how to detect the four end small power thyristor?
how to detect the four end small power thyristor?
To detect the unidirectional conductivity of PN junction,the multimeter is placed in RX 1K block,and the positive and negative resistance between A-GA,GKGA and Gk-K are measured.The resistance listed in Table should be met.If the positive and negative resistance values of a pair of electrodes are very small or very large ( that is,the difference between positive and negative resistance is very small ),it shows that the unidirectional conductivity of the PN junction is poor even it has been broken down or burned. It can't be used.
Detection of triggering turn-on performance 1 Detection of GA pole trigger capability. The multimeter is placed in RX1kQ block,the black pen is connected to the A pole,the red pen is connected with the K pole,the resistance should be infinite,that is,the pipe is turned off.Use the red stylus tip for a short connection to the K-pole and the GA pole ( note that the red pen should always be in contact with the K pole ),plus a negative pulse to the GA pole,at this time if the multimeter pointer is substantially the right swing, the resistance decreases rapidly,and the tube is triggered to turn on,and the performance is good.If the needle does not move,the tube GA pole trigger ability is not normal. Detection of GK Pole Trigger Capability.The multimeter is placed in RX 1kQ block,the black stylus is connected to the A pole,the red pen is connected with the K pole,and the resistance is infinite,which indicates that the pipe is in the off state.Using the black pen tip,the A pole and the GK pole are short-circuited ( note that the black stylus should always be in contact with the A pole ),which is equivalent to adding a positive pulse to the Gk pole,at this time, if the multimeter needle is placed to the right with a large margin,the resistance value decreases rapidly,and the pipe is triggered to conduct, and the performance is good.If the needle does not move,the GK pole trigger ability is not normal.
Detection of turn-off performance.The detection of GA plus positive pulse detection turn-off capability and GK pole plus negative pulse detection turn-off capability is based on " detection of GA pole trigger capability "or"detection of GK pole triggering capability " the method causes the tube to be in a conducting state,and then uses the wire or the black pen tip to connect the A pole to the GA for a short time and disengages immediately,the black stylus is always in contact with the A pole ),which is equivalent to adding a forward pulse to the GA pole,at this time if the multimeter needle is rapidly turning to the left to infinity,it is proved that the ability of the tube GA to turn off is normal,otherwise,the performance of the pipe tested is not good.Use a wire or a red pen tip to connect the K pole with the Gk and release it immediately ( note that the red stylus should always be in contact with the K pole ),which is equivalent to adding a negative to the GK pole to the pulse,at this time the multimeter needle quickly turn to the left to infinity,proving that the tube GK shutdown capability is normal, otherwise,it shows that the performance of the pipe is not good.4 Detect the reverse conduction characteristics ( reverse conductivity ).When A and GA,K and Gk are shorted respectively, at this time,there are only two PN junctions in parallel between A and K, A pole is connected to the negative pole of PN junction,and K pole is the positive pole of PN junction.The multimeter is placed in RX1k.2 block,first with a red pen and A pole, black pen and K pole,the value of the resistance should be the number of dry Europe;then exchange the pen position for the measurement,the resistance value should be infinite.