holy wow - normaly you have to watch 3902 youtube-videos in order to get usable information. This was basically the most conscise, information-dense, cometent, no-bullshit-video I might have seen in my life. Respect and thanks.
Very good primer. I recently retired from a controls engineer position. 90% of the motors we dealt with were VFD driven. We would occasionally get away with temporarily driving a non-VFD-rated motor, but that was always a temporary solution, usually ending with the motor getting rewound or outright replaced. One thing we REALLY learned was to install the AEGIS rings on them!!! It's amazing how much damage occurs to the bearings.
Very interesting video which contains very useful information related to the topic of VFD. Probably, this video should be viewed more than one time in order to appreciate all its content. Congratulations for the quality of the video and the information included.
Very good. One of the best and clearest explanations on this topic I’ve seen. The amount of misinformation on TH-cam channels (and elsewhere) is unbelievable, particularly in the area of the purchase and refurbishing of old machines such as lathes, mills, surface grinders and others. Many of these machines are many decades old with three phase motors, and often, people want to use them on single phase. I try to explain why a heavily used motor from 50 to 80 years ago shouldn’t be used with an inverter to vary speeds, but I get pushback. I intend to link to this video from now in. I do disagree with manufacturer labeling where they don’t state inverter ready on the tag. I don’t know why not. It essentially costs them nothing to do so. I bought a motor two years ago that was advertised as such but didn’t say so. I had to call the manufacturer for confirmation. Unfortunately, many motors for sale today were designed before most manufacturers decided to make most of their offerings inverter ready. So if it doesn’t say so, you can’t know if the motor on the shelf is or isn’t. You always have to check. In ten years maybe it won’t be necessary, but for now, it really is.
Hi Mel, thanks for the comment. Glad the video was helpful. You're right, there are still a bunch of non-inverter ready motors out there and it's important to check.
thanks for the info we’ve been installing new roof rooftop units York they come with a drive and after six months we start noticing brand new blower motors started having bad bearings and we didn’t know why with you info we can see the problem
Such a brilliant upload , and thanks so much ! I am trying to specify a VFD for a 3 phase motor which is 2.2kw , 400v , 50hz, but my supply is 220v singlephase . I would be very glad of any pointers
Hi Neil - thank you for the question. It would be worth checking if the motor is 400V only or if it's also wound to accept 200V. Otherwise, I'm not aware of any VFDs that will drive a 400V motor from a 200V supply without the motor being rewound for 200V.
If that is all you have back feed a 5kw transformer. 240/480. Reason for double size is doing so will cause alot of IR sqaure losses in Iron Stack and extra heating. Wont be very efficient but will get the job done. Set motor type to 50hz and motor voltage to 400. Single phase application will also require a line reactor size Full load motor amps plus service factor multplied by 1.73.
I found this useful, really informative, so thanks a lot, I am planning to add a VFD to a lathe motor to get fine adjustment within a speed range, and I already suspected VFDs were not applicable to all motor types, now I have a better idea of what to look for. I would like to have seen some torque vs frequency curves for common motor types to get an idea on how far I should try to push things, but I guess I will find out!
I plan to use a VFD to drive an old 3 phase induction motor on single phase power on a bridgeport mill. This older motor was made in 1987 with E class insulation. A grounding ring would be half the cost of a new motor. Would you recommend just running this one till it dies and then replacing with an inverter rated motor? How long would you expect something like this to run before it dies? Would you expect weeks/months, or would it be more like a few years? Not going to hold you to anything of course, just curious roughly how long you think a motor like this would last in my situation.
Thanks for the question. Running it till it's dead and then replacing with an inverter rated motor is not the worst idea. A shaft grounding ring is not the magic bullet solution to make a non-inverter-rated motor run on an inverter so it's recommended to buy an inverter duty motor. As for life span, due to a lack of standardization for older motors, it's nearly impossible to tell. Some will run smooth for years while others start chugging in weeks. Though from the limited Bridgeport inquiries I've dealt with, they have usually ended up lasting on the order of months. I hope this helps! Happy tinkering. - Keith
We had well over a 100 plain Jane non VFD rated NEMA motors that were installed in the 1970's from 3 to 250 HP that were changed over to drives over 25 years ago. Lucky if we had two old motors a year burn out. Most did have line reactors. Most ran under 90% of rated RPM .
Thanks for the comment. Older motors are a bit of an enigma when it comes to VFD rating. A lot of them were manufactured to a very high standard of workmanship and incorporated insulation/magnet wire that would allow for safe operation under a VFD with sufficient thermal headroom for turndown but at the same time you have plenty of motors that weren't. The nice thing about purpose-built/tested inverter duty motors is the guaranty of safe operation under inverter power. A non-VFD-rated motor would likely have more to gain from a load reactor than a line reactor.
Thanks for the great information. Would MFR-J55WZ0BP-0114 be an okay candidate to control with a VFD? Planning to update my drill press to support low end RPM for punching holes in metal. I can't find the data sheet but there are lots of images of the motor ID plate. Kind regards.
