I am an Electrician/ Instrumentation Specialist/ PLC Programmer and I have been working with vfd's for years. And have encountered many of these issues. But I have never had it explained to me so eloquently. Thank you, you have made me smarter......
@earledaniels45392 жыл бұрын
As an Electrical Design Engineer for motor systems, this is the best video I have seen on this topic. Your delivery method was on point ; clear explanations without over complicating things.
@stephenstephenson6614 Жыл бұрын
Your the best electrical teacher I’ve ever seen. Thank you very much from Dallas Texas!
@jacobbieganowski91362 жыл бұрын
Please for the love of God keep posting. I get many careless instructors who shouldn't even be teaching. You're such a great help to us all, I've got my whole class into these videos!
@brandonpieplow92078 ай бұрын
I work for a shop building control panels for exactly the application you described here: VFDs running ventilation fans. We recently built an order of panels that contained huge line reactors. I never understood exactly what they were doing until I found this video. Thanks so much!
@ferhatnusreturuc1809 Жыл бұрын
thank you Dave, very clearly explanation as always...
@AB-mx9lx Жыл бұрын
In 11 minutes you explained my whole semester ....very bad college teacher I had...plus I have to pay for an awful teacher that did not know right from left...Thanks!!...you are making a positive impact for all the electrical trade and design engineers ...
@Sherlock_Ohms3 жыл бұрын
Best explanation on KZbin, as well as your other vids. Please do not stop making them.
@therealprofessor976 Жыл бұрын
You are a great teacher and I wish you were my teacher.
@wtar84699 ай бұрын
Amazing explanation. One million of thanks
@pafou2 жыл бұрын
I think I might finally have found the best channel teaching these concepts. Clear, concise, practical oriented (as opposed to overly abstracted, unfortunately too common usually in physics teaching) and simply put. Already knew this but needed some clarifications that you provided in a short amount of time, which is greatly appreciated ! Subscribed. Thank you sir.
@jayecheverria24545 ай бұрын
Awesome videos
@TheAbaker872 жыл бұрын
Hi, Dave! I'm a motor engineer and regularly work with a VFD. This is a fantastic explanation of function of a VFD and I had to share it with my coworkers. Keep up the fantastic work!
@grantwhebell7730 Жыл бұрын
Years ago we had major issues, fractional horsepower motors driven by VFD's with very long runs. Killed several motors until we installed output reactors . Reflective wave !
@midkort Жыл бұрын
I love your explanations. Thank you sir!
@tarekcharafeldine8534 Жыл бұрын
You make things easier... Thank youuuuuuu
@garbo8962 Жыл бұрын
Retired from a very large hospital/research center that had over 500 VFD'S from 2 to 1,750 HP. Most had line reactors .. Newer drives had fancy reactors that were in panels with 1 or 2 contractors and capacitors. One boss always insisted that we ring out & megger line reactors while troubleshooting drives. Think I might have checked two because good ball was standing there. We had a great drive tech who only worked on drives for over 20 years and asked him if he ever came across a bad or open line reactor. Told me nope and they are bullet proof. In a new 12 story building all motors 60 HP & larger had 18 pulse drives at pit out line reactors . Luckily all but cooling tower drives were within 75' of motor and used common building wire between drive & motor ( THHN/THWN ). nice vid.
@amramjose2 жыл бұрын
I never thought a subject like this could be taught with little to no math, but this is outstanding, clear and intuitive! Great job, Mr Dave.
@therealprofessor976 Жыл бұрын
I came here on a search for info about saturable reactors, but I stayed here for the lesson.
@denislemelin7653 Жыл бұрын
Great stuff !
@idealalaska82593 жыл бұрын
Fantastic explanation. Very clear and helpful.
@jasonjohnsonHVAC3 ай бұрын
Carrier frequency, harmonics.....lots to learn
@yunusbhadarka6006 Жыл бұрын
Very nice sir
@McKuc18 күн бұрын
Good video! 👍
@motifes76 Жыл бұрын
Awesome explanation
@dennishillman3502 Жыл бұрын
Great video!
