Siemens SIRIUS 3RT2025 S0 3-Pole Power Contactor 24V DC

Technical Overview

3-pole S0 power contactor, 17A (AC-3, 400V), 24V DC coil, 1 NO + 1 NC aux contacts. Ideal for motor control.

Key Features

3-pole power contactor, size S0 for space-saving installation.
Rated current of 17 A (AC-3, 400 V) and operating power of 7.5 kW (AC-3, 400 V).
Operated by a 24 V DC control voltage coil.
Integrated 1 normally open (NO) and 1 normally closed (NC) auxiliary contacts.
Equipped with screw terminals for secure and reliable electrical connections.
High mechanical service life of 10,000,000 operating cycles.
Wide operating temperature range from -25 °C to +60 °C.
Maximum operational voltage of 690 V AC.
Protection class IP20 on the front.
Coil closing and holding power of 5.9 W.

Technical Specification Matrix

Parameter	Value
Contactor Size	S0
Number of Poles	3
Rated Current (AC-3, 400 V)	17 A
Rated Current (AC-1, 400 V, 40°C)	40 A
Operating Power (AC-3, 400 V)	7.5 kW
Operating Power (AC-3, 690 V)	11 kW
Rated Voltage (max operational)	690 V AC
Control Supply Voltage (Coil)	24 V DC
Coil Closing and Holding Power	5.9 W
Auxiliary Contacts	1 NO + 1 NC
Terminal Type	Screw terminal
Insulation Voltage (main and auxiliary)	690 V
Surge Voltage Resistance	6 kV
Mechanical Service Life	10,000,000 operating cycles
Operating Temperature	-25 °C to +60 °C
Storage Temperature	-55 °C to +80 °C
Maximum Installation Altitude	2,000 m
IP Rating (on the front)	IP20
Physical Weight (kg)	0.6
Dimensions L x W x H (cm)	9.2 x 5.4 x 11.5

Industrial Applications

1. Motor Control for Industrial Conveyor Systems

This contactor can precisely control the start and stop of three-phase induction motors up to 7.5 kW (at 400V) driving conveyor belts in manufacturing or logistics facilities. The 24V DC coil allows direct interfacing with PLC systems for automated control, and the integrated auxiliary contacts provide feedback or interlocking for safety and sequence control.

Problem Solved

Enables reliable and frequent switching of motors in automated material handling, preventing motor damage from improper switching sequences and integrating seamlessly into modern control architectures.

Three-phase motorconveyorPLC controlinterlockingautomated material handling7.5 kW24 V DC

2. HVAC System Fan Control in Commercial Buildings

The 3RT2025-1BB40 is suitable for switching fans in large commercial HVAC systems. Its 17A current rating and 690V max operational voltage accommodate typical industrial fan motor requirements. The durable mechanical lifespan ensures longevity in systems that require frequent on/off cycles throughout the day, while the IP20 rating is adequate for enclosed panel installations.

Problem Solved

Provides robust and long-lasting switching for critical ventilation and air circulation fans, contributing to stable indoor climate control and reducing maintenance frequency in demanding commercial environments.

HVACfan motorventilation17 A690 V ACfrequent switchingIP20

3. Pump Control in Water Treatment Plants

In water treatment applications, this contactor can manage the operation of pumps for water intake, circulation, or wastewater processing. The 3-pole design handles the three-phase pump motors, and the 24V DC coil is ideal for control by a central SCADA or PLC system, allowing for precise control of fluid movement. The screw terminals offer reliable connections against vibrations.

Problem Solved

Offers dependable control for essential pump motors in critical infrastructure, ensuring continuous operation and protecting motors from overcurrents when paired with an overload relay.

Pump controlwater treatmentSCADAPLCthree-phase motorsfluid managementscrew terminals