Thanks for the question Rusty! Based on the catalogue number, you are working with a DC motor. To control a DC motor, you'll use a DC drive. VFDs are used on AC motors. Here's an overview of our DC drives available in Canada and the US: www.emotorsdirect.ca/controls/dc-drives
@@rustyshackleford9066 the KB Electronics KBWT-112 would be a good solution for low end torque: www.emotorsdirect.ca/item/kb-electronics-kbwt-112. However, before buying I would first check if this motor has a drive built in. One of my coworkers is a VFD specialist (Ahsan). If you give him a call, he can help you confirm if the motor has a drive built in. He can be reached at 1-800-890-7593 ex 108 and I shared your project details with him.
Can We use Continuous (S1) Duty motor for VFD operation ? We are taking S1 motors with insulated bearing and class F insulation. Both motor and VFD are new.
Great question. All industrial motors built in the last 10-15 years would be VFD rated, you would just need to verify the motor turndown is in the range that you are going to use. Some motors only come with 2:1, 4:1, or 10:1 turndown and you may want to go slower than that.
It's a little hard to tell from the video, but is the main problem with using a VFD that it is not as clean or smooth as true 3 phase? I am thinking of a very narrow application where you would simply want to run 3 phase from a single phase. For instance, if you bought an industrial compressor on the cheap and wanted to use it at home. The VFD would essentially just be a way to use the 3 phase motor on a residential single phase supply. It would be configured once and never change. In this scenario does the VFD negatively effect the motor, or have the potential too? I'm trying to understand if the issues raised in the video are due to the assumption that the VFD will be used to actually vary the motor speed or not. In the scenario I described the VFD would be more like a fancy starter.
Hi Travis, thanks for the question. Due to the way that VFDs reconstruct the power waveform they produce large voltage spikes, these spikes can overwhelm the winding insulation, short them out, and start arcing. The arcs produce heat that further damage/degrade the windings. A similar phenomenon may happen across the bearings. Most manufacturers now use inverter grade magnet wire as standard and this neutralizes the winding arcs. Bearing discharge remains a problem but you can always get a grounding ring. A further consideration is that VFDs are so much cheaper than running a 3 phase line or a rotary converter that you could burn out and replace your existing motor with an inverter grade motor and still have saved money compared to the other options.
Great commentary - thank you. It's great to have such direct presentation. I thought the remarks about fan speed/cooling to be advice that comes from genuine broad expertise about function and life cycle and particularly insightful. I'm curious and would welcome your advice on a matter you cover here. Is conductive grease used to mitigate the potential difference between the armature and motor body? I presume the problem is that the grease isolates the armature from the main body and grounding setup, so becomes a source of heat and grease degrades? I ask this as I am looking at ways to diminish precipitation static in a coffee grinder design where the motor mounts one grinding face and the body of the grinder the other. The bearings are an isolating factor. As coffee is ground static charge accumulation occurs due to the friction. I had thought the use of conductive grease in the bearings would ensure the armature could be grounded more uniformly and reduce static in the ground coffee by dissipating it as it generates. You may not be an expert on coffee but I hope you may have some insights into the ground loop and contribution of the bearings and their conductivity on it in a motor :).
Hi Michael, thanks for your comment. This is the point of conductive grease. Alternatively, grounding rings would also do the same thing. Check out my video on grounding rings for more specifics: th-cam.com/video/olqO0cRvPeI/w-d-xo.htmlsi=xt1VyrcLpSxyzJ4U
@@emotorsdirect Thank you sir. I'll go watch the video you linked :). Have you perchance done any videos on dissipation of precipitation static (P-static) on a single or multi-ground system?
Thank you for this video! I can tell you have a huge knowledge base to draw from. I run an residential HVAC company and I'm getting a bit tired of replacing inverters that are 4500$ our cost due to proprietary software and communication. I feel like it shouldn't be terribly hard to build a system that can use more standard a more standard VFD and maybe simplify everything a bit. One issue I'm running into is that most of this info is directed more to 3 phase input industrial applications. All of our residential service only allows for 240v Single phase. My dream is to build something similar to the Bosch condenser that ramps up and down dependent on refrigerant pressures and doesn't need direct communication with the indoor unit past the signal to turn on and off; but do it with readily available VFDs like industrial Legos. Would you have any advice on what I need to look for in a compatible VFD and Compressor with my single phase limitation?
Hi Scott, thanks for the comment! Wow that's steep - where are you located? The SINUS M series of drives would be perfect for this application. Any of the three phase drives we list, if sized correctly, would also work for a single phase application. Contact our tech team for more support there if needed: www.emotorsdirect.ca/contact-us FYI - we have a few single phase specific videos coming this year - hopefully you'll enjoy those. - Keith
Hi Keith! Please support on this: I have a mini lathe with variable RPM (Paulimot 190-V), just bought it, brand new. Right after pressing the Start button, but BEFORE the motor starts spinning, a high frequency sound appears (10k Hz) and keeps sounding no matter the RPM is, until the lathe stops. Could this be the VFD? How could I diagnose it better? Thx!
