Circuit Breakers

Image	Part Number	Description / PDF	Quantity	Rfq
	0914989 Phoenix Contact	CIR BRKR 1.5A 250VAC 65VDC	0
	5043941 Phoenix Contact	CB TMC 1 F1 200 0.1A	0
	2905808 Phoenix Contact	CIRCUIT BREAKER	0
	0914248 Phoenix Contact	CB TMC 1 F1 200 0.8A	0
	0915357 Phoenix Contact	CIR BRKR THRM-MAG 2A LEVER	0
	2905799 Phoenix Contact	CIRCUIT BREAKER	0
	5652256 Phoenix Contact	CIR BRKR	0
	0915412 Phoenix Contact	CIR BRKR THRM-MAG 8A LEVER	0
	0914206 Phoenix Contact	CB TMC 1 F1 200 0.3A	0
	0915784 Phoenix Contact	CIR BRKR THRMMAG 3A 250VAC 65VDC	0
	0915475 Phoenix Contact	CIRCUIT BREAKER THRM-MAG 100MA	0
	0902328 Phoenix Contact	CIR BRKR THRMMAG 1A 480VAC LEVER	0
	0914728 Phoenix Contact	CIR BRKR THRM-MAG 15A 250VAC	0
	0915522 Phoenix Contact	CIR BRKR 400MA 250VAC 65VDC	0
	2905801 Phoenix Contact	CIRCUIT BREAKER	0
	0915687 Phoenix Contact	CIR BRKR 200MA 250VAC 65VDC	0
	0915438 Phoenix Contact	CIR BRKR 12A 250VAC 65VDC	0
	0915823 Phoenix Contact	CIR BRKR THRMMAG 8A 250VAC 65VDC	0
	0911047 Phoenix Contact	ECP 3	0
	0902386 Phoenix Contact	CIR BRKR THRM-MAG 13A 480VAC	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

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