How to distinguish the quality of the rectifier bridge?

How to distinguish the quality of the rectifier bridge?

As a power component, the rectifier bridge is widely used in various power supply equipment. Therectifier bridge is the most commonly used circuit that uses the unidirectional conductivity of the diode for rectification, and is often used to convert alternating current into direct current. So how to distinguish the quality of the rectifier bridge.

As a power component, the rectifier bridge is widely used in various power supply equipment. The rectifier bridge is the most commonly used circuit that uses the unidirectional conductivity of the diode for rectification, and is often used to convert alternating current into direct current. So how to distinguish the quality of the rectifier bridge.

     If individual rectifier bridge labels cannot be identified for some reasons, the following two methods can be used to identify them:

     1. Appearance discrimination method. The full bridge consists of four diodes and has four pins. The connection point of the negative poles of the two diodes is the "positive pole" of the DC output terminal of the full bridge, and the connection point of the positive poles of the two diodes is the "negative pole" of the DC output terminal of the full bridge. Most rectifier full bridges are marked with "+", "-", and "~" symbols. (where "+" is the positive pole of the rectified output voltage, "-" is the negative pole of the output voltage, and "~" is the AC voltage input terminal), it is easy to determine each electrode.

     2. Multimeter detection method. If the positive and negative polarity marks of the components are blurred, a multimeter can also be used to detect them. When testing, set the multimeter to the "R×1k" gear, connect the black test lead to a certain pin of the full bridge component, and use the red test lead to measure the remaining three pins respectively. If the measured resistance values are all infinite, then the black test lead The connected pin is the positive pole of the DC output of the full bridge component; if the measured resistance values are all in the range of 4~10kΩ, then the pin connected to the black meter is the negative pole of the DC output of the full bridge component, and the other two The first pin is the AC input pin of the full bridge component.

     During detection, the forward and reverse resistance values of each rectifier diode between the "+" pole and the two "~" poles, between the "one" pole and the two "~" can be measured by a multimeter (the same as the measurement method of ordinary diodes) ) is normal, you can judge whether the full bridge is damaged. If the measured forward and reverse resistance values of a certain diode in the full bridge are both 0 or infinite, it can be judged that the diode has been broken down or damaged by an open circuit.