Hi Sorin, thanks for the comment. Yes, that is sound of the VFD output's switching frequency. There is really no fix for this outside of isolating the VFD in a box to reduce how much sound gets out.
Hello. I have a Romanian SP81sw bench lathe, it's small with an 80mm universal and it has a 0.37 kw / 380v motor. I only have a 220v network. What power should the VDF have for this motor, should I switch it to a VFD to run on 220v .Thank you!
This comes in handy when you have single phase input (common in residential and some commercial applications). Check out the video I just created on this subject: th-cam.com/video/skEaxx5YJbI/w-d-xo.htmlsi=QHBAtly4EbqMlSWI
Hi Tigalana, thank you for the question. A VFD cannot control how much current a motor draws. Without going into detail, a motor will draw as many amps as it needs in order to turn the load. Under normal running conditions the amp draw is a function of the torque required which often scales proportionally with RPM. The only way I can see a VFD controlling current output is via speed control. VFDs often include current limiting circuits and thermal overloads. So they can stop the motor if amperage exceeds a set amount. I hope this helps!
Would this video be helpful in knowing if you can use pulse width modulation with a motor? I think its an analogous situation. New to electronics, please help
I have a spare 2hp 3ph I want to use but can't find any info on it. The part number is "US Motors p63fte-1793" and I'd like to find the right vfd. Any recommendations?
Hi Scott, did some digging and it looks like this is a TEFC class B insulation motor. Some things to keep in mind: (1) Duty: fan-cooled motors will have cooling issues when slowed, however, the thermal mass of the motor can hold some heat before getting too hot so intermittent use can offset the thermal load. (2) Insulation: though insulation class is a purely thermal standard, it just so happens that when motor manufacturers put in better thermal insulation, they also put in better electrical insulation, so we generally recommend class F and up. Many class B motors will also run fine on a VFD, but it will likely take a toll on some of the mechanical components. (3) Required turndown: since you're considering VSD operation, I'm assuming you want some degree of turndown, but it makes a huge difference for operation if you want a 1:4 turndown vs 1:10 for example. I would say any of our lower-cost VFDs (ex. L510-202-H3-U) would work depending on how often it will be used and the degree of turndown. If you're working with a single-phase supply, go with a TECO Sinus M. This is an off-label application and thus performance and longevity are very application dependant. Your motor may develop a wabble over time, in which case, you could replace that spare motor for a few hundred dollars. Thanks for the comment!
@eMotors Direct Thanks. The motor will be used extremely intermittently, like 5 minutes on and 30 minutes off. And even then, only a few times each day. This is not for a continuous use application. I'll likely only be slowing it to around half speed, maybe a little less, when I do slow it down, and that won't be often. I suppose I could have included all of that in the beginning, but then I may have missed out on some of the info you just shared. Thanks again!
thank you for this insight. my question, is there a way to use a VFD with single phase induction motor 4 poles that uses a centrifugal clutch? i mean, is there a way around it?
Great question. Technically you can. There are TH-cam videos out there that show how to do this. But it's not something we recommend as VFDs and single-phase motors were not designed to be used together in this fashion. It could burn the motor out or it could damage the VFD.
@@emotorsdirect thank you for your reply, i was looking for a VFD to add to my drill press motor, but might be better off with a 3 phase motor first , thanks 👍
Thanks Sir Please i need your help We have 3ph Siemens ex motor 1mj7 310-2cc60-z with 95.7 kw My question could we drive this motor with a vfd or its not supported ?
Hi Basrawwi, thank you for the comment. Most motors built within the last 15 or so years will operate fine on a VFD as higher insulation classes and inverter grade magnet wire are standard practice among higher end manufacturers in the industrial space. The problem here is that I don't see an explicit rating for this particular motor, so its impossible to say how much turndown the drive can handle. Typically at this point, I'd reach out to the manufacturer of the motor to confirm. Siemens may be able to answer this question for you with more certainty if you reach out directly. Siemens recently sold their low voltage line to ABB, so they may also be able to help you out.
@@emotorsdirect Thanks alot Sir, really appreciate your help. actually i tried to get confirmation from Siemens 3 days ago, but i didn't get it yet, may be i need to send them a reminder. Thanks a lot again...
Hello sir this video is very informative. I have some question. How can identify the vfd for a direct drive motor below .5HP motor 140RPM thank you for the help.
Thanks for the comment! We'd need more information on the motor to recommend a VFD. If you answer the questions on this form, I can make a recommendation: www.emotorsdirect.ca/request-quote
These old mechanical variable gearbox motors are non-standard and very old. A VFD would probably work but it's uncertain how long. Since these motors are likely difficult to replace I wouldn't recommend it. You could bypass the J head varidrive entirely and throw in a newer motor however I'd need more details on the project to be sure.
