Circuit Breakers

Part Number	Description / PDF	Quantity
GSB633PC4 Carlo Gavazzi	MCB UL1077 C 3P 4A	2
MOCB2-PL3-10A OptiFuse	FUSE FOOTPRINT CB-TYPE II , 10A	380
GMB631PC50 Carlo Gavazzi	CIR BRK THERM-M 50A 240VAC/60VDC	11
4120-G111-K1M1-A1S0ZN-15A E-T-A	CIR BRKR THRM 15A 115VAC 28VDC	0
2800854 Phoenix Contact	CIR BRKR 10A 277VAC 50VDC	1469
2CU20L Altech Corporation	CIR BRKR THRM-MAG 20A LEVER	126
19M-P10-B-175-02 MP	CIR BRKR THRM 175A IP69K	9
4230-T110-K0CE-13A E-T-A	CIR BRK THERM-M 13A 277VAC/60VDC	0
0916609 Phoenix Contact	CIR BRKR THRMMAG 8A 240VAC 28VDC	4228
4230-T120-K0CU-20A E-T-A	CIR BRKR THERM 20A 480VAC/125VDC	3
1610-92-5A E-T-A	CIRCUIT BREAKER THRM 5A 12VDC	3095
IULK1-1REC4-53-5.00-01 Sensata Technologies – Airpax	CIR BRKR MAG-HYDR 5A LEVER	0
MOCB-24-H-20A OptiFuse	HOR. BRACKET-TYPE II MOD,20A 24V	282
106-M2-P10-10A E-T-A	CIR BRKR THRM 10A 250VAC 48VDC	73
R185-100A NTE Electronics, Inc.	CIRCUIT BREAKER,THERMAL 100A	43
T26-2-7.00A-01-11 Sensata Technologies – Airpax	CIR BRKR MAG-HYDR 7A TOGGLE	0
IULK1-1-53-2.50-01 Sensata Technologies – Airpax	CIR BRKR MAG-HYDR 2.5A LEVER	0
203-2-1-63-502-B-1-1 Sensata Technologies – Airpax	TYPE 203 AUX PROTECT	554
9911200005 Weidmuller	CIR BRKR THRMMAG 2A 480VAC 65VDC	526
1278950000 Weidmuller	CIR BRKR THRM 1A 250VAC 65VDC	1755

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