Applications and functions
VA51 series air circuit breaker is applied to distribute electrical energy and protecte circuit and power supply equipments in AC power distribution network with 50 Hz, rated voltage up to 660 V (690 V) and rated current from 630 A to 6300 A to prevent it from overload, under voltage, short circuit, single phase rounding hazards and other faults.
The circuit breaker has intelligent protecting functions, and the selective protection accuracy, which can improve the reliability of power supply and avoid unnecessary power faults. it has an open communication interface for “four remote patterns” to meet the requirements of control centers and automation systems.
The circuit breaker has a pulse withstand voltage of 8000 V at an altitude of 2000 meters (it will be modified according to the different altitudes, and the maximum is no more than 12000 V).
The circuit breaker can be used as an isolator without an intelligent controller and sensor.
The circuit breaker complies with standard IEC 60947-2, Lowvoltage switchgear and controlgear-Part 2: Circuit-breakers.
Instruction of classification
a. Fixed type
b. Withdrawable type
Number of poles: 3P, 4P
Manual operation (for text and maintenance)
electronic trip unit undervoltage release shunt release
Normal working and installation conditions
Ambient air temperature
The upper limit does not higher than +40 °C, the lower limit is not lower than -5 °C, and the average temperature of 24 h does not higher than +35 °C.
Note: For working conditions where the upper limit exceeds +40 °C or the lower limit is lower than -10 °C or -25 °C, the user should inform us and the altitude of the installation site should not exceed 2000 m.
The relative humidity of the atmosphere is no more than 50% when the ambient air is +40 °C. It can have a higher relative humidity at a lower temperature. The maximum relative humidity of the wettest month is 90%, and the average minimum temperature of the month is 20 °C, in the meanwhile we should also consider the condensation on the surface of the product due to temperature changes. The requirements’ exceeding shall be negotiated with the manufacturer.
Degree of Protection: IP30
Pollution level: 3
Use category: B
Circuit breakers with rated operating voltages equal to or below 660 V (690 V) and under-voltage release and primary coils for power transformers shall be applied to the installation category IV
The auxiliary circuit and control circuit installation category shall be III.
The circuit breaker shall be installed in accordance with the requirements of this manual. The vertical inclination of the circuit breaker shall not exceed 5 degrees (the mining circuit breaker shall not exceed 15 degrees)
Technical data for circuit breakers