Thanks for the question. Whether any brand would offer a 2000 HP VFD would depend on input voltage. If you want to individually speed control the motors, you will need to use one VFD per motor. If you want to speed control 6 motors on an individual level from a single interface, you will need 6 drives in a master/slave topology with a single drive playing the role of master and controlling the other 5. The only series of drives in our LV(230V-600v) catalogue that WILL DO 2000kw is the cfw11 series: www.emotorsdirect.ca/search?keywords=cfw11
Hi Anas, thanks for the question. VFDs are sized by current. Manufacturers will generally add a horsepower rating with a decent safety factor. Check the FLA on the motor and the rated output current. If the latter is the greater of the two you're doing great.
I really hope you can answer this question: I want to make my home AC condenser compressor variable speed with a VFD. It’s a single phase 220V 1.75 ton 21kBTU compressor so about 2hp. RPM of a residential scroll compressor is about 3,000. I want to vary it to about half. You think I could make it work?
If you run the motor at too high speed, its torque can decrease to the point when it can't maintain rotation and will straight up stop completely, coils will draw too much current and damage VFD and themselves, potentially causing fire. Also if you run it at really extreme speed, and this motor is large, its rotor can just tear itself apart, causing massive destruction to whatever rotor's debris hit.
I have a late 60s 2 speed motor that has been swapped to a drive. When slowing in an unloaded direction (possibly reverse loaded for slowing down with a regen resistor) it chatters and hiccups some runs. I believe the motor is high slip but low info on the data tag. Also possibly a gear box problem. Any suggestions? Thanks for your video.
Hi Rob, this is highly dependent on the type of two speed motor and how the speeds are selected. In order to diagnose a high slip situation, I recommend watching the output current. The magnitude of slip is proportional to torque and thus the output current.
Hello Sir ... I have a concern. My plant has a lot of fluctuating load. The main substation has a lot of fluctuation in amperes. Which we see in the ampere meter. How can we reduce this falctuation load?
Good day.i have an home appliance from europe which power supply is 220v 50Hz.what can i do so that i can use it in my country,without damaging the motor, where our power supply is 220v but 60Hz.thank you in advance and more power.
Hi Jonathan, thanks for the question. You can use a VFD to operate at a higher or lower frequency, but there are some limits. In your case, this should work fine.
Thanks for your expertise. Is it possible to use a VFD on single phase motors. I am setting up an off grid wood machining shop and am trying to size an appropriate generator and hoping to reduce inrush current so I do not need an oversize generator. Any advice would be appreciated. I am going single phase as my existing machines (biggest 5hp) are single phase and because of the wide range of single phase tools available . It will also be used as the backup generator for a solar power system.
I would recommend running a three-phase motor as single phase output VFDs can be expensive and most modern 3 phase VFDs can't run a single phase load due to phase-imbalance-trip circuitry being standard. As for the intuition on not needing to oversize the generator, you are correct that the VFD would reduce inrush. But on the converse, you'd still have to oversize the generator for the harmonic distortion the VFD would produce unless you paired it with line filtering. If you'd like the particulars on any of this, please email us and we can help iron out the full package of things you would need in either scenario.
I have a question for you. I have standard 110 in my garage and I have a 3 phase motor I want to use on an old drill press. The motor is manufactured by “Brown & Sharpe and its 3 phase Alternating current. There are nine, all painted black, wires protruding from the motor. Three sets of two have been twisted together and there are three left alone. Their numbers are 1, 2 & 3. The motors information plate on the exterior of the motor shows that it can be wired 208-220 or 440. Under the 208-220 it shows the following: 3 lead motor 1-2-3 6 lead motor 1-2-3 6-4-5 9 lead motor 1-2-3 7-8-9 4-5-6 So, can my motor support the use of a VFD and if so how do I wire it??? Is my motor VFD compatible? If so, how do I wire it???
Unless the nameplate has some reference to VFD or inverter rating, it is unlikely the motor is rated for VFD use. However, some non-rated motors just happen to be built with inverter grade magnet wire and can function just fine under inverter power with the carrier frequency set low. Unless the motor is somehow uniquely valuable, throwing a VFD on it will restore operation. But this might burn out the motor. A lot of motors made these days are VFD rated, but since it's an older drill press, it's hard to say. Most VFDs will come with a wiring diagram that will walk you though how to hook up the motor.
Hi Jay, thanks for your question. Some single phases motors can be run on a VFD when sized appropriately. However, cap start induction motors like the Leeson 131534.00 cannot, the motor starts on a capacitor and has a switch that bypasses the capacitor at around 80% RPM. This means that if you under-speed it past about 80% the capacitor is brought into the circuit and since the capacitor isn’t rated for continuous operation it will burn out.
