Learn how to check an igbt using a multimeter. The igbt is abbreviated as Insulated gate bipolar transistors. These are the 3-terminal semiconductor devices used in electrical appliances for fast switching. Devices like amplifiers mostly need them as there is a wide fluctuation in the signals in the amplifier, so a vital component like an Insulated gate bipolar transistor is required to cope with all this change and switch according to the needs of the electrical appliance.
It purposely saves your appliance from any short circuit condition because it is the one that helps to give you the appropriate level of current irrespective of any fluctuation occurring far behind. It saves your connections and provides you with efficient enough electric signals.
How does igbt work?
Before diving into the testing procedure of the igbt, we should first know how the igbt works and the purpose of this component in our electrical appliances. In this way, we can better understand the importance level of these components.
Igbt has three major parts in it. These are the gate, collector, and the emitter.
Igbt performs a dual function. It has gate-drive qualities, just like the MOSFET. The insulated gate bipolar transistors work on the principle of input voltage controlling output current.
It can also perform the function of a bipolar transistor by managing the high current and low saturation of the device. Any appliance that has a high switch repetition rate, just like a UPS or SMPS, has an igbt in it. It makes the appliance more efficient and lowers its unnecessary noise.
Importance of igbt over MOSFET:
Here are some reasons why the MOSFET and other components like BJT are less important than the igbt in electrical appliances nowadays.
- The driving power of the insulated gate bipolar transistors is low, so it is easy to regulate them even in high-voltage appliances, unlike the BJT.
- The current conduction capacity of the igbt is very high, so the blocking skills of this component are far more than even bipolar transistors.
- The on-state current density of igbt is better than other components. In this way, they can have smaller sizes like a small chip. So you will have better functions at a lower price.
Along with all its functions, what will happen to your electric appliances if this insulated gate bipolar transistor component becomes faulty? The entire functions performed by it will get stopped, and it will damage your electric device. More efficiency comes with more care. To save your appliances from any future drastic damage, it is essential to give them a frequent check.
How to check an igbt using a multimeter
Materials required:
- Protective gloves
- Protection glasses
- Digital Multimeter
Preventive measures:
Make sure no electricity supply is reaching the IGBT. Wear protective glasses and gloves to save yourself, as self-safety is very important. Don’t perform any step in a hurry. Be gentle with the process and initiate the testing procedure as given below.
How to check an igbt using a multimeter (Step-by-step guide)
This testing procedure will help you to understand whether your igbt is working well or has become faulty. You can follow this procedure even if your igbt has not shown any false symptoms because, by this, you can get to know even if your insulated GATE bipolar transistor is near to getting faulty.
Turn off the power supply:
Turn off the power supply to your appliance upon which you will perform the test, as here, there is no need for any electricity in the appliance. Make sure that there is no electricity reaching out to your workplace.
Find the igbt circuit:
As you will test the condition of your igbt, the second step is to locate that igbt circuit. Different appliances have different locations for the igbt circuit, but you can identify it by its black-and-white color and connections. Igbt has two connections on the side and six connections on the top. Perform this step carefully because this is the basics of the procedure. If you locate the wrong circuit, the whole test will have 0 output.
Separate the igbt:
As you are going to test igbt, you have to detach it from the appliance. You have to do this after assuring no current passing from the circuit. Remove the connections of the igbt from the appliance and separate it.
Perform the diode test:
For this, take the red lead of the digital multimeter and attach it to the emitter terminal, which is a black lead of your igbt. Turn the digital multimeter selection knob towards the diode mode. Check the results. If you get readings between 0.2 and 0.8, then it means your igbt has the functional protection diode in it.
Gate oxide test:
This test is done to check whether your igbt has been shortened. For this, set the digital multimeter on the resistance mode. With the same connection as above, check the readings. If the multimeter showed any reading except the infinite sign, it means your igbt is working well, and it’s never been shortened.
Test the igbt tester:
Take the igbt tester and attach it with the igbt gate, collector, and black lead. The gate is present right beside the emitter. You can find the collector opposite it. Test them with the digital multimeter. If the light is turned ON, it means there is no fault in your igbt, but if it’s the opposite to it, then it is a clear sign of your faulty igbt.
Final Verdict
The insulated gate bipolar transistors are the ones that increase the efficiency of your electrical appliance. It helps it to not bother under the fluctuating voltage conditions because of which most of our appliances get burned. The short circuit is the major problem nowadays. To overcome this problem, these igb transistors are installed in some high-quality appliances. If you don’t want to lose your expensive electrical appliances and want to increase their value, then keep them a regular check.
Digital multimeters can rescue you under all these problematic conditions. By following the proper testing procedure to check an igbt using a multimeter, you can save the life of your electrical appliances, which have insulated gate bipolar transistors.
