Circuit Breakers

Part Number	Description / PDF	Quantity
2CU5R Altech Corporation	2CU5R 5A MCBCCHAR2P 480Y/277VACU	78
1D5UR Altech Corporation	1D5UR 5A MCB D CHAR 1 P 277VAC U	36
TR11-C-X-63-B-1-C-1.75A Altech Corporation	CIRCUIT BREAK MET NUT 1.75A	1100
GFR2B25100 Altech Corporation	EGFP+OL 25A277V AC 100MA B TRIP	0
2B6UM Altech Corporation	2B6UM 6A CIRCUIT BREAKER B CHAR2	0
2DU60R Altech Corporation	2DU60R60A MCBDCHAR2P 480Y/277VAC	42
3B25UM Altech Corporation	CIRCUIT BREAKER25UM 25A B CHAR3P	0
2CU16R Altech Corporation	2CU16R 16A MCBCCHAR2P 480Y/277VA	0
2B12UR Altech Corporation	2B12UR 12A MCB B CHAR 2 P 480Y/2	0
GFL2D25030S Altech Corporation	MCCB+EGFP 25A120240V AC 30MA D T	0
TR11-D-X-63-BB-2-N-5.0A Altech Corporation	CIRCUIT BREAK WHITE TRIP BAND 50	0
3Z16UM Altech Corporation	3Z16UM 16A CIRCUIT BREAKER Z CHA	0
1G6UM Altech Corporation	1G6UM 6A CIRCUIT BREAKER G CHAR	0
UV12ACR Altech Corporation	CIRCUIT BREAK UNDERVOLT 12VAC	0
3G2.5UM Altech Corporation	3G2.5UM 2.5ACIRCUIT BREAKER G CH	0
DC2DU4L Altech Corporation	DC2DU4L40A MCBDCHAR 2P250VDCUL48	6
1C05DL Altech Corporation	1C05DL 0.5A CIRCUIT BREAKER C CH	48
1C1DL Altech Corporation	1C1DL 1A CIRCUIT BREAKER C CHAR	0
3E1UM Altech Corporation	3E1UM 1A CIRCUIT BREAKER ECHAR3P	0
3G4UM Altech Corporation	3G4UM 4ACIRCUIT BREAKER G CHAR3P	16

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