Siemens Power contactor, 2NO+2NC, 24VDC, 15kW/400V Part number 3RT2027-1BB44

Product Overview

The Siemens 3RT2027-1BB44 is a 3-pole power contactor from the SIRIUS 3RT2 family. With a 24 V DC control coil and rated for up to 32 A at 400 V AC, it is designed for switching three-phase motors or other AC loads. Its compact “S0” size, built-in auxiliary contacts and robust construction make it well suited for industrial motor control and automation systems.

Key Features

• 3-pole power contactor (main contacts for three-phase switching)
• Rated for 32 A contact current — suitable for motors and general AC loads
• Rated motor power up to 15 kW at 400 V (AC-3 / AC-3e operation) — for standard motor duty
• Control coil: 24 V DC — compatible with common PLC / control-voltage supplies
• Auxiliary contacts: 2 NO + 2 NC — for signalling, interlocking, feedback or control-logic extension
• Screw-terminal wiring — simplifies secure electrical connection
• Size S0 — compact form factor, suitable for control cabinets or motor-starter assemblies
• Insulation voltage rating up to 690 V; surge-voltage resistance up to 6 kV — suitable for industrial environments
• Mechanical lifespan rated for many switching cycles — good for frequent operation

Technical Specifications

• Article Number (MLFB): 3RT2027-1BB44
• Product Family / Type: SIRIUS 3RT2 — 3-pole power contactor
• Poles (Main Contacts): 3
• Rated Contact Current (Ie): 32 A (AC-3 / AC-3e duty)
• Rated Motor Power (AC-3 / AC-3e): 15 kW @ 400 V
• Control Coil Voltage: 24 V DC
• Auxiliary Contacts: 2 NO + 2 NC
• Terminal Type: Screw terminals (main and auxiliary circuits)
• Insulation Voltage: 690 V (main and auxiliary circuits) — pollution degree 3
• Surge Voltage Withstand: 6 kV (main and auxiliary circuits)
• Contactor Size: S0 (compact housing)
• Intended Operation: AC-3 / AC-3e three-phase motor/control loads
• Mounting: Standard DIN-rail or panel / cabinet mounting as typical for contactors

Applications

The 3RT2027-1BB44 is ideal for controlling medium-power three-phase motors, industrial machines, pumps, compressors, conveyor drives, HVAC systems, and other AC loads. Its auxiliary contacts allow integration into control circuits for interlocking or signalling. The compact size and robust rating make it suitable for motor starter assemblies, control panels, and automation systems in manufacturing, processing or building services environments.