Capacitance  refers to the ability to hold a charge. It is a medium for realizing the storage and release of static charges, with the characteristic of permanent charge storage. Capacitor components are widely used in power supply filtering, signal filtering, signal coupling, resonance, filtering, compensation, charging and discharging, energy storage, and power separation in circuits. According to its ability to accommodate charges, it is generally measured in Farads, and the international unit is Farads. Therefore, capacitors are essential components for electronics and power.
The role of capacitors: Bypass capacitors and decoupling capacitors are two devices that provide energy storage for local devices. Bypass capacitors can reduce load demand, make the output of the voltage regulator smooth, similar to a small rechargeable battery, and can be discharged and charged. The decoupling capacitor can smooth the edge signals of the device, so as to prevent the input signal from being too large and causing noise, and filter out interference in the output signal.
Large capacitors filter low frequencies, small capacitors filter high frequencies, filter out interference in the input signal, and the smaller the impedance, the higher the frequency passed through. Energy storage capacitors can collect charges and transfer them to the output end of the power supply. They can be units, parallel or series, to meet different power requirements. Therefore, measure capacitance is very important.
Capacitor meter is an important test instrument for detecting the parameters of capacitors in power supply engineering. It can accurately detect the capacitance of capacitors, test their characteristic parameters and accuracy, and ensure the normal operation of circuits. It uses an adjustable bridge circuit to measure the capacitance of the capacitor, and can better adjust the capacitor according to the test results to reach the best working state.
Working principle of capacitor meter:
The capacitor meter is a test instrument that uses synchronous sampling technology of standard and test capacitors, fault diagnosis procedure and fully automatic measurement process. It is not affected by the fluctuation of the power supply voltage, and can accurately and reliably measure resistors and capacitors, with high stability and repeatability.
Features of capacitor meter:
Capacitor meter can conveniently and quickly measure a single capacitor on site, without removing the connecting wire, thus avoiding a lot of time consuming work and damaging the capacitor. In addition, the capacitor meter will output a higher voltage than the capacitive table, which can improve the fault detection efficiency. In addition, the capacitor meter can not only measure capacitance, but also measure the inductance value of resistors.
LS6515EN Capacitor meter
A deeper understanding of the working principle of capacitor meter:
The capacitor meter directly measures the capacitive current from the secondary side of the power distribution PT, which makes the test safe, simple and fast, so that the instrument does not need to communicate with the primary side and can accurately and reliably monitoring data, and without making complicated safety measures and waiting for lengthy dispatch command. In addition, the capacitor meter injects the harmonic test signal at the PT’s open triangular junction, not only will not cause any influence to the relay protection and PT itself, but also avoids the 50Hz power frequency interference signal, the output end withstands the AC voltage of 100V, the system has single-phase grounding fault, and will not damage the PT and tester, making the test results more accurate and reliable.
Measurement method of capacitor meter:
This introduces the measure capacitance method of fixed capacitors from 10pf to 001uF. First of all, check the capacitors below 10pf, which can be qualitatively checked using the R * 10k gear of the universal meter, to determine whether there is leakage, internal short circuit or breakdown phenomenon of the capacitor; secondly, 10pf to 001uF fixed capacitors, universal meter should select R*1k gear, using two transistors (passing current should be small, type such as 3DG6, β value greater than 100), and red, black pens of multi-functional meter, respectively Connected to the emitter and collector of the bi-directional tube, to determine whether there is a charging phenomenon, and then determine its quality.
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