Guidelines For Using
Upon using aluminum electrolytic capacitors, please proper handling and observing to following important points will insure optimum capacitor, performance and long life.
1.Polarization
Aluminum electrolytic capacitor has polarity ,the polarity is marked on the body of the capacitor, if the capacitor is used in reverse polarity, the circuit may become a short circuit and the capacitor may be damaged by the safety vent operation etc. when the polarity in a circuit sometimes reversed or unknown, a bi-polar capacitor should be used, however the DC capacitor must not be used for AC voltage application.
2.Applying Voltage
Do not apply voltage exceeding the rated voltage of the capacitor. The capacitor may be damaged or the capacitor's life may be shortened as the leakage current increases . When AC voltage is superimposed to Dc voltage, the sum of the peak AC and DC voltage should not exceed the rated voltage or the reverse voltage of the capacitor. Recommended working voltage is 70 to 80 percent of rated voltage using capacitors at recommended working voltage prolongs capacitor life.
3.Ripple Current
Maximum permissible ripple current is specified in individual specifications.Please do not apply excessive ripple current, which will shorten life expectancy due to heat rise and internal gas evaporation. Aluminum electrolytic capacitors with high ripple current capability are available upon request.
4.Operating Temperature
The characteristic of capacitors change with the operating temperature. The capacitance and leakage current in crease but tang decrease at higher temperatures. The capacitance and leakage current decrease and buttang increase at lower temperature. Use the electrolytic capacitors according to the specified operating temperature range. Usage at room temperature will ensure longer life.
5.Charge and Discharge
In the circuit subjected to rapid charge and discharge cycles ,capacitors may be damaged, it's life may be shortened by capacitance decrease or heat rise ect. Be sure to use special capacitors in these applications.
6.Voltage Treatment
Long periods of storage have no effect to capacitor's capacitance and tang ,however such periods tend to increase leakage current and decrease with stangd voltage. If the rated voltage is applied to such a product, a large leakage current occurs and the generates internal heat, which may damaged the capacitor. If the electrolytic capacitor is allowed to stand for a long time, therefore, use it after giving voltage treatment.
7.Soldering
When soldering a printed circuit board with various components, care must be taken that the soldering temperature is not too high or the dipping time is not too long. Otherwise, there will be adverse effects on the electrical characteristic and insulation sleeve of electrolytic capacitors. When the capacitor dipped in solder bath recommendable with in 260℃ and 10seconds to avoid damage of capacitor unit.
8.Insulation
a.Aluminum electrolytic capacitors are ordinarily covered with plastic sleeve to mark.
b.If the soldering iron comes in contact with the electrolytic capactrolytic body during wiring,damage to the plastic sleeve and/or case may result in defective insulation, or improper protection or the capacitor element.
c.please mount the capacitor on PC board, so that there is no conductive circuit pattern under the mounted capacitor.
9.Exteral Stress
Excessive force or stress to terminals or lead wires of capacitors should be prevented. The stresses like pull, push, bend, etc ., will cause high leakage current, leakage of electrolyte and open/short circuit in worst case.
10.Cleaning
Cleaning circuit boards to remove flux or other extraneous matter. To ensure protection for sleeve marking and sealing materials on capacitor body, capacitor should never be washed or cleaned by halogenous or solvents such as trichloroethene xylene or acetone, etc. Recommended cleaning solvents:Methanol,isopropanol, ethanol, isobutanol, petroleum etner, propyl alcohol and /or commonly detergents.
11.Storage
If electrolytic capacitors are exposed to high temperatures and direct sun light, the life of the capacitor may be adversely affected. Storage in a high humidity atmosphere may affect the solderability of lead wires and terminals. If capacitors are stored at the low temperature and low humidity , they will have longer storage time.