How to measure unidirectional thyristor with digital multimeter
Unidirectional thyristor performance identification
One-way thyristor, referred to as thyristor (SCR), formerly known as thyristor, is a controllable rectifier component. Its circuit symbol is shown in Figure 1. A is the anode, K is the cathode, and G is the control electrode.
Unidirectional thyristor performance identification
One-way thyristor, referred to as thyristor (SCR), formerly known as thyristor, is a controllable rectifier component. Its circuit symbol is shown in Figure 1. A is the anode, K is the cathode, and G is the control electrode.
(1) Use the red meter rod to make fixed contact with any electrode, and the black meter rod contacts the other two electrodes respectively. If it displays 0.2~0.8V at a time when touching one electrode, and overflows when touching the other electrode, the red meter The rod is connected to G. When the display overflows, the black meter rod is connected to A, and the other pole is K. If the measured result is not the above, you need to replace the red meter rod with the electrode and repeat the above steps until the correct result is obtained.
(2) Determine the triggering characteristics. The test current that the diode block of the digital multimeter can provide is only about 1mA, so it can only be used to examine the triggering ability of low-power unidirectional thyristors. The operation method is as follows: Use the red meter rod to keep contact A unchanged, and the black meter rod to contact K. At this time, overflow (off state) should be displayed. Then touch the red meter rod to G while maintaining the connection with A. At this time, the displayed value is generally below 0.8V (turns to conduction state). Then remove the red meter rod from the control pole and the conduction state will continue to be maintained. If this is true after repeated tests, it means that the tube trigger is sensitive and reliable. This method is only suitable for tubes that maintain a small current.
