⚡️ FREE CLASS: How to Do a Complete Electrical Installation from Scratch, Easily, Even if You Are Not a Professional Electrician: ➽ https://eletr.co/aula?utm_content=yt1... ------ g1?utm_content=yt1-vd721 g2?utm_content=yt1-vd721 g3?utm_content=yt1-vd721 g4?utm_content=yt1-vd721 ------ c1?utm_content=yt1-vd721 c2?utm_content=yt1-vd721 c3?utm_content=yt1-vd721 c4?utm_content=yt1-vd721 ------ ???? FAAALA ENGEHALL COMMUNITY ???? Join our community on WhatsApp to receive valuable tips and news in the area electrical, important information and much more. ???? ???? https://eletr.co/fala-eng?utm_content= ------ Did you like this video? ???? ✔️ Leave your comment and share with friends ✔️ Follow our networks ➽ https://eletr.co/links - - - - - - - - - - - - - - - - - - - - - - - - - - - - ???? NR10 Course with 20% discount ➽ https://eletr.co/nr10?utm_content=yt1... ------ This one is a contactor, it is an electromechanical device, widely used to control loads in a power circuit from a control circuit. It allows the activation of loads from the polarization of its coil. So, for example, if I need to open and close a three-phase circuit by simply pressing a single-phase button, I use one like this. Let me open it up to explain it better. Here is the contactor inside. Below is the fixed iron, followed by its coil, the spring, and above it is the movable iron. It is connected to the contacts, which are the contactor terminals. Basically, when we press a button, we energize its coil. This is done through inputs A1 and A2, which are the coil's power supply. When this happens, we have an electromagnetic field in the coil that attracts the movable iron, compressing the spring and closing the contactor contacts. This way, we have the passage of electric current through the terminals. That's how it works. Okay, so we've given a basic review of what it's for and how it works. Now I'm going to teach you the technique I told you about! Well, a common problem we find with contactors is the coil burning out. This happens for several reasons, the main one being the time of use. It's normal for this to wear out. But then you must be thinking, the contactor stopped working, I would have to open it to see if the coil is damaged, right André? In parts yes, if the coil is burned out you will need to open it to replace it, but you can find out if the problem is in the coil by doing a simple continuity test, after all terminals a1 and a2 are interconnected through the copper coils that form the coil, take a look: Here I have two contactors, one new and one burned out. In the new one I put the multimeter on the resistance and continuity scale and the test leads go to terminals a1 and a2. See that it shows us a change in the resistance value, in this case it is indicating 516 ohms, this confirms that there is continuity, so this coil is working. Now in the contactor that I know is burned out, look, when I put the test leads on a1 and a2 it does not indicate a change in the ohmic scale, so we have no continuity, so without opening the contactor I know that the coil is defective. And opening the faulty contactor, we can see that its coil is melted, possibly this was an overload, then just replace the coil and that's it, we have a brand new contactor. Another tip that I also give to people is regarding the power contacts. To test the continuity of the power terminals, just press the spring, so we touch the fixed and movable irons and we have the passage of electric current, with the multimeter again on the continuity scale, we have the passage of electric current through these contacts, the operation is very simple.