Product Overview

Circuit breaker size S0 for motor protection, CLASS 10 A-release 18...25 A N-release 325 A Spring-type terminal Standard switching capacity

Key Features

• Size: S0 (45 mm width)
• Current Range: 18...25 A adjustable thermal overload release
• Short-circuit Release: 325 A (N-release)
• Trip Class: CLASS 10 according to IEC 60947-4-1
• Connection System: Spring-type terminal
• Switching Capacity: Standard switching capacity
• Number of Poles: 3-pole
• Rated Operational Voltage: Up to 690 V AC
• Rated Frequency: 50/60 Hz

Technical Specifications

Standards Compliance:

• IEC 60947-1, EN 60947-1 (VDE 0660 Part 100)
• IEC 60947-2, EN 60947-2 (VDE 0660 Part 101)
• IEC 60947-4-1, EN 60947-4-1 (VDE 0660 Part 102)
• UL 508 (UL 60947-4-1), CSA C22.2 No. 14 (CSA-C22.2 No. 60947-4-1)

Operating Conditions:

• Ambient Temperature: -20°C to +70°C (with current reduction above +60°C)
• Mounting Position: Any position according to IEC 60447
• Degree of Protection: IP20
• Touch Protection: Finger-safe according to DIN EN 50274
• Net Weight: 0.421 kg

Performance Features:

• Phase loss sensitivity for reliable motor protection
• Integrated overload and short-circuit protection
• Temperature compensation from -20°C to +60°C
• Test function for operational verification
• Isolating function according to IEC 60947-2
• Explosion protection approval for motors with "increased safety" type (EEx e)
• Short-circuit breaking capacity up to 55 kA at 400V AC

Spring-Type Terminal Connection System

Advanced Spring-Loaded Terminals:

• Tool Required: Ø 3.0 x 0.5 mm (3RA2908-1A)
• Tool-free Operation: No tightening torque required
• Vibration Resistant: Superior performance in high-vibration environments
• Temperature Independent: Consistent connection across temperature ranges
• Fast Installation: Reduced wiring time compared to screw terminals
• Reliable Connection: Permanent spring pressure ensures stable contact

Conductor Cross-sections:

• Solid and stranded: 2 x (1.0 to 10) mm²
• Finely stranded without end sleeve: 2 x (1.0 to 6.0) mm²
• Finely stranded with end sleeve: 2 x (1.0 to 6.0) mm²
• AWG cables: 2 x (18 to 8)
• Maximum outer diameter of conductor insulation: 3.6 mm

Applications

• Motor protection for three-phase motors (20-30 HP range)
• Overload and short-circuit protection for high-power applications
• System protection applications
• Load feeder protection in high-vibration environments
• Control circuit switching
• Suitable for motors with rated currents between 18-25 A
• Industrial automation and process control applications
• Manufacturing and production line equipment
• Heavy-duty industrial applications with vibration concerns
• Large conveyor systems and industrial machinery
• High-capacity pump, fan, and compressor applications
• Mobile equipment and transportation applications

Spring Terminal Advantages

Operational Benefits:

• Faster Installation: Up to 50% reduction in wiring time
• Maintenance-Free: No retightening required over time
• Vibration Proof: Maintains connection integrity in demanding environments
• Temperature Stable: Consistent performance across temperature cycles
• Corrosion Resistant: Enhanced long-term reliability
• Easy Conductor Removal: Simple push-button release mechanism

Cost Benefits:

• Reduced Labor Costs: Faster installation and maintenance
• Lower Downtime: Reliable connections reduce maintenance intervals
• Extended Service Life: Superior connection stability
• Improved Safety: Reduced risk of loose connections

Accessories Available

• Auxiliary switches (transverse and lateral)
• Signaling switches for status monitoring
• Auxiliary releases (undervoltage and shunt)
• Disconnector modules
• Door-coupling rotary operating mechanisms
• Enclosures and mounting accessories
• Link modules for contactor integration
• 3-phase busbar systems
• Sealable covers for tamper protection
• Phase barriers for enhanced safety

Installation

• Mounting: 35 mm DIN rail according to DIN EN 60715 or screw mounting
• Clearance Requirements: 30 mm from grounded or live parts
• Connection: Spring-loaded terminals for quick and secure wiring
• Modular System: Compatible with SIRIUS 3RT2 contactors and accessories
• Package Dimensions: 52.50 x 133.00 x 106.50 mm
• Snap-on mounting for easy installation and removal
• Side-by-side mounting capability

Compliance & Environmental

• Country of Origin: Germany
• RoHS Compliance: Since 01.10.2009
• WEEE Compliance: Take-back obligation applies
• REACH Regulation: Contains lead titanium zirconium oxide in concentrations >0.1% w/w
• UL/CSA Approvals: Available for North American applications
• ATEX Approval: For hazardous area applications
• Product Class: A - Standard product, stock item with return guidelines

Quality & Reliability

• Manufactured in Germany with strict quality control
• Long-term stability with proven bimetal technology
• Mechanical endurance: 100,000 operating cycles
• Electrical durability: 100,000 operating cycles
• Maximum switching frequency: 15 starts per hour
• Current-limiting characteristics for enhanced protection
• Vibration and shock resistance according to IEC 60068-2-27
• Enhanced connection reliability with spring terminals

Motor Protection Benefits

• Prevents motor damage from overload conditions
• Protects against phase loss and unbalanced loads
• Reduces downtime with reliable trip characteristics
• Extends motor life through precise current monitoring
• Suitable for standard and energy-efficient IE3 motors
• Optimized for side-by-side installation in control panels
• Superior N-release rating (325A) for high-power applications
• Enhanced connection reliability in challenging environments

Design Features

• Advanced spring-loaded terminal design for industrial environments
• Clear current setting scale for easy adjustment (18-25A range)
• Integrated test function for maintenance verification
• Compact 45mm width for space-efficient installation
• Lockable rotary operating mechanism
• Visual trip indication for quick fault identification
• Enhanced short-circuit protection with 325A N-release
• Tool-free conductor insertion and removal

High-Power Applications

• Designed for larger industrial motors and equipment
• Enhanced short-circuit protection with 325A N-release
• Ideal for applications requiring higher current ratings (18-25A)
• Suitable for continuous operation in demanding environments
• Optimized for IE3 energy-efficient motors
• Enhanced protection for high-value industrial equipment
• Perfect for heavy-duty applications requiring robust protection
• Suitable for motors up to 30 HP at 480V
• Ideal for high-vibration environments

Advanced Protection Features

• Extended Current Range: 18-25A suitable for large motors
• Superior Short-Circuit Protection: 325A N-release for maximum safety
• Optimized for IE3 Motors: Specially adapted for energy-efficient motors
• Reliable Trip Characteristics: CLASS 10 tripping for consistent performance
• Temperature Compensated: Stable operation across wide temperature ranges
• Phase Loss Detection: Protects against unbalanced load conditions
• Magnetic Trip Elements: Fast response to short-circuit conditions
• Bimetallic Overload Protection: Accurate thermal protection for motors
• Spring Terminal Technology: Enhanced connection reliability

Download existing graphical data for this product:

• Technical Data Sheet
• Dimension Drawings
• Wiring Diagrams
• CAD Data
• 3D Models
• Product Manual
• Configuration Tool
• Product Support Portal

Additional Resources

• SIRIUS System Overview
• Technical Assistance
• Online Training
• Industry Mall
• SIRIUS 3RV2 Motor Starter Protectors