage (Uimp): 6 kV
• Ambient Temperature (Operating): –25 °C to +60 °C
• Weight (Approx.): 0.426 kg
• Mounting Altitude Max: 2 000 m above sea level

Compliance & Certifications

• Designed under Siemens industrial-automation quality standards for contactors
• Conforms to IEC / EN standards for low-voltage motor switching devices
• RoHS-compliant and suitable for global industrial installations

Applications

The 3RT2028-1AN20 contactor is ideal for use in control panels, motor starter units and automation systems where moderate-power three-phase motors (up to ~18.5 kW) need reliable, compact switching. Its size-S0 form, standard auxiliary contacts and wide temperature capability make it suitable for manufacturing machines, HVAC units and industrial feeders.