MCBs are used to perform many functions such as local control switches, isolating switches against faults and overload protection devices for installations or specific equipments or appliances.
Circuit Breaker Information
- Rated Current: 50 amp
- Rated Voltage: 230/400V AC, 50Hz
- Number of poles: 3 pole
- 6 kA short circuit breaking capacity
- Standard 35 mm DIN rail mounting
- Thermal-magnetic over current protection
Technical Data
Model | CHN-NB8-633PC50 |
Electrical Parameters | Height | 86 mm |
Width | 18 mm per pole |
Mounting | DIN Rail |
Rated Current (In) | 50A |
Number of poles | 3P |
Rated Voltage (Ue) | 230/400V |
Rated Insulation Voltage (Ui) | 500V |
Dielectric Test Voltage | 2000V |
Reted Frequency | 50Hz |
Short Circuit Interrupting Capacity | 6KA |
Trip Characteristic | C Curve (5-10In) |
Rated Short-Circuit Breaking Capacity | 6000A |
Operating Short-Circuit Breaking Capacity | 6000A |
Mechanical Parameters | Electrical Life | 10000 times |
Mechanical Life | 20000 times |
Flame Retardant Grade | V0 |
Protection Degree | Direct installation: IP20B Installed in the distribution box: IP40B |
Calibration Temperature | 30℃ |
Operating Temperature | -35℃~+70℃ |
Storage Temperature | -35℃~+85℃ |
Tightening Torque | 2 N.m |
Max. Tolerable Torque | 2.5 N.m |
Terminal Size Acceptability–Min/Max | 1 mm2 / 25mm2 |
Wire Insertion Depth | 13mm |
Circuit Breaker Dimension (Unit: mm)

Tips: How to select a miniature circuit breaker?
1. Grid frequency
The usable range of alternating current frequency is generally from 50 Hz to 60 Hz for a miniature circuit breaker.
2. Rated current and rated voltage
1) Rated current: The rated current of miniature circuit breaker mainly depends on the working current of protected load. The rated current of the miniature circuit breaker should be larger than the calculated load current of line within 125A. The rated current of miniature circuit breaker has different specifications including 6 A, 10 A, 16 A, 20 A, 40 A and 63A etc. There are several rated current values for over-current tripper under the same level of rating current. Therefore, the rated current of over-current tripper should approach to the actual current of electricity as possible as it could.
2) Rated voltage: The rated working voltage of miniature circuit breaker should be larger than the rated voltage of line within 440V.
3. Short circuit capacity
Short circuit current that occurs between phase lines or between phase line and neutral line is very large, so it is required to have a certain short circuit breaking capacity, for example the rated short circuit breaking capacity of switch is equal to or less than the largest short circuit current that could occur. Because switch is not capable of arc blowout, the excessively high temperature caused by arcing makes contact point short-circuited, destroying distribution lines and equipment. Therefore, the maximum short circuit capacity should be taken full consideration into selecting miniature circuit breaker, and the rated short circuit capacity should be larger than the maximum short circuit current that could occur in line.
Miniature circuit breaker with 3-pole, 50 ampere current rating, excellent breaking capability of 6kA at 240/415V AC voltage, module width of only 18 mm per pole. C curve trip characteristic, can be used in IEC standard applications.