Circuit breaker is simply a switch that manually or automatically connect or disconnect the electrical power in a circuit. Switching (open and close situation) is done in order to controlling and protecting the circuit.
Which type of protection:
Protection against excess current caused by overload and short circuit to prevent the damage.
Note1: The different between conventional fuse and circuit breaker is that there is no need to replace the part after the power is cut off and it can be used after solving the problem of circuit.
Let's get acquainted with the classification of circuit breakers based on the type of the Dielectric:
1- Air Circuit Breaker
- Plain / Cross blast ACB
- Airblast ACB
2- Oil Circuit Breaker
- Bulk oil CB
- Minimum oil CB
3- SF6 Circuit Breaker
- Single interrupter SF6 CB
- Two interrupters SF6 CB
- Four interrupters SF6 CB
4- Vacuum Circuit Breaker
Now we classify circuit breakers based on the voltage and current:
1- Low Voltage: Less than 1 kV
Note2: for low voltage normally we use the Air Circuit Breaker types.
Miniature circuit breaker (MCB): up to 125A
1A, 2A, 4A, 6A, 10A, 13A, 16A, 20A, 25A, 32A, 40A, 50A, 63A, 80A, 100A and 125A
Moulded Case Circuit Breaker (MCCB): up to 1600A
2- Medium Voltage: Between 1 kV and 72 kV
Air/Vacuum/SF6 Circuit breakers: up to 6300A
3- High Voltage: 72.5 kV and higher
We can also classify circuit breakers based on the poles:
1- Single Pole (Normally up to 30A), common CB at home.
2- Double Pole (Normally up to 200A), for larger appliance (e.g. dryer, water heater etc.)
3- Three Pole
4- Four Pole
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