VFDs have overloads built into them and will fault out when too much current flows. It's not recommended to use an overload/contactor on the output of a VFD. Thanks for the question!
I couldn't find much information on this motor. I'm assuming this is a discontinued OEM motor. Because it looks older and is ODP, I'm guessing it's not rated for VFD use. It may not have the cooling capacity required to use with a VFD.
You can consider 'horsepower' and 'kilowatts' synonymous in this video. You should size your VFD based on the motor FLA and voltage, not the horsepower (or kilowatts). But generally speaking, we can match motor horsepower to VFD horsepower (ie. 8 HP motor to 8 HP VFD), unless you have an application with a high degree of overload, in which case, you should oversize the VFD. Based on the information, I think your VFD is probably undersized for your motor.
They do have bleed circuits. If this is about letting a drive rest a bit before opening it up to inspect it, the prohibition regarding rest time is to allow the bleed circuit to reduce the stored charge to safe levels.
I have a b a l d o r brand motor it requires vfd the motor is three-phase and it's 200 to 400 volts on the ID tag the question that I have is it powered by 120 volts ac to the vfd to control the motor or does it still need to be hooked to 220 can't seem to figure this part out
Hey Tony, thanks for the question. This will depend on the rating of the VFD. Take this example of this KB drive (www.emotorsdirect.ca/item/kb-electronics-kbda-27d), it is rated for either 115V or 230V input but will always provide a 230V output since it has a voltage doubler for the 115V line. For a drive like this, it can take 115V input and output three phase 230V for a 230 V motor. If your drive doesn't include a voltage doubler, then you will need to provide a 230VB input. I hope that answers your question. - Keith
I'm electrical stupid.. I have a 110 V 3 H.P. 3 phase motor. I want to run it on a regular home single phase system. So I think I need a 110 single phase input, to 110 3 phase output VFD.....are they available... can I do this setup ???
Hi Roger, thanks for the question. 3HP is too large a motor to run on 120 single phase assuming 100% efficiency. A 3HP motor would need 19 amps and most home breakers will be 12 or 15 amp The wiring will be matched to the breaker size. If you are okay with using current limiting on their VFD to effectively turn the motor into a 1.5HP motor then this can work. 120V->120V VFDs don't exist. Most 120V VFDs output 230V through a doubler circuit. Let me know if you have any follow up questions!
Doable, however this will likely reduce the life of the motor if the insulation/magnet wire is not up to snuff. I would need to see the nameplate to provide concrete advice.
@@emotorsdirect I have a seventy year old Delta wound motor. Mortising machine. Heavy duty cast iron frame. Heavy duty bearings. Will it cope with a VFD ? 4 hp , 2850 rpm, .5 hour rating. Is Delta wound less suitable for VFD? It doesn't have a junction box to change to star Delta.
Hi Alex, thanks for the comment! Yes, generally speaking, VFDs can be used with three phase motors. Where are you located? I can point you in the right direction from there.
Hi Rodolfo, Thanks for the tip. You can use the little gear icon and then click 'playback speed' to slow down the speed of the video - I hope that's helpful.
holy wow - normaly you have to watch 3902 youtube-videos in order to get usable information. This was basically the most conscise, information-dense, cometent, no-bullshit-video I might have seen in my life. Respect and thanks.
Hi Klein, thanks for watching! Check my other videos - I'd love to hear your thoughts.
Agreed 👍
@@raphysoucy83 thanks Raphy!
Very helpful
I swear to God
Very good primer. I recently retired from a controls engineer position. 90% of the motors we dealt with were VFD driven. We would occasionally get away with temporarily driving a non-VFD-rated motor, but that was always a temporary solution, usually ending with the motor getting rewound or outright replaced. One thing we REALLY learned was to install the AEGIS rings on them!!! It's amazing how much damage occurs to the bearings.
Thanks for the comment Doug. The AEGIS rings are a life saver 👍
This guy nails it! Great presentation. Thanks from Australia
Thanks Brendan from Australia! - Keith
That is a great profile pic by the way.
Very interesting video which contains very useful information related to the topic of VFD. Probably, this video should be viewed more than one time in order to appreciate all its content. Congratulations for the quality of the video and the information included.
Thanks @stohme! Glad the content was useful. - Keith
I’m a first year electrician apprentice and aspire to get into controls so videos like this are amazing and easy to understand!
Glad it was helpful!
Awesome Keith! fantastic brief on motor compatibility and the initial design criteria for any project!
Thanks for stopping by! Releasing new content soon - stay tuned.
Very good. One of the best and clearest explanations on this topic I’ve seen. The amount of misinformation on TH-cam channels (and elsewhere) is unbelievable, particularly in the area of the purchase and refurbishing of old machines such as lathes, mills, surface grinders and others. Many of these machines are many decades old with three phase motors, and often, people want to use them on single phase. I try to explain why a heavily used motor from 50 to 80 years ago shouldn’t be used with an inverter to vary speeds, but I get pushback. I intend to link to this video from now in.
