What issues should we pay attention to use snap-in electrolytic capacitors?
Our use method, process and so on will affect the service life of our snap-in electrolytic capacitors, so what issues should we pay attention to?
The conductivity of the snap-in electrolytic capacitors is determined by the ionization ability and viscosity of the electrolyte. When the temperature is lowered, the viscosity of the electrolytic solution is increased, and thus the ion mobility and conductivity are decreased. When the electrolyte is frozen, the ion mobility is so low that it has very high electrical resistance.Contrary, excessive heat will accelerate the evaporation of the electrolytic solution. When the amount of electrolytic solution is reduced to a certain limit, the life of the snap-in electrolytic capacitors is terminated.When working in the cold area (generally below -25 ℃), heating is needed to ensure the normal working temperature of the electrolytic snap-in electrolytic capacitors . Such as outdoor UPS, in Northeast China are equipped with heating plates.
If the horn capacitor runs at a temperature higher than its maximum allowable temperature for a long time, it will accelerate the thermal aging of the snap-in electrolytic capacitors.Therefore, on the one hand, a horn capacitor whose temperature category is compatible with the actual operating environment temperature should be selected. Therefore, in the installation and use of the horn capacitor, special attention should be paid to the ventilation, heat dissipation and radiation problems of the horn capacitor under actual operating conditions, so that the horn capacitor can The heat generated during operation can be dissipated in time, and every effort is made to reduce the temperature of the medium inside the horn capacitor under high temperature conditions.
The snap-in electrolytic capacitors is easy to be broken down in the over-voltage state, and the surge voltage and instantaneous high voltage often occur in practical applications. Tests show that the commonly used 450V / 470uF 105 ℃ imported ordinary 2000 hours electrolytic snap-in electrolytic capacitors is At 1.34 times the rated voltage, the horn capacitor will leak and gas after 2 hours, and the top will be opened. According to statistics and analysis, the failure of PFC output electrolytic horn capacitors in communication switching power supplies close to the power grid is mainly due to power grid surges and high voltage damage. The voltage selection of electrolytic horn capacitors is generally subject to two-level derating, and it is more reasonable to reduce the voltage to 80% of the rated value.