Circuit Breakers

Part Number	Description / PDF	Quantity
4430.0523 Schurter	CIR BRKR THRM 11A 240VAC 60VDC	18
4430.2863 Schurter	CIR BRKR THRM 15A 240VAC 60VDC	19
3-101-231 Schurter	CIR BRKR THRM 8A 240VAC 48VDC	88
4420.0166 Schurter	CIR BRKR THRM MAG 27A 277V 65V	0
4430.2105 Schurter	CIR BRKR THRM 16A 240VAC 60VDC	0
4411.001 Schurter	CIR BRKR THRM 20A 277VAC 28VDC	26
4430.2309 Schurter	CIR BRKR THRM 15A 240VAC 60VDC	475
4430.1708 Schurter	CIR BRKR THRM 10A 240VAC 60VDC	0
4404.0105 Schurter	CIRC BREAKER PCB MNT 15A	4659300
4411.0214 Schurter	CIR BRKR THRM 3A 277VAC 28VDC	14
4400.0323 Schurter	CIR BRKR THRM 800MA 240VAC 48VDC	0
4411.0007 Schurter	CIR BRKR THRM 15A 277VAC 28VDC	3740
4411.0018 Schurter	CIR BRKR THRM 16A 277VAC 28VDC	16
4435.0384 Schurter	CIR BRKR THRM 240VAC 60VDC	10
4435.0186 Schurter	CIR BRKR THRM 2A 240VAC 60VDC	0
4435.0623 Schurter	CIR BRKR THRM 3A 240VAC 32VDC	0
4435.0302 Schurter	CIR BRKR THRM 16A 240VAC 32VDC	9
4435.0174 Schurter	CIR BRKR THRM 10A 240VAC 32VDC	11
4420.037 Schurter	CIR BRKR THRM MAG 1A 480V 65V	7
4404.0101 Schurter	CIRC BREAKER PCB MNT 8A	105

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