How to Check Triac's Triac's Triggering Capability with Digital Multimeter
Using the hFE socket of the digital multimeter, the triggering ability of the triac can be easily checked. The method is shown in Fig. The picture shows the shape of a small plastic-encapsulated bidirectional thyristor BCR1AM made by Japan's Mitsubishi Corporation. The side with the word is the front, and the pins are T1, T2, and C from left to right. The forward average current of this tube is IF=1A without heat sink. Take a digital multimeter (such as DT-830) and set it to the "NPN" gear, so that the G pole of the triac is open, the T2 pole is connected to the "C" hole through the current limiting resistor R (about 300Ω), and the T1 pole is connected to the "E" hole through the wire. "hole. The role of the resistor R here is to prevent the hFE from being overloaded. The circuit is shown in the figure, at this time the digital multimeter shows the value "000", indicating that the triac is in the off state. Then use a wire to short the G pole and the T2 pole, use +2.8V on the "C" hole as the trigger voltage, and the displayed number immediately jumps from "000" to "578", indicating that the triac has been turned on. Test again according to the picture, the displayed value is from "000" → "428. Prove" that the triac can conduct in two directions, and the quality is good.
