Circuit Breakers

Part Number	Description / PDF	Quantity
DC2CU3L Altech Corporation	DC2CU3L30A MCB CCHAR 2P 250VDC U	0
MS2.5 Altech Corporation	MS25 MANUAL MOTOR CONTROLLER 16-	3
GFR2C40100 Altech Corporation	EGFP+OL 40A277V AC 100MA C TRIP	0
3C2.5UM Altech Corporation	3C2.5UM 2.5A CIRCUIT BREAKER C C	0
2D50UM Altech Corporation	2D50UM 50A CIRCUIT BREAKER D CHA	0
1B1.6UM Altech Corporation	1B1.6UM 1.6A CIRCUIT BREAKER B C	0
GFL2B40300S Altech Corporation	MCCB+EGFP 40A120240V AC 300MA B	0
1E20UM Altech Corporation	1E20UM 20A CIRCUIT BREAKER E CHA	60
3D4UM Altech Corporation	3D4UM 4A CIRCUIT BREAKER D CHAR3	24
1ZU40L Altech Corporation	1ZU40L40A MCB Z CHAR 1P277VACUL4	12
GFR4C32300 Altech Corporation	EGFP+OL 32A480Y277V AC 300MA C T	0
3G125UM Altech Corporation	3G125UM 12.5ACIRCUIT BREAKER G C	0
GFL2C20010SN Altech Corporation	MCCB+EGFP 20A120240V AC 10MA C T	0
GFL2D080302 Altech Corporation	MCCB+EGFP 8A240V AC 30MA D TRIP	0
GFL2C053002 Altech Corporation	MCCB+EGFP 5A240V AC 300MA C TRIP	0
1CU30R Altech Corporation	1CU30R 30A MCB C CHAR 1P277VACUL	0
1B16UR Altech Corporation	1B16UR 16A MCB B CHAR 1 P 277VAC	0
2C32UL Altech Corporation	2C32UL 32A CIRCUIT BREAKER C CHA	6
2B15UR Altech Corporation	2B15UR 15A MCB B CHAR 2 P 480Y/2	18
3C1.6UM Altech Corporation	3C1.6UM 1.6ACIRCUIT 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