Another pointer multimeter method of testing IGBT tubes
①Judge the polarity. The multimeter is placed in the RXl kQ file, the black pen is fixed on a pin, the red pen were connected to the other two pins, observe the measured data: adjust the two pens, the red pen is fixed in the original black pen connected to the pin, the black pen were connected to the other two pins, if the two measured resistance values are infinity, then the fixed pen is not fixed to the pin for the gate. The remaining two pins and then measured with a multimeter, if the measured resistance value is infinity, adjust the pen after the measurement of the resistance value is smaller: in the resistance value of a smaller measurement, then the red pen is connected to the drain, the black pen is connected to the source.
② Judge the good and bad. The multimeter is placed in the R × 1kΩ file, with the black pen connected to the drain of the IGBT tube, the red pen connected to the source, the multimeter should be infinite. Touch the gate and drain with your finger at the same time, then the IGBT tube is triggered on, the multimeter pointer swings to the direction of the smaller resistance, and can be stabilised at a certain value. Then use your finger to touch the source and gate at the same time, then the IGBT tube is blocked, the multimeter pointer back to infinity. At this point you can judge the IGBT is good.
Multimeter measurement transistor hFE value method
Some multimeters are set to measure the transistor hFE (DC current amplification times), such as MF47 multimeter, MF368 multimeter. When measuring the hFE of the transistor with this kind of multimeter, the three pins of the transistor should be inserted into the corresponding "NPN" or "PNP" (only "N" and "PNP" are used in the MF47 multimeter). " for "NPN" and "P" for "PNP" on the MF47 multimeter, the following is an example) into the sockets e, b and c on the corresponding "NPN" or "PNP" (only "N" is used to indicate "NPN" and "P" is used to indicate "PNP" on the MF47 multimeter, the following is an example), and set the blocking Switch to "hFE" block on the zero, which can be from the dial of the third group (dial marked with hFE on the scale line) can be read directly on the number of current amplification of the transistor measured. But for the MF368 multimeter, the hFE value is read from the fourth (hFESi) scale line for silicon tubes, and from the fifth (hFEGe) scale line for germanium tubes.
