Siemens Power contactor, 3-pole, size S0, 2NO + 2NC, 25A Part number 3RT2026-1BB44

Product Overview

The Siemens 3RT2026-1BB44 is a 3-pole power contactor from the SIRIUS 3RT2 series, size S0. It is rated for 25 A contact current and up to 11 kW at 400 V (AC-3), making it suitable for motor and general AC load switching in industrial automation. This variant includes a removable auxiliary-contact block with 2 NO + 2 NC auxiliary contacts, and uses 24 V DC coil control — providing flexible control and signalling options for machine-starter or control-circuit applications.

Key Features

• SIRIUS 3RT2 series power contactor — size S0
• 3-pole main contacts for three-phase load switching
• Main contact rating: 25 A at 400 V AC (AC-3), 11 kW motor power
• Auxiliary contact block: 2 NO + 2 NC — enabling multiple control/signalling functions
• 24 V DC coil — compatible with standard DC control circuits
• Removable auxiliary-contact block — simplifies maintenance and wiring changes
• Screw-terminal connections for secure wiring
• Compact size (S0) — saves space in control cabinets or motor-starter panels
• Insulation voltage 690 V, surge-voltage resistance 6 kV — robust for industrial environments
• Mechanical endurance: up to 10 000 000 switching cycles — long operational life

Technical Specifications

• Article Number: 3RT2026-1BB44
• Product Type: Power contactor (3-pole, S0)
• Main Contact Rating (AC-3, 400 V): 25 A, 11 kW motor load
• Auxiliary Contacts: 2 NO + 2 NC (removable block)
• Coil Voltage: 24 V DC
• Insulation Voltage: 690 V
• Surge Voltage Resistance (main/aux): 6 kV
• Connection Type: Screw terminals for main and auxiliary circuits
• Contactor Size: S0
• Rated Operational Current: 25 A
• Mechanical Life (typical): 10,000,000 switching cycles
• Ambient Operating Temperature: –25 °C … +60 °C
• Pollution Degree: 3 (industrial environment suited)
• Mounting: DIN-rail or panel mount as per SIRIUS 3RT2 design

Compliance & Standards

• Part of Siemens SIRIUS 3RT2 industrial contactor range — IEC/EN compliant for motor switching and general load control
• Insulation and surge-voltage ratings comply with industrial use requirements for electrical safety
• Auxiliary-contact block removable according to standard contactor modular design — suitable for maintenance or control-circuit modifications

Applications

The 3RT2026-1BB44 is ideal for switching three-phase motors, pumps, fans, compressors, or general industrial loads up to 11 kW / 25 A. Its multiple auxiliary contacts make it suitable for control circuits requiring signalling, interlocks, or multiple outputs in machine-starter assemblies. The compact S0 size and reliable DC-coil control make it a solid choice for industrial machinery, automation panels, HVAC systems, and retrofit applications in control cabinets with limited space.