4 pole 50 amp miniature circuit breaker (MCB) operates at a rated frequency of 50-60Hz, which is commonly used in electrical systems to protect circuits from overcurrent, short circuits, and overload conditions, ensuring reliable performance and safety.
4 Pole MCB Breaker Features
- Rapid arc extinguishing system: This 4P mini circuit breaker eliminates line danger, can sense even small currents, and provides sensitive protection.
- Thermosetting shell: 4 pole MCB breaker uses thermosetting plastic, which solidifies or has insoluble characteristics under heat or other conditions.
- Sealed terminal: 50 amp miniature circuit breaker has a built-in sealed terminal, which is rust-proof and convenient, and meets certification standards.
- Ergonomic handle: The handle is comfortable to operate, has high segmentation capacity, and is sensitive to action.
Technical Data
Model |
ATO-BY6-63-4P-50A |
Number of Poles |
4P |
Rated Frequency |
50-60Hz |
Frame Grade Current |
63A |
Rated Current(In) |
50A |
Rated Insulation Voltage |
400V |
Rated Impulse Withstand Voltage (Uimp) |
4000KV |
Rated Short-circuit Capacity(Inc) |
3000-6000KA |
Producible Leakage Protection Type |
AC type |
Electrical Characteristics |
Short Circuit Protection, Overload Protection, Power Failure Protection |
Electrical Life |
10000 |
Mechanical Life |
10000 |
Protection Level |
IP20 |
Comply with the Standard |
GB/T10963.1-2020 IEC60898-1 |
4 Pole MCB Breaker Dimensions (Unit: mm)

4 Pole MCB Breaker Wiring

How to Choose a Miniature Circuit Breaker for Home?
Rated Current |
Copper Core Wire |
Load Power |
Applications |
1~5A |
<1mm |
≤1100W |
Low-power Equipment |
6A |
≥1mm |
≤1320W |
Lighting |
10A |
≥1.5mm |
≤2200W |
Lighting |
16A |
≥2.5mm |
≤3520W |
Lighting, Sockets, 1~1.5 hp Air Conditioner |
20A |
≥2.5mm |
≤4400W |
Lighting, Sockets, 1~1.5 hp Air Conditioner |
25A |
≥4mm |
≤5500W |
Lighting, Sockets, 1~2.5 hp Air Conditioner |
32A |
≥6mm |
≤7040W |
Sockets, 3 hp Air Conditioner, 6 kW Water Heater |
40A |
≥10mm |
≤8800W |
8 kW Instant Water Heater, Main Power Switch |
50A |
≥10mm |
≤11000W |
Main Power Switch |
63A |
≥16mm |
≤13200W |
Main Power Switch |
Tips: How do miniature circuit breakers protect circuits?
Miniature circuit breakers (MCBs) protect electrical circuits by automatically interrupting the current flow when an overload or short circuit occurs. They use two primary mechanisms: a thermal trip and a magnetic trip.
The thermal trip responds to prolonged overloads. Inside the mini circuit breaker, a bimetallic strip heats up as the current increases. If the current exceeds a safe limit for an extended period, the strip bends and triggers the trip mechanism, disconnecting the circuit to prevent overheating and potential fire hazards.
The magnetic trip reacts to sudden surges, like those from short circuits. It uses an electromagnet that generates a magnetic field proportional to the current. If the current spikes abruptly, the magnetic force pulls a lever to trip the breaker instantly, stopping the flow to prevent equipment damage.
MCBs are resettable and provide reliable, quick protection, making them essential for safeguarding electrical systems in homes, industries, and commercial buildings.