Function of miniature circuit breaker
The RB12-63 series miniature circuit breaker operates in a 50Hz AC circuit. With a rated voltage of 230/400V, it caters to a maximum current of 63A. Its main function of mcb circuit breaker is to offer protection against overloads and short circuits. Normally, it acts as a seldom-switched element. However, it also serves as an isolator, disconnecting the circuit for equipment or circuit maintenance.
The miniature circuit breaker can use in industrial and commercial buildings and residential homes. Adherence to the IEC/EN 60898-1 standard is maintained throughout its design and operation.
Main Parameters of miniature circuit breaker (Form 1)
| Types | Values |
| Rated voltage Un | 240V/415V AC(1P),415V AC(2P、3P、4P) |
| Rated current In | 1A,2A,3A,4A,6A,10A,16A,20A,25A,32A,40A,50A,63A |
| Poles | 1P、2P、3P、4P |
| lnstant tripping type | B,C,D |
| Rated short circuit breaking capacity(lcn) | 10000A |
| Overcurrent protection properties | See Form 2，Diagram 1,2 and 3 |
| Mechanical and electrical life | See Form 3 |
| Connection wire | See Form 4 |
| Tightening torque | 2.5N.m |
| Nominal temperature °C | 30°C |
| Operated ambient temperature °C | -5~+40°C |
| Stored ambient temperature °C | -25~+70°C |
| Pollution level | 2 |
| Protection level | IP20 |
| Mounting type | ll |
Different types of mcb overcurrent protection properties(Nominal temperature 30 °C) (Form 2)
| ltem | Type | Test current |
Initial status | Tripping or non tripping time limit |
Expected result | Remarks |
| a | BCD | 1.13In | Cold | t≤1h | Non tripping | |
| b | 1.45In | est following the previous procedure; Process after test |
t<1h | Trip | Current increases to stipulated value within 5s |
|
| c | 2.55In | Cold | 1s<t<60s (for In≤32A) 1s<t<120s (for In>32A) |
Trip | ||
| d | BCD | 3In 5In 10ln |
Cold | t≤0.1s | Non tripping | Connection of current by opening auxiliary switch |
| e | BCD | 5In 10ln 20In |
Cold | t≤0.1s | Trip | Connection of current by opening auxiliary switch |
Diagram 1,2 and 3
Mechanical and electrical lifeﾠ (Form 3)
|
Type
|
Times
|
|
Electrical life
|
10000
|
|
Mechanical life
|
20000
|
Connection Wire of miniature circuit breaker (Form 4)
| Rated current In(A) | Copper wire nominal cross-sectional area S(mm2) |
| 1~6 | 1.0 |
| 10 | 1.5 |
| 16,20 | 2.5 |
| 25 | 4 |
| 32 | 6 |
| 40,50 | 10 |
| 63 | 16 |
Overall and mounting sizes (mm)
