Search results
Results from the WOW.Com Content Network
Capacitors and inductors as used in electric circuits are not ideal components with only capacitance or inductance.However, they can be treated, to a very good degree of approximation, as being ideal capacitors and inductors in series with a resistance; this resistance is defined as the equivalent series resistance (ESR) [1].
Measuring ESR can be done by applying an alternating voltage at a frequency at which the capacitor's reactance is negligible, in a voltage divider configuration. It is easy to check ESR well enough for troubleshooting by using an improvised ESR meter comprising a simple square-wave generator and oscilloscope, or a sinewave generator of a few tens of kilohertz and an AC voltmeter, using a known ...
The ESR represents losses in the capacitor. In a good capacitor the ESR is very small, and in a poor capacitor the ESR is large. However, ESR is sometimes a minimum value to be required. Note that the ESR is not simply the resistance that would be measured across a capacitor by an ohmmeter. The ESR is a derived quantity with physical origins in ...
The ESR represents losses in the capacitor. In a low-loss capacitor the ESR is very small (the conduction is high leading to a low resistivity), and in a lossy capacitor the ESR can be large. Note that the ESR is not simply the resistance that would be measured across a capacitor by an ohmmeter. The ESR is a derived quantity representing the ...
When the power source delivers current, the measured voltage output is lower than the no-load voltage; the difference is the voltage drop (the product of current and resistance) caused by the internal resistance. The concept of internal resistance applies to all kinds of electrical sources and is useful for analyzing many types of circuits.
Capacitance is the ability of an object to store electric charge. It is measured by the change in charge in response to a difference in electric potential, expressed as the ratio of those quantities. Commonly recognized are two closely related notions of capacitance: self capacitance and mutual capacitance.
A capacitance meter is a piece of electronic test equipment used to measure capacitance, [1] mainly of discrete capacitors. Depending on the sophistication of the meter, it may display the capacitance only, or it may also measure a number of other parameters such as leakage , equivalent series resistance (ESR), and inductance .
The theoretical treatment of devices such as capacitors and resistors tends to assume they are ideal or "perfect" devices, contributing only capacitance or resistance to the circuit. However, all physical devices are connected to a circuit through conductive leads and paths, which contain inherent, usually unwanted, inductance.