I do disagree with manufacturer labeling where they don’t state inverter ready on the tag. I don’t know why not. It essentially costs them nothing to do so. I bought a motor two years ago that was advertised as such but didn’t say so. I had to call the manufacturer for confirmation. Unfortunately, many motors for sale today were designed before most manufacturers decided to make most of their offerings inverter ready. So if it doesn’t say so, you can’t know if the motor on the shelf is or isn’t. You always have to check. In ten years maybe it won’t be necessary, but for now, it really is.
Hi Mel, thanks for the comment. Glad the video was helpful. You're right, there are still a bunch of non-inverter ready motors out there and it's important to check.
thanks for the info we’ve been installing new roof rooftop units York they come with a drive and after six months we start noticing brand new blower motors started having bad bearings and we didn’t know why with you info we can see the problem
I'd recommend using a shaft grounding ring to avoid that. Here's more info on: th-cam.com/video/olqO0cRvPeI/w-d-xo.htmlfeature=shared
Excellent video, very informative! Thank you Keith.
Thanks Billy
Such a brilliant upload , and thanks so much ! I am trying to specify a VFD for a 3 phase motor which is 2.2kw , 400v , 50hz, but my supply is 220v singlephase . I would be very glad of any pointers
Hi Neil - thank you for the question. It would be worth checking if the motor is 400V only or if it's also wound to accept 200V. Otherwise, I'm not aware of any VFDs that will drive a 400V motor from a 200V supply without the motor being rewound for 200V.
Have a look if your motor can be configured to run in delta at lower voltage or Y for higher voltage.
If that is all you have back feed a 5kw transformer. 240/480. Reason for double size is doing so will cause alot of IR sqaure losses in Iron Stack and extra heating. Wont be very efficient but will get the job done. Set motor type to 50hz and motor voltage to 400. Single phase application will also require a line reactor size Full load motor amps plus service factor multplied by 1.73.
Very nicely explained - Thank You
Thanks for the comment! - Keith
Would like to see video with cable specs between vfd and motor.
Thanks.
Thanks for the suggestion!
I found this useful, really informative, so thanks a lot, I am planning to add a VFD to a lathe motor to get fine adjustment within a speed range, and I already suspected VFDs were not applicable to all motor types, now I have a better idea of what to look for. I would like to have seen some torque vs frequency curves for common motor types to get an idea on how far I should try to push things, but I guess I will find out!
Thanks for stopping by, Andy. Glad this was helpful. You gave me a good idea for a future video.
YT algorithm seems to find these great tubers..
Thanks!
Great video Keith and very good speaker. 😀
Thanks Roy!
I plan to use a VFD to drive an old 3 phase induction motor on single phase power on a bridgeport mill. This older motor was made in 1987 with E class insulation. A grounding ring would be half the cost of a new motor. Would you recommend just running this one till it dies and then replacing with an inverter rated motor? How long would you expect something like this to run before it dies? Would you expect weeks/months, or would it be more like a few years? Not going to hold you to anything of course, just curious roughly how long you think a motor like this would last in my situation.
Thanks for the question. Running it till it's dead and then replacing with an inverter rated motor is not the worst idea. A shaft grounding ring is not the magic bullet solution to make a non-inverter-rated motor run on an inverter so it's recommended to buy an inverter duty motor. As for life span, due to a lack of standardization for older motors, it's nearly impossible to tell. Some will run smooth for years while others start chugging in weeks. Though from the limited Bridgeport inquiries I've dealt with, they have usually ended up lasting on the order of months.
I hope this helps! Happy tinkering.
- Keith
We had well over a 100 plain Jane non VFD rated NEMA motors that were installed in the 1970's from 3 to 250 HP that were changed over to drives over 25 years ago. Lucky if we had two old motors a year burn out. Most did have line reactors. Most ran under 90% of rated RPM .
Thanks for the comment.
Older motors are a bit of an enigma when it comes to VFD rating. A lot of them were manufactured to a very high standard of workmanship and incorporated insulation/magnet wire that would allow for safe operation under a VFD with sufficient thermal headroom for turndown but at the same time you have plenty of motors that weren't. The nice thing about purpose-built/tested inverter duty motors is the guaranty of safe operation under inverter power. A non-VFD-rated motor would likely have more to gain from a load reactor than a line reactor.
Thanks for the great information. Would MFR-J55WZ0BP-0114 be an okay candidate to control with a VFD? Planning to update my drill press to support low end RPM for punching holes in metal. I can't find the data sheet but there are lots of images of the motor ID plate. Kind regards.
Thanks for the question Rusty! Based on the catalogue number, you are working with a DC motor. To control a DC motor, you'll use a DC drive. VFDs are used on AC motors. Here's an overview of our DC drives available in Canada and the US: www.emotorsdirect.ca/controls/dc-drives
@@emotorsdirect Thanks. Any recommendations for a controller?
