Electrolytic capacitor is an important component of the LED display. To choose a right electrolytic capacitor is really essential, then what is the probably one for LED electronic display? How can we detect it ? VERYPIXEL makes the following 3 ways to help you of  the above questions for your references.

1. Gear selection. The capacity of electrolytic capacitor usually bigger than fixed capacitors. So when measuring, we should choose the appropriate range for the different capacity. In general, a 1~100μF capacitor can use Rx100 or Rx1k block measuring; Over 100μF capacitor can be measured with Rx100 or Rx1 block.

2.Polarity discrimination. According to the length of pins to distinguish positive and negative of a electrolytic capacitor, the longer pin is positive side and the opposite is the negative side. We can also use the above theory to measure the leakage resistance. That is check any drain resistance,then exchange the pen to measure again. On these two measurements, the larger resistance use a black pen which is positive and red pen connect to the negative. Please pay attention that when testing, you have to record the swing pointer to the right and repeat exchange pen touch capacitor two pins until to confirm the capacitor no charging.

When tested using the above method , the operation should be properly. Do not use two fingers simultaneously touch the lead 4 pins of the measured capacitor, otherwise, human body’s resistance will affect the accuracy of the test data. When Shenzhen LED display manufacturers doing a Rx10k block multimeter to testing, if you use your finger to touch the pins or mental part, it will make the swing pointer back to the position less than infinity, which could misunderstand the inspector. When use a digital multimeter and bridge testing, you can inserted capacitor directly into the socket and then place the instrument in an appropriate block to read out the capacity. 

3. Measuring the leakage resistance. Like mentioned above, the red pen of LED electronic displays capacitor multimeter connect to negative and black pen to positive. In the instant touching, the multimeter pointer turns right substantially. For the same power block, the more swing extent, the bigger capacity is. When the swing pointer turns left slowly stop in a position, that is the forward leakage resistance of the electrolytic capacitor. The larger this value is , indicating that the leakage current is smaller, the better the performance capacitor is. Exchanging the red & black pen repeats the above procedure. The measured resistance is reverse leakage resistance of electrolytic capacitors,this value is less than the positive drain resistance. In the practical using, the leakage resistance of the electrolytic capacitor can not be too high otherwise it can not be able to work normally. In the testing, if the forward and reverse phenomenon no charge, which means the capacity is disappearance or internal circuit break. If the resistance is small or zero, which means the large capacitor leakage or breakdown and can not use any longer.

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