Mv Vacuum Circuit Breakers

Timetric Mv Vacuum Circuit Breakers  Insulation properties of vacuum

Wenzhou Shuyi Import and Export Co., Ltd. is a professional manufacturer of Timetric Mv Vacuum Circuit Breakers in China and a trusted manufacturer. Vacuum has strong insulation characteristics. In a vacuum circuit breaker, the gas is very thin and the free stroke of gas molecules is relatively large, so the chance of collision is very small. Therefore, collision dissociation is not the main reason for vacuum gap breakdown, but the metal particle precipitated from the electrode under the action of high strength electric field is the main factor causing insulation damage.

The insulation strength in vacuum gap is not only related to the size of gap and the uniformity of electric field, but also greatly affected by the properties of electrode materials and surface conditions. In the case of a small distance gap (2-3 mm), the vacuum gap has higher insulation characteristics than the high pressure air and SF6 gas, which is the reason why the contact distance of the vacuum circuit breaker is generally small.

The effect of electrode materials on the breakdown voltage is mainly manifested in the mechanical strength (tensile strength) and melting point of metal materials. The higher the tensile strength and melting point, the higher the insulation strength of the electrode under vacuum.

The experiment shows that the higher the vacuum degree, the higher the breakdown voltage of the gas gap, but above 10-4 bracket, it basically remains unchanged, so, to maintain the insulation strength of the vacuum arc extinguishing chamber, the vacuum degree should not be less than 10-4 bracket.

Timetric Mv Vacuum Circuit Breakers Parameter (Specification)

Timetric Mv Vacuum Circuit Breakers Use environment

a) Ambient air temperature shall not exceed +40oC, the lower limit; -25oC,
b) The altitude is not more than 2000M
c) humidity; The daily mean value of relative humidity is less than 95% and the monthly mean value is less than 90%. The average daily vapor pressure is not more than 2. 2KPA, monthly mean not greater than 1.8KPA
d) The surrounding air should not be significantly polluted by corrosive or flammable gases and water vapor
e) No regular strenuous exercise
f) When the contactor is running, the dip Angle between the installation plane and the horizontal shall not be greater than 5o
g) Beyond the requirements of the above conditions, the user and the manufacturer shall agree.

Timetric Mv Vacuum Circuit Breakers  Details