@JOHNTHE8TH15 ай бұрын
Common mode current will be induced into the rotor of an induction motor, this current has to go back to the neutral of the source, this path is usually goes through the bearings causing damage and a short life. Use a ground brush on motors above 150hp😀
@ranjan14362 жыл бұрын
You make things look so easy, Great?
@ziyashirinov6283 Жыл бұрын
Great video Dave! thanks for your effort.
@chandikasudulkiriella12602 жыл бұрын
Simply Awesome...!!
@kamelageorgemorena4293 Жыл бұрын
This is good explanation
@alikinu86303 жыл бұрын
smellss quality here! keep doing it!!!!!!!
@CillBinton3 жыл бұрын
Thanks!
@yusprogres5271 Жыл бұрын
Yes
@kimremyholtet87659 ай бұрын
Hi. Good vid. I have a question about a reactor and the use of it. Lets say after the power grid, in normal installation (here in Norway 400V, 50Hz TN-C-S 3 phase). Where I may have som issues about short circuit currents (above 60-70kA). Is it normal in the US, or other parts of the world using a reactor to lower the max short circuit current infront the main panel board for instance? It accured to me when I searched around on the internett and found your video. You see, I am a installer (not a word for it in english as I know about. But it is in northern europe a person qualified to have the certificates and government passed exams after education to make DOC's for electrical installations). I am responsable of design and build electrical installations as the "installer" in my company. Anyway, I have to lower some short circuit currents. In most cases this isnt a big problem to solve with coordination of the breakers to make them have cascade (backup) functions to eachother. But in this case, we are so close to the transformer, so I cannot really make this right now. It might help if I have the voltage increase by over 7.5% from the transformer when short circuiting. But that means I have to change transformers as well. Might be hard to understand, but worth a shot.
@scylam12 жыл бұрын
Hi Dave, thank you so much for the comprehensive explanations. Allow me to ask a silly question; whether the isolation transformer blocks harmonic current generates from the VFD? Thanks 🙏
@madtscientist8853 Жыл бұрын
You could do it so much simpler by just having a 2 coil and 1capacitor and pulsing it at certain frequencies so that it gos at certain speed.
@car9167 Жыл бұрын
I like how you explain things and I have a question. I have a 3phase 380V AC servo spindle + driver but have only 240V single phase AC. I see two options to get 3 phase 380V. One is to use an inverter 240VAC to 3PH 380V and drive the inverter output to a line reactor and feed it into the servo spindle driver. The other option is to use an inverter 240VAC to 3PH 240V and drive a 3PH autotransformer where I get the 3PH 380V. The 240VAC to 3PH240V inverters are half the price of the 380V inverter. Which solution would you recommend? Didn't mention the inverters I have are 10KW (I have both already) and the spindle servo motor is 3.7KW but it has a load factor of 200%
@fernandoorige73102 жыл бұрын
I don't know if my question could be appropriate, but let me ask you: I never had the opportunity to make some measurements. When some running capacitor is lower (microfarad) than the specified, I know that a motor can still be running, but the question is: can it use more energy to run? and, in case of start capacitor, e.g., can it compromise the life of a compressor, if the capacitor is below the minimum specified?
@therealprofessor976 Жыл бұрын
I don't know if I'm wrong, but wouldn't a saturable reactor be good for filtering on a VFD? I know at lower frequencies it would be impractical, but I imagine it could be somewhat helpful, even if clunky. I could be wrong though, and the load current might not even need to be filtered at all.
@brianskellenger93444 ай бұрын
🎯
@prodigy2k7 Жыл бұрын
Can you explain how VFDs can have 2 lines and 3 loads? (single phase in and 3 phase out)
@clausvonstauffenberg11872 жыл бұрын
Wow…
@vijithdavis99772 жыл бұрын
Sir iam not able to run an inverter ac on a 5kva sine wave inverter. Inverter transformer is vibrating even at 900 watts and the PF was 83. I had tested resistive load of more than 2000 watts on this inverter. is there anything to do with harmonics, since its an inverter ac which has vfd like thing? also kindly provide the solution. Thanks..