Precautions for Using Film Capacitors

Precautions for Using Film Capacitors

Based on years of work experience, JYH HSU (JEC) engineers remind everyone to pay attention to these main matters when using metallized polypropylene film capacitors (CBB21/CBB22).

1. Working Voltage

The selection of film capacitors depends on the applied high voltage and is affected by factors such as the applied voltage and voltage waveform, frequency, and ambient temperature. Before use, please check whether the superimposed voltage across the capacitor is within the rated value, and do not exceed the upper voltage limit of the capacitor at any time.

2. Working Current

Due to the loss of the capacitor, when used under high-frequency or high-pulse conditions, the pulse or AC passing through the capacitor will cause the capacitor itself to heat up and have a temperature rise, and there will be a risk of thermal breakdown (smoke, fire). Therefore, the use conditions of capacitors are not only limited by the rated voltage, but also limited by the rated current.

3. Discharge and Charge

Since the charging and discharging of a capacitor depends on the product of the capacitance and the rate of voltage change, even for low-voltage charging and discharging, excessive capacitance or too fast a rate of voltage change will also cause damage to the capacitor. Therefore, when multiple film capacitors are connected in parallel for voltage testing or life testing, please connect an appropriate current limiting resistor in series with each capacitor.

4. Flame Retardancy

Although a fire-resistant flame-retardant material --- flame-retardant epoxy resin or plastic case is used in the outer packaging of the film capacitor, the external continuous high temperature or flame can still deform the capacitor core and cause the outer packaging to rupture, causing the capacitor core to be damaged, melt or burnt.

5. Capacitors for Suppressing Electromagnetic Interference in Power Supplies

When a capacitor is used in the power line to suppress interference, not only the normal voltage, but also an abnormal pulse voltage occurs, which may cause the capacitor to emit smoke or catch fire. Therefore, the standards of cross-line capacitors are strictly regulated in different countries. Please use certified safety capacitors. It is not recommended to use DC capacitors in jumper circuits.

Select a reliable manufacturer when purchasing electronic components can avoid a lot of unnecessary trouble. JYH HSU(JEC) (or Dongguan Zhixu Electronics) not only has full models of ceramic capacitors with guaranteed quality, but also offers worry-free after-sales. JEC factories are ISO 9000 and ISO 14000 certified. Welcome to contact us: https://www.jeccapacitor.com