How to use pointer multimeter to judge the capacitance value and the capacitance of large capacity electrolytic capacitors

       The method of judging the capacitance value of electrolytic capacitor by using the resistance comparison method of pointer multimeter.

       I. methods of measurement

       For the capacitance value of electrolytic capacitor, the resistance value measured by multimeter can also be compared with the measured data of electrolytic capacitor listed in Table, and the capacitance value of the capacitor can also be obtained.

       Second, the issues that need to be explained.

       When comparing and testing, if the capacitor has just been removed from the circuit, it should be discharged before it can be measured so as not to damage the multimeter. The low voltage capacitor with small capacity can discharge its two pins short, and the high voltage capacitor with large capacity can be discharged by load, and the concrete method is the same as above.

      A method for measuring the capacitance of large capacity electrolytic capacitors using a pointer multimeter.

      For tens of thousands of microfarads of large capacitors, it is impossible to measure their capacitance with general measuring instruments (the maximum digital multimeter can only measure 20pF, and the pointer multimeter can only be judged by observing its charge and discharge).                    However, with a pointer multimeter combined with a timing watch (can also use the mobile phone stopwatch display function), can also more accurately measure the capacitance of tens of micrometers, the specific methods are as follows.

      First, use resistance gear to charge.

      Taking the 500 multimeter as an example, the measured capacitance is first charged with Rx1 or Rx10 gear position, that is, the red watch pen of the multimeter is connected to the negative pole of the capacitor and the black watch pen is connected to the positive pole (see figure 1), when the pointer is returned to infinity, remove the watch pen from the capacitance.

     Second, the voltage block discharge is adopted.

     Quickly dial the multimeter to DC2. 5V gear, first connect the black watch pen to the negative pole of the capacitance after charging, in the red watch pen on the capacitance positive electrode for discharge, write down the time to, at this time the multimeter pointer will fall down from 1.5V. The larger the capacitance, the slower the decline. Once the pointer falls back to 0.55V, the time t is recorded, and the measured capacitance C is

               C =20(t1-t0) (μF)

               C = 20 (t1-t0) (μ F)

In other words, the discharge time per second is equivalent to 20 μ F capacitance, and the conversion is very simple.

       If you want to know more, our website has product specifications for electrolytic capacitors, you can go to ALLICDATA ELECTRONICS LIMITED to get more information