@@rustyshackleford9066 For sure - your options will depend on where you're located. Do you mind sharing that? Thank you
GTA Ontario. Thanks @@emotorsdirect
@@rustyshackleford9066 the KB Electronics KBWT-112 would be a good solution for low end torque: www.emotorsdirect.ca/item/kb-electronics-kbwt-112. However, before buying I would first check if this motor has a drive built in. One of my coworkers is a VFD specialist (Ahsan). If you give him a call, he can help you confirm if the motor has a drive built in. He can be reached at 1-800-890-7593 ex 108 and I shared your project details with him.
Can We use Continuous (S1) Duty motor for VFD operation ? We are taking S1 motors with insulated bearing and class F insulation. Both motor and VFD are new.
Great question. All industrial motors built in the last 10-15 years would be VFD rated, you would just need to verify the motor turndown is in the range that you are going to use. Some motors only come with 2:1, 4:1, or 10:1 turndown and you may want to go slower than that.
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Lucky to have watched this Video. Insights, insights and insights.
Thanks Kuong!
Very good information, Thank you.
Thanks Pravin!
It's a little hard to tell from the video, but is the main problem with using a VFD that it is not as clean or smooth as true 3 phase? I am thinking of a very narrow application where you would simply want to run 3 phase from a single phase. For instance, if you bought an industrial compressor on the cheap and wanted to use it at home. The VFD would essentially just be a way to use the 3 phase motor on a residential single phase supply. It would be configured once and never change. In this scenario does the VFD negatively effect the motor, or have the potential too? I'm trying to understand if the issues raised in the video are due to the assumption that the VFD will be used to actually vary the motor speed or not. In the scenario I described the VFD would be more like a fancy starter.
Hi Travis, thanks for the question. Due to the way that VFDs reconstruct the power waveform they produce large voltage spikes, these spikes can overwhelm the winding insulation, short them out, and start arcing. The arcs produce heat that further damage/degrade the windings. A similar phenomenon may happen across the bearings. Most manufacturers now use inverter grade magnet wire as standard and this neutralizes the winding arcs. Bearing discharge remains a problem but you can always get a grounding ring.
A further consideration is that VFDs are so much cheaper than running a 3 phase line or a rotary converter that you could burn out and replace your existing motor with an inverter grade motor and still have saved money compared to the other options.
@@emotorsdirect Thank you very much for the reply. That clears up my confusion.
Happy to help @@travisthompson1679 ! That's what I'm here for.
Golden information thanks 😊
Glad this was helpful!
Great commentary - thank you. It's great to have such direct presentation.
I thought the remarks about fan speed/cooling to be advice that comes from genuine broad expertise about function and life cycle and particularly insightful.
I'm curious and would welcome your advice on a matter you cover here.
Is conductive grease used to mitigate the potential difference between the armature and motor body? I presume the problem is that the grease isolates the armature from the main body and grounding setup, so becomes a source of heat and grease degrades?
I ask this as I am looking at ways to diminish precipitation static in a coffee grinder design where the motor mounts one grinding face and the body of the grinder the other. The bearings are an isolating factor. As coffee is ground static charge accumulation occurs due to the friction.
I had thought the use of conductive grease in the bearings would ensure the armature could be grounded more uniformly and reduce static in the ground coffee by dissipating it as it generates.
You may not be an expert on coffee but I hope you may have some insights into the ground loop and contribution of the bearings and their conductivity on it in a motor :).
Hi Michael, thanks for your comment. This is the point of conductive grease. Alternatively, grounding rings would also do the same thing. Check out my video on grounding rings for more specifics: th-cam.com/video/olqO0cRvPeI/w-d-xo.htmlsi=xt1VyrcLpSxyzJ4U
@@emotorsdirect Thank you sir. I'll go watch the video you linked :).
Have you perchance done any videos on dissipation of precipitation static (P-static) on a single or multi-ground system?
@@michaelrobinson9643 I haven't done a video on this but thank you for the suggestion. Stay tuned for new episodes coming next month, focused on VFDs.
Thank you for this video! I can tell you have a huge knowledge base to draw from. I run an residential HVAC company and I'm getting a bit tired of replacing inverters that are 4500$ our cost due to proprietary software and communication. I feel like it shouldn't be terribly hard to build a system that can use more standard a more standard VFD and maybe simplify everything a bit. One issue I'm running into is that most of this info is directed more to 3 phase input industrial applications. All of our residential service only allows for 240v Single phase. My dream is to build something similar to the Bosch condenser that ramps up and down dependent on refrigerant pressures and doesn't need direct communication with the indoor unit past the signal to turn on and off; but do it with readily available VFDs like industrial Legos. Would you have any advice on what I need to look for in a compatible VFD and Compressor with my single phase limitation?
Hi Scott, thanks for the comment! Wow that's steep - where are you located?
