Circuit Breakers

Part Number	Description / PDF	Quantity
2CU05R Altech Corporation	2CU05R0.5A MCBCCHAR2P 480Y/277VA	0
GFR4D12030 Altech Corporation	EGFP+OL 12A480Y277V AC 30MA D TR	0
2G125UM Altech Corporation	2G125UM 12.5ACIRCUIT BREAKER G C	0
UV24DCL Altech Corporation	CIRCUIT BREAK UNDERVOLT 24V DC C	0
1C15UR Altech Corporation	1C15UR 15A MCB C CHAR 1 P 277VAC	0
3DU3R Altech Corporation	3DU3R 3AMCBDCHAR3P 480Y/277VACUL	80
GFL2D12300S Altech Corporation	MCCB+EGFP 12A120240V AC 300MA D	0
3CU3L Altech Corporation	3CU3L3.0AMCBCCHAR3P 480Y/277VACU	120
2BU10R Altech Corporation	2BU10R 10A MCBBCHAR2P 480Y/277VA	12
GFL2D100102 Altech Corporation	MCCB+EGFP 10A240V AC 10MA D TRIP	0
GFR2B16100 Altech Corporation	EGFP+OL 16A277V AC 100MA B TRIP	0
2B5UM Altech Corporation	2B5UM 5A CIRCUIT BREAKER B CHAR2	12
GFR2D15300 Altech Corporation	EGFP+OL 15A277V AC 300MA D TRIP	0
GFL2D25300SN Altech Corporation	MCCB+EGFP 25A120240V AC 300MA D	0
2Z5UM Altech Corporation	2Z5UM 5A CIRCUIT BREAKER Z CHAR2	0
GFR2C08010 Altech Corporation	EGFP+OL 8A277V AC 10MA C TRIP 1P	0
3BU1R Altech Corporation	3BU1R1AMCBBCHAR3P 480Y/277VACUL1	0
2B16UR Altech Corporation	2B16UR 16A MCB B CHAR 2 P 480Y/2	60
GFL2D32100S Altech Corporation	MCCB+EGFP 32A120240V AC 100MA D	0
1DU13L Altech Corporation	1DU13L 13A MCB D CHAR 1P277VACUL	24

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