Circuit Breakers

Image Part Number Description / PDF Quantity Rfq
2907202

2907202

Phoenix Contact

CIR BRKR MAGHYDR 3A 120VAC/50VDC

1

2907569

2907569

Phoenix Contact

CIR BRKR 13A 277VAC 60VDC

580

2800854

2800854

Phoenix Contact

CIR BRKR 10A 277VAC 50VDC

1469

0916609

0916609

Phoenix Contact

CIR BRKR THRMMAG 8A 240VAC 28VDC

4228

0903046

0903046

Phoenix Contact

CIR BRKR SOLID STATE 6A 24VDC

5

0914743

0914743

Phoenix Contact

CIR BRKR 300MA 250VAC 65VDC

0

2907595

2907595

Phoenix Contact

CIR BRKR 16A 480VAC 125VDC

0

2800894

2800894

Phoenix Contact

CIR BRKR THRMMAG 4A 277VAC 80VDC

4

2907609

2907609

Phoenix Contact

CIR BRKR 3A 480VAC 125VDC

9

2907597

2907597

Phoenix Contact

CIR BRKR 20A 480VAC 125VDC

106

1020057

1020057

Phoenix Contact

CIRCUIT BRAKER 50A

850

1020091

1020091

Phoenix Contact

CIRCUIT BRAKER 10A

82

1019975

1019975

Phoenix Contact

CIRCUIT BREAKER 4A

0

0902182

0902182

Phoenix Contact

CIR BRKR THRMMAG 2A 277VAC LEVER

6

1019989

1019989

Phoenix Contact

CIRCUIT BRAKER 40A

20

1020019

1020019

Phoenix Contact

CIRCUIT BRAKER 5A

21131

0914099

0914099

Phoenix Contact

CIR BRKR THRMMAG 2A 250VAC 65VDC

166

2800860

2800860

Phoenix Contact

CIR BRKR THRMMAG 3A 277VAC 50VDC

36

0903023

0903023

Phoenix Contact

CIR BRKR SOLID STATE 1A 24VDC

22205

2800898

2800898

Phoenix Contact

CIR BRKR 10A 277VAC 80VDC

0

Circuit Breakers

1. Overview

Circuit breakers are automatic electrical switches designed to protect circuits from damage caused by overloads or short circuits. Unlike fuses, they can be reset after tripping. Modern circuit breakers ensure electrical safety, prevent equipment damage, and maintain system reliability in residential, commercial, and industrial applications.

2. Main Types and Functional Classification

TypeFunction FeaturesApplication Examples
MCB (Miniature Circuit Breaker)Thermal-magnetic protection, <100A ratingResidential wiring, lighting circuits
MCCB (Molded Case Circuit Breaker)Adjustable trip settings, 10-2500A ratingIndustrial machinery, HVAC systems
ACB (Air Circuit Breaker)High fault current interruption, 400-6300A ratingPower distribution in data centers
RCCB (Residual Current Circuit Breaker)Earth leakage protection (5-500mA sensitivity)Outdoor outlets, swimming pool equipment
RCBO (Residual Current Breaker with Overcurrent)Combines overload, short-circuit, and leakage protectionHospital equipment, construction sites

3. Structure and Components

Typical components include: - Enclosure: Flame-retardant insulating material housing - Contacts: Silver alloy for high conductivity - Trip Mechanism: Bimetallic strip (thermal) and electromagnetic coil (magnetic) - Arc Extinguisher: Multi-plate chamber for arc suppression - Operating Lever: Manual ON/OFF control with position indicators

4. Key Technical Parameters

ParameterDescriptionImportance
Rated Current (In)Maximum continuous current without trippingDetermines load capacity
Rated Voltage (Un)Maximum operating voltageEnsures insulation safety
Breaking Capacity (Icu)Maximum fault current interrupting capabilityPrevents catastrophic failure
Tripping CharacteristicsTime-current curve (B/C/D types)Matches load requirements
Pole Number1P to 4P configurationsDetermines phase protection

5. Application Fields

  • Power distribution: Residential panels, commercial switchboards
  • Industrial equipment: Motors, transformers, CNC machines
  • Renewable energy: Solar inverters, wind turbine systems
  • Transportation: EV charging stations, rail traction systems

6. Leading Manufacturers and Products

ManufacturerRepresentative ProductKey Features
Schneider ElectricActi 9 seriesModular design, 0.5-125A range
Siemens5SJ seriesHigh short-circuit withstand, DIN rail mount
ABBEmax seriesSmart connectivity, up to 6300A
General ElectricTHQL seriesUL-certified, industrial motor protection

7. Selection Guidelines

Key considerations: - Match rated current to load requirements (125% safety margin) - Select tripping curve (Type B for resistive loads, C for motors) - Verify breaking capacity against system fault levels - Consider environmental factors (temperature, altitude) - Ensure compliance with standards (IEC 60898, UL 489) - Example: For a 20kW motor (400V), select MCCB with 63A rating, Type C curve, 50kA breaking capacity

8. Industry Trends

Emerging trends include: - Smart grid integration with IoT-enabled monitoring - Compact designs for space-constrained applications - Eco-friendly materials with halogen-free construction - Integration with renewable energy systems - Predictive maintenance via AI-powered diagnostics - Increased adoption of DC circuit breakers for EV infrastructure

RFQ BOM Call Skype Email
Top