Siemens Power contactor, 3-pole, size S00, 1NC, 7.5kW, 16A Part number 3RT2018-1BB42

Product Overview

The Siemens 3RT2018-1BB42 is a 3-pole power contactor from the SIRIUS 3RT2 series, size S00. It is designed for switching three-phase AC motors and other industrial loads, combining compact dimensions with reliable switching capacity. With a 7.5 kW motor power rating (at 400 V) and 16 A contact current, it is suitable for small motors and general AC load applications. The device includes a single auxiliary contact (1 NC) and uses screw-type terminals for secure wiring. Its compact size and strong switching performance make it well suited for control cabinets, motor starters, and automation systems.

Key Features

• SIRIUS 3RT2 series, size S00, 3-pole power contactor
• Main contact rating: 16 A, 400 V AC
• Motor power rating (AC-3, 400 V): 7.5 kW
• Single auxiliary contact: 1 NC — useful for interlocks, signalling or control logic
• Screw-type main and auxiliary terminals — secure wiring suitable for industrial environments
• Compact dimensions: width 45 mm — fits small control panels / motor starters
• Standard 3-pole config — compatible with three-phase motors and load circuits
• Compliant with SIRIUS / IEC contactor standards for safe and reliable switching in industrial systems

Technical Specifications

• Article Number: 3RT2018-1BB42
• Contactor Size: S00
• Poles (main contacts): 3 (three-phase switching)
• Auxiliary Contacts: 1 NC (normally closed)
• Main Contact Rating: 16 A, 400 V AC
• Motor Power Rating (AC-3, 400 V): 7.5 kW
• Terminal Type: Screw terminals for main and auxiliary circuits
• Mounting / Housing: Standard DIN-rail / control-cabinet compatible (size S00 compact housing)
• Intended Use: Switching three-phase motors or AC loads, motor-starter applications, general load control

Compliance & Standards

• Part of Siemens SIRIUS 3RT2 contactor family — global standard for industrial switching devices
• Designed for AC-3 motor switching applications; meets relevant IEC/EN contactor standards
• Suitable for industrial control cabinets, motor feeders and automation systems requiring compact and reliable contactors

Applications

This contactor is ideal for controlling small to medium three-phase motors (e.g. pumps, fans, small compressors), lighting or general AC load circuits where up to 7.5 kW / 16 A switching is adequate. Its compact size (S00) makes it suitable for motor starters, control panels, machine cabinets, and retrofit installations with space constraints. The added auxiliary contact supports interlock or control logic tasks within automation systems.