How to detect a one-way thyristor?
How to detect a one-way thyristor?
Determination of appearance recognition of each electrode
Common unidirectional thyristor electrodes are arranged as shown in Figure.
multimeter test.It can be seen that the gate G and the cathode K are a PN junction,and there are two anti-polarity PN junctions between the anode A and the gate G.Therefore, using the multimeter RX100 block can be easily determined to go out of the pole G, cathode K and anode A.The black stylus is connected to an electrode,and the red stylus touches the other two electrodes in turn.If the measurement results have a resistance value of hundreds of Europe,you can determine that the black pen is connected to the gate G.In the measurement of several hundred ohms,the red pen is connected to the cathode K, and the other electrode is the anode A.( a and K,G positive, and anti-are all impassable. ) to judge the trigger ability of good and bad test.According to the cut-off condition of one way thyristor,it can be divided into the following
It is detected in three cases.
use the multimeter to test. Put the multimeter in the RX10 gear,the red pen is connected to the cathode K,the black pen is connected to the anode A,and the multimeter pointer does not move at this time. Contact the gate G with a black pen. When the black watch moves away from the anode A, the gate G will be short circuited with the anode A, that is, a positive trigger voltage is added to the gate G. At this time, the multimeter pointer is clear
It swings to the right and stops at a few euro to + a few Euro points, indicating that the thyristor is triggered by positive triggering. Then, keep the red and black pen connection to the same, leave the black pen out of the gate G (the black pen can not leave the pole A during the movement), and if the pointer of the multimeter remains in the position of several Europe to dozens of Europe, it shows that the thyristor is in good performance; if the needle is returned to zero, it is bad.
Test by test circuit method.The test circuit of the thyristor is shown in Figure 8-4. Using this circuit,we can quickly find out the polarity of single (double) thyristor and judge whether it is good or bad.In Figure,A (T2),K (Tj) and G are three small jacks respectively.LED is a red LED and E is 6~9V.
Stack the battery,AN is a small open button.The use of the method is as follows.
determines the unidirectional thyristor polarity.If the three feet of the unidentified polar thyristor are inserted at random in three holes,if LED immediately lights up,it shows that the A hole is inserted in the G pole (the control pole), the K hole is inserted in the K pole (the cathode),and the G hole is inserted in the A pole (anode).If LED is not inserted after the insertion,press AN and LED to light up.After releasing AN,the LED luminescence indicates that A hole is A pole,K hole is K pole, G hole is G pole.In other cases,it is easy to judge according to the principle of work. B.Judge the quality of a one-way thyristor.The A pole,K pole and G pole are inserted into A,K,G three holes,respectively.The LED should not be bright,press the AN to release,and the LED will be lit until the power is cut off,at this point the device is shown to be good.3 Use the digital multimeter to detect.Dial the digital multimeter to the diode block,and the red pen is arbitrarily fixed on a pin,and the other two pins are contacted in turn with the black pen.If in two tests,the display value is less than 1V at a time,and the overflow symbol"OL"or"1"is displayed for another time ( depending on the different digital multimeter ),indicates that the pin of the red pen is the cathode K.If the red stylus is fixed to a pin,the value of the black stylus connected to the second pin is 0.6 ~ 0.8V,and the black stylus is connected to the third pin to show the overflow symbol " OL " " or " 1 ",and when the pin of the red pen is adjusted to the second pin connected to the black pen,the value of the display becomes from 0.6 to 0.8V into an overflow symbol"OL "or "i1 "can be determined that the thyristor is a one-way thyristor,in which the pin of the red pen is the cathode K, and the second pin is the gate G,the third pin is the anode A.In the above process, no matter how the pin is changed,the overflow or resistance is shown to be very small, and the thyristor is bad.