Circuit Breakers

Part Number	Description / PDF	Quantity
1Z03UM Altech Corporation	1Z03UM 0.3A CIRCUIT BREAKER Z CH	0
GFR4B10300 Altech Corporation	EGFP+OL 10A480Y277V AC 300MA B T	0
2D20DL Altech Corporation	2D20DL 20A CIRCUIT BREAKER D CHA	0
GFR2D30100 Altech Corporation	EGFP+OL 30A277V AC 100MA D TRIP	0
GFL2D05100SN Altech Corporation	MCCB+EGFP 5A120240V AC 100MA D T	0
GF240300 Altech Corporation	EGFP 40A277V AC 300MA 1P+N 5060H	0
GFR4C20300 Altech Corporation	EGFP+OL 20A480Y277V AC 300MA C T	0
2DU5R Altech Corporation	2DU5R5A MCBDCHAR2P 480Y/277VACUL	78
GFR4D25300 Altech Corporation	EGFP+OL 25A480Y277V AC 300MA D T	3
3BU63R Altech Corporation	3BU63R63AMCBBCHAR3P 480Y/277VACU	8
GFR2D10030 Altech Corporation	EGFP+OL 10A277V AC 30MA D TRIP 1	0
GFL2B30030S Altech Corporation	MCCB+EGFP 30A120240V AC 30MA B T	6
2E16UM Altech Corporation	2E16UM 16A CIRCUIT BREAKER E CHA	78
3C60UM Altech Corporation	3C60UM 60A CIRCUIT BREAKER C CHA	8
3CU20R Altech Corporation	3CU20R20AMCBCCHAR3P 480Y/277VACU	4
2D12DL Altech Corporation	2D12DL 12A CIRCUIT BREAKER D CHA	0
1BU1R Altech Corporation	1BU1R 1A MCB B CHAR 1P277VACUL10	12
2G10UM Altech Corporation	2G10UM 10A CIRCUIT BREAKER G CHA	6
GFR4C12030 Altech Corporation	EGFP+OL 12A480Y277V AC 30MA C TR	0
1C03UL Altech Corporation	1C03UL 0.3A CIRCUIT BREAKER C CH	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