How to test and repair the rectifier bridge?

Last Update Time: 2018-10-26 15:52:31

How to test and repair the rectifier bridge?

Distinguish polarity to place the multimeter in RX1kQ block,and the black stylus arbitrarily connect a pin of the whole bridge component,and measure the other three pins with the red stylus,if the measured resistance is infinite,then the pin of the black pen is the DC output positive pole of the full bridge component;if the measured resistance is 4 ~ 10k2,then the black pen pin is the DC output negative pole of the full bridge component,and the remaining two pins are the full bridge components aC input terminal. RX1kilo-ohm block,red and black markers are measured with two foot forward,anti-resistance.When there are two feet,the two feet are AC input,and the other two are DC output.Measuring the positive and negative resistance of the two output terminals, the meter needle swing resistance value is larger,the black surface pen meets the negative extreme of the DC output,and the red pen is the positive extreme.

Determine the positive and negative resistance of each diode after finding the electrode according to the method mentioned above, and then measuring the diode. If the forward resistance is small, the reverse resistance is infinite, then it is normal, otherwise it will be damaged. Note : for the DC output of the diode is the negative pole of the diode, the DC output is negative as the positive pole of the diode.

Maintenance of the whole bridge and half-bridge component is tested, and if it is confirmed that the PN junction of a diode in the whole bridge and half bridge component is damaged, the following methods can be used for detection. 1 External Diode Method. The diode in the whole bridge and half bridge component is damaged, and can be repaired by a diode between the outer feet of the full bridge and the half bridge component. The voltage and maximum rectification current of the connected diode are required to be caused by the breakdown voltage and rectification current of the full bridge component, and the positive and reverse resistance values are as close as possible to the full bridge component the rest of the diodes are the same, and notice that the polarity can't be reversed. Figure 5-5 shows the damaged full-bridge, half-bridge external diode repair method.

Circuit Utilization Method.If the group of series in the whole bridge component is in good condition,it can be used in the half-bridge full-wave rectifier circuit.