| Image | Part Number | Description / PDF | Quantity | Rfq |
|---|---|---|---|---|
 |
Carlo Gavazzi |
MCB UL1077 C 3P 63A |
10 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM 63A 240VAC/125VDC |
24 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 16A 480/277V |
12 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 20A 480/277V |
4 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 50A 240VAC |
2 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 1.6A 480/277V |
4 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 6A 480/277V |
4 |
|
 |
Carlo Gavazzi |
MCB UL1077 C 3P 6A |
5 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 1A 480/277V |
9 |
|
 |
Carlo Gavazzi |
MMS 32A STD BREAK 0.25-0.4A |
5 |
|
 |
Carlo Gavazzi |
MMS 32A STD BREAK 0.1-0.16A |
5 |
|
 |
Carlo Gavazzi |
CIR BRK THRM-MAG 5A 240VAC/60VDC |
23 |
|
 |
Carlo Gavazzi |
MMS 32A HIGH BREAK 0.63-1A |
0 |
|
 |
Carlo Gavazzi |
MCB UL1077 C 1P 4A |
16 |
|
 |
Carlo Gavazzi |
MMS 32A STD BREAK 6-10A |
7 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM 32A 240VAC/125VDC |
11 |
|
 |
Carlo Gavazzi |
CIR BRKR THERM-MAG 6A 240VAC |
4 |
|
 |
Carlo Gavazzi |
CIR BRK THERM-M 35A 240VAC/60VDC |
17 |
|
 |
Carlo Gavazzi |
MCB UL1077 C 2P 25A |
18 |
|
 |
Carlo Gavazzi |
MCB HV UL489 C 1P 30A LUG T |
18 |
|
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.
| 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 |
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
| 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 |
| 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 |
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
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