Methods for detecting IGBT modules

Static measurement: put the multimeter in the multiplication 100 position, measure the resistance with the black probe connected to terminal 1 and the red probe connected to terminal 2, the resistance displayed should be infinite; swap the probes, the resistance displayed should be around 400 ohms. Use the same method to measure the resistance with the black probe connected to terminal 3 and the red probe connected to terminal 1, the resistance displayed should be infinite; swap the probes, the resistance displayed should be around 400 ohms. If the above situation is met, it means that there is no obvious fault in the two units of this IGBT .

Dynamic test: put the multimeter in the 10K gear, connect the black probe to terminal 4, the red probe to terminal 5, the black probe to terminal 3 and the red probe to terminal 1, the resistance should be 300-400Ω, swap the probes and there is still about 300-400Ω resistance, indicating that the IGBT unit is intact.

Use the same method to test the IGBT between terminals 1 and 2. If it meets the above conditions, it means that the IGBT is also intact.

Set the multimeter to the R×10KΩ position, connect the black test lead to the drain (D) of the IGBT, and the red test lead to the source (S) of the IGBT. At this time, the pointer of the multimeter points to infinity. Touch the gate (G) and drain (D) with your fingers at the same time. At this time, the IGBT is triggered to conduct, and the pointer of the multimeter swings to the direction of smaller resistance and can stop and indicate a certain position. Then touch the source (S) and gate (G) with your fingers at the same time. At this time, the IGBT is blocked and the pointer of the multimeter returns to infinity. At this time, it can be judged that the IGBT is good.

Note: If you make a second measurement, you should short-circuit the source (S) and gate (G).

Any pointer multimeter can be used to test IGBT. When judging the quality of IGBT, be sure to set the multimeter to the R×10KΩ position, because the internal battery voltage of the multimeter below the R×1KΩ position is too low, and the IGBT cannot be turned on when testing the quality, and the quality of the IGBT cannot be judged.

Methods for judging IGBT

1. Determine polarity

First, set the multimeter to the R×1KΩ position. When measuring with the multimeter, if the resistance between one pole and the other two poles is infinite, and the resistance between the pole and the other two poles is still infinite after swapping the test leads, then this pole is determined to be the gate (G). Measure the other two poles with the multimeter again. If the measured resistance is infinite, the resistance is smaller after swapping the test leads. In the case of measuring a smaller resistance, the red test lead is connected to the collector (C); the black test lead is connected to the emitter (E).

2. Judge good or bad

Set the multimeter to the R×10KΩ position, connect the black test lead to the collector (C) of the IGBT, and the red test lead to the emitter (E) of the IGBT. At this time, the pointer of the multimeter is at zero. Touch the gate (G) and the collector (C) with your fingers at the same time. At this time, the IGBT is triggered to conduct, and the pointer of the multimeter swings to the direction of smaller resistance and can stop and indicate a certain position. Then touch the gate (G) and the emitter (E) with your fingers at the same time. At this time, the IGBT is blocked and the pointer of the multimeter returns to zero. At this time, it can be judged that the IGBT is good.

3. Any pointer multimeter can be used to detect IGBT.

When judging the quality of IGBT, be sure to set the multimeter to the R×10KΩ range, because the internal battery voltage of the multimeter below the R×1KΩ range is too low, and the IGBT cannot be turned on when testing the quality, and the quality of the IGBT cannot be judged. This method can also be used to test the quality of power field effect transistors (P- MOSFET ).