Circuit Breakers

Part Number	Description / PDF	Quantity
1020074 Phoenix Contact	CIRCUIT BRAKER 20A	27
0912050 Phoenix Contact	CIR BRKR 10A 24VDC AUTO RESET	0
2907663 Phoenix Contact	CIR BRKR 16A 480VAC 125VDC	4
1019995 Phoenix Contact	CIRCUIT BREAKER 2A	44
2907611 Phoenix Contact	CIR BRKR 5A 480VAC 125VDC	1394
2800864 Phoenix Contact	CIR BRKR THRMMAG 8A 277VAC 50VDC	0
1020058 Phoenix Contact	CIRCUIT BRAKER 60A	3021
0912020 Phoenix Contact	CIR BRKR SOLID STATE 10A 24VDC	2
1019910 Phoenix Contact	CIRCUIT BREAKER 3A	82
2907534 Phoenix Contact	CIR BRKR 40A 240VAC 125VDC	78
1020039 Phoenix Contact	CIRCUIT BREAKER 3A	3
0903032 Phoenix Contact	CIR BRKR SOLID STATE 1A 24VDC	3
2800908 Phoenix Contact	CIR BRKR SOLID STATE 1A 24VDC	18
2907199 Phoenix Contact	CIR BRKR MAG-HYDR 20A 50VDC	820
2800917 Phoenix Contact	CIR BRKR SOLID STATE 3A 24VDC	342
2800870 Phoenix Contact	CIR BRKR THRMMAG 2A 277VAC 80VDC	11
2907641 Phoenix Contact	CIR BRKR 25A 277VAC 60VDC	11139
1020028 Phoenix Contact	CIRCUIT BRAKER 20A	1968
0914167 Phoenix Contact	CIR BRKR 10A 250VAC 65VDC	329
2907535 Phoenix Contact	CIR BRKR 50A 240VAC 125VDC	27

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

Type	Function Features	Application Examples
MCB (Miniature Circuit Breaker)	Thermal-magnetic protection, <100A rating	Residential wiring, lighting circuits
MCCB (Molded Case Circuit Breaker)	Adjustable trip settings, 10-2500A rating	Industrial machinery, HVAC systems
ACB (Air Circuit Breaker)	High fault current interruption, 400-6300A rating	Power 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 protection	Hospital 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

Parameter	Description	Importance
Rated Current (In)	Maximum continuous current without tripping	Determines load capacity
Rated Voltage (Un)	Maximum operating voltage	Ensures insulation safety
Breaking Capacity (Icu)	Maximum fault current interrupting capability	Prevents catastrophic failure
Tripping Characteristics	Time-current curve (B/C/D types)	Matches load requirements
Pole Number	1P to 4P configurations	Determines 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

Manufacturer	Representative Product	Key Features
Schneider Electric	Acti 9 series	Modular design, 0.5-125A range
Siemens	5SJ series	High short-circuit withstand, DIN rail mount
ABB	Emax series	Smart connectivity, up to 6300A
General Electric	THQL series	UL-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