First, the definition of capacitors
Capacitors, as its name suggests, is' equipment, containers', is a charge to accommodate the device. English name: capacitor. Some commonly used capacitors as shown. With the letter C said. Capacitance is large-scale use of electronic equipment in one of the electronic components, widely used in every other straight, coupling, bypass, filtering, tuning circuits, energy conversion and control circuits, and so on.
Second, the main parameters of capacitors
1, a nominal power capacity and allow deviation
Nominal power capacity in the capacitor is marked on the capacitor.
Capacitor is the basic unit of Farah (F), however, this unit too, marked in the field rarely used.
Other units relations are as follows:
1F = 1000mF
1mF = 1000 μ F
1μ F = 1000nF
1n = 1000pF
Capacitors with a nominal capacity of the actual power capacity, said the deviation error, allowing the deviation of the accuracy of that.
Accuracy class and allow the relationship between error: 00 (01) - ± 1%, 0 (02) - ± 2%, Ⅰ - ± 5%, Ⅱ - ± 10%, Ⅲ - ± 20%, Ⅳ - (+20% -10%), Ⅴ - (+50% -20%), Ⅵ - (+50% -30%)
General capacitors used Ⅰ, Ⅱ, Ⅲ level, electrolytic capacitor used Ⅳ, Ⅴ, Ⅵ level, according to use select.
2, rated voltage
At the lowest temperature and the ambient temperature can be rated for the highest increase in the capacitor voltage DC RMS, the general direct mark on the shell in the capacitor, if the voltage capacitor over the pressure, capacitors breakdown, causing permanent damage to be repaired.
3, insulation resistance
DC voltage increase in capacitance, and a current leakage, both known as the ratio of insulation resistance.
When the smaller capacitor, the capacitor depends primarily on the surface, and capacity> 0.1 uf, the main medium depends on the performance, the smaller the better the insulation resistance.
Capacitance of the time constant: to appropriate assessment of large-capacity capacitors in the insulation and the introduction of a time constant, the equivalent capacitance insulation resistance and capacity of the product.
4, loss
Capacitance in the electric field, in units of time due to fever called by the consumption of energy loss. Various provisions of the capacitor are in a frequency range of allowable loss, the loss mainly by the capacitor dielectric loss, conductivity and capacitance loss of all metal parts caused by the resistance.
The role of the DC market, the loss to the capacitor leakage in the form of derivative losses, the general smaller, in the role of alternating electric field, the capacitance of the leakage and loss is not only derivative, but also the polarization and the establishment of the cyclical process.
5, the frequency of
With the increased frequency and capacity of electric capacitors general decline in the present law.
Capacitors, as its name suggests, is' equipment, containers', is a charge to accommodate the device. English name: capacitor. Some commonly used capacitors as shown. With the letter C said. Capacitance is large-scale use of electronic equipment in one of the electronic components, widely used in every other straight, coupling, bypass, filtering, tuning circuits, energy conversion and control circuits, and so on.
Second, the main parameters of capacitors
1, a nominal power capacity and allow deviation
Nominal power capacity in the capacitor is marked on the capacitor.
Capacitor is the basic unit of Farah (F), however, this unit too, marked in the field rarely used.
Other units relations are as follows:
1F = 1000mF
1mF = 1000 μ F
1μ F = 1000nF
1n = 1000pF
Capacitors with a nominal capacity of the actual power capacity, said the deviation error, allowing the deviation of the accuracy of that.
Accuracy class and allow the relationship between error: 00 (01) - ± 1%, 0 (02) - ± 2%, Ⅰ - ± 5%, Ⅱ - ± 10%, Ⅲ - ± 20%, Ⅳ - (+20% -10%), Ⅴ - (+50% -20%), Ⅵ - (+50% -30%)
General capacitors used Ⅰ, Ⅱ, Ⅲ level, electrolytic capacitor used Ⅳ, Ⅴ, Ⅵ level, according to use select.
2, rated voltage
At the lowest temperature and the ambient temperature can be rated for the highest increase in the capacitor voltage DC RMS, the general direct mark on the shell in the capacitor, if the voltage capacitor over the pressure, capacitors breakdown, causing permanent damage to be repaired.
3, insulation resistance
DC voltage increase in capacitance, and a current leakage, both known as the ratio of insulation resistance.
When the smaller capacitor, the capacitor depends primarily on the surface, and capacity> 0.1 uf, the main medium depends on the performance, the smaller the better the insulation resistance.
Capacitance of the time constant: to appropriate assessment of large-capacity capacitors in the insulation and the introduction of a time constant, the equivalent capacitance insulation resistance and capacity of the product.
4, loss
Capacitance in the electric field, in units of time due to fever called by the consumption of energy loss. Various provisions of the capacitor are in a frequency range of allowable loss, the loss mainly by the capacitor dielectric loss, conductivity and capacitance loss of all metal parts caused by the resistance.
The role of the DC market, the loss to the capacitor leakage in the form of derivative losses, the general smaller, in the role of alternating electric field, the capacitance of the leakage and loss is not only derivative, but also the polarization and the establishment of the cyclical process.
5, the frequency of
With the increased frequency and capacity of electric capacitors general decline in the present law.
