Siemens Power contactor, 3-pole, size S3, 1NO + 1NC, 37kW, 80A Part number 3RT2045-1AF00

Product Overview

The Siemens 3RT2045-1AF00 is a 3-pole power contactor from the SIRIUS 3RT2 family, size S3, designed for heavy-duty AC motor and load switching. It is rated for 80 A contact current and up to 37 kW at 400 V (AC-3), making it suitable for large motors and industrial applications. The unit includes 1 NO + 1 NC auxiliary contact, uses screw-terminal connections, and is controlled via a 110 V AC coil at 50 Hz.

Key Features

• SIRIUS 3RT2 series power contactor — size S3
• 3-pole main contacts for three-phase load switching
• Main contact rating: 80 A (AC-3), 37 kW / 400 V
• Auxiliary contacts: 1 NO + 1 NC — useful for control circuit, signalling or interlocks
• Screw-terminal connections — secure wiring for main and auxiliary circuits
• IEC/EN standard compliance for industrial motor switching applications
• Robust insulation and surge-voltage resistance for industrial environments
• Mechanical endurance — designed for very high number of switching cycles

Technical Specifications

• Article Number: 3RT2045-1AF00
• Contactor Size: S3
• Poles (Main Contacts): 3 (three-phase switching)
• Auxiliary Contacts: 1 NO + 1 NC
• Rated Main Current (AC-3): 80 A
• Rated Motor Power (400 V, AC-3): 37 kW
• Coil Voltage: 110 V AC, 50 Hz
• Insulation Voltage (main circuit): up to 1,000 V (pollution degree 3)
• Surge Voltage Resistance (main circuit): 8 kV
• Protection Class (front): IP20
• Mechanical Service Life (typical): 10,000,000 switching cycles

Compliance & Standards

• Part of Siemens SIRIUS 3RT2 industrial contactor family
• IEC/EN-compliant for motor switching (AC-3) and general load applications
• Insulation and surge-voltage specifications conform to industrial use standards

Applications

Ideal for controlling large three-phase motors, pumps, compressors, fans, conveyors, or other heavy industrial equipment. Suitable for motor-starter panels, switchgear, industrial machine control systems, and any application where high current capacity, reliable switching, and auxiliary contact signalling are required.