Inspection method of rectifier diode

First, remove all the rectifying diodes in the rectifier and use 100 × R or 1000 × R ohm gear, measure the two outgoing lines of the rectifier diode (one for the head and one for the tail). If the two measured resistance values differ greatly, for example, the high resistance value is as high as several hundred K Ω to infinity, while the low resistance value is only several hundred Ω or even smaller, it indicates that the diode is good (except for the diode with soft breakdown). If the two measured resistance values are almost equal and the resistance value is small, it indicates that the diode has been broken down and cannot be used. If the resistance measured twice is infinite, it indicates that the diode has been internally disconnected and cannot be used.