Siemens Contactor, aux, spring-loaded, 2NO+2NC, 5.5kW, 24VDC Part number 3RT2024-2BB44-3MA0

Product Overview

The Siemens SIRIUS power contactor 3RT2024-2BB44-3MA0 is a compact size S0, three-pole device designed for motor switching and industrial load applications. It supports up to 12 A in AC-3/AC-3e duty (5.5 kW at 400 V), has a 24 V DC coil, and includes 2 NO + 2 NC auxiliary contacts for enhanced control and signalling.

Key Features

• Rated Current: 12 A (AC-3/AC-3e) — up to 5.5 kW at 400 V
• Poles: 3 main poles for three-phase load switching
• Coil Voltage: 24 V DC for control circuit operation
• Auxiliary Contacts: 2 NO + 2 NC for monitoring and signalling functions
• Spring-loaded or screw terminals: Flexible wiring options (spring or screw depending model variant)
• Size S0 Frame: Compact footprint suited to space-constrained control cabinets
• High Insulation & Surge Resistance: Insulation voltage 690 V, surge in main circuit 6 kV
• Durable Design: Mechanical service life up to 10 000 000 switching cycles

Technical Specifications

• Product Series: SIRIUS 3RT2 power contactors
• Rated Operational Current (AC-3/AC-3e): 12 A
• Motor Power Rating: 5.5 kW at 400 V
• Number of Poles: 3
• Coil Supply Voltage: 24 V DC
• Auxiliary Contacts: 2 NO + 2 NC
• Insulation Voltage (Ui): 690 V
• Surge Withstand Voltage: 6 kV
• Mechanical Service Life: Up to 10 000 000 operations
• Mounting: Snap-on or screw mounting onto 35 mm DIN rail (EN 60715) or panel mounting
• Frame Size: S0
• Ambient Operating Temperature: –25 °C to +60 °C* *(Typical range for S0 contactors)
• Country of Origin: Germany

Compliance & Certifications

• CE Marking: Conforms with EU Low-Voltage and Machinery Directives
• RoHS Compliant: Meets Siemens restricted-substance policy since 01.10.2009
• WEEE Take-Back: Obligations apply in applicable regions
• Standards: Designed according to IEC/EN 60947 (main and auxiliary contactors)

Applications

Ideal for switching and controlling three-phase motors and industrial loads in automation installations, control panels, and machine tool environments. Commonly used in conveyor systems, pumps, fans, HVAC installations and manufacturing plant automation requiring compact, robust and reliable contactor modules.