The SINUS M series of drives would be perfect for this application. Any of the three phase drives we list, if sized correctly, would also work for a single phase application. Contact our tech team for more support there if needed: www.emotorsdirect.ca/contact-us
FYI - we have a few single phase specific videos coming this year - hopefully you'll enjoy those.
- Keith
Hi Keith! Please support on this: I have a mini lathe with variable RPM (Paulimot 190-V), just bought it, brand new. Right after pressing the Start button, but BEFORE the motor starts spinning, a high frequency sound appears (10k Hz) and keeps sounding no matter the RPM is, until the lathe stops. Could this be the VFD? How could I diagnose it better? Thx!
Hi Sorin, thanks for the comment. Yes, that is sound of the VFD output's switching frequency. There is really no fix for this outside of isolating the VFD in a box to reduce how much sound gets out.
Very nice thank you for the information.
Thanks for the comment!
Hello. I have a Romanian SP81sw bench lathe, it's small with an 80mm universal and it has a 0.37 kw / 380v motor. I only have a 220v network. What power should the VDF have for this motor, should I switch it to a VFD to run on 220v .Thank you!
Hi Lacovache, Based on your network voltage, you should go with a 220v motor and a 220v VFD. The voltage delta is too great.
VFD's Can also be used to create 3 phase supply for motors from a single phase input.
This comes in handy when you have single phase input (common in residential and some commercial applications). Check out the video I just created on this subject: th-cam.com/video/skEaxx5YJbI/w-d-xo.htmlsi=QHBAtly4EbqMlSWI
How do you regulate the much current being drawn by a motor let me say for a motor of about 250kw when using a vfd
Hi Tigalana, thank you for the question. A VFD cannot control how much current a motor draws. Without going into detail, a motor will draw as many amps as it needs in order to turn the load. Under normal running conditions the amp draw is a function of the torque required which often scales proportionally with RPM. The only way I can see a VFD controlling current output is via speed control. VFDs often include current limiting circuits and thermal overloads. So they can stop the motor if amperage exceeds a set amount.
I hope this helps!
Would this video be helpful in knowing if you can use pulse width modulation with a motor?
I think its an analogous situation.
New to electronics, please help
Hi Joseph, here's another one of my videos that covers PWM: th-cam.com/video/UWsy-O-0XfM/w-d-xo.htmlfeature=shared&t=226
@@emotorsdirecthi emotors direct, this is quite useful for me because I know see that vfd's utilize pwm themselves.
Thank you
@@josephdaquila2479 Glad to hear it! Releasing a few more VFD videos in the next few weeks. Stay tuned!
I have a spare 2hp 3ph I want to use but can't find any info on it. The part number is "US Motors p63fte-1793" and I'd like to find the right vfd. Any recommendations?
Hi Scott, did some digging and it looks like this is a TEFC class B insulation motor. Some things to keep in mind:
(1) Duty: fan-cooled motors will have cooling issues when slowed, however, the thermal mass of the motor can hold some heat before getting too hot so intermittent use can offset the thermal load.
(2) Insulation: though insulation class is a purely thermal standard, it just so happens that when motor manufacturers put in better thermal insulation, they also put in better electrical insulation, so we generally recommend class F and up. Many class B motors will also run fine on a VFD, but it will likely take a toll on some of the mechanical components.
(3) Required turndown: since you're considering VSD operation, I'm assuming you want some degree of turndown, but it makes a huge difference for operation if you want a 1:4 turndown vs 1:10 for example.
I would say any of our lower-cost VFDs (ex. L510-202-H3-U) would work depending on how often it will be used and the degree of turndown. If you're working with a single-phase supply, go with a TECO Sinus M.
This is an off-label application and thus performance and longevity are very application dependant. Your motor may develop a wabble over time, in which case, you could replace that spare motor for a few hundred dollars.
Thanks for the comment!
@eMotors Direct Thanks. The motor will be used extremely intermittently, like 5 minutes on and 30 minutes off. And even then, only a few times each day. This is not for a continuous use application. I'll likely only be slowing it to around half speed, maybe a little less, when I do slow it down, and that won't be often.
I suppose I could have included all of that in the beginning, but then I may have missed out on some of the info you just shared. Thanks again!
@@Chromevulcan Awesome, good luck with your VFD Scott!
thank you for this insight. my question, is there a way to use a VFD with single phase induction motor 4 poles that uses a centrifugal clutch? i mean, is there a way around it?
Great question. Technically you can. There are TH-cam videos out there that show how to do this. But it's not something we recommend as VFDs and single-phase motors were not designed to be used together in this fashion. It could burn the motor out or it could damage the VFD.
@@emotorsdirect thank you for your reply, i was looking for a VFD to add to my drill press motor, but might be better off with a 3 phase motor first , thanks 👍
@@NLDHGRockStaR 100%. Let us know if you need a hand finding the right motor or controller.
@@emotorsdirect will do, thanks 👌
Very helpful, thank you!
Thanks Bruce
Sir, can you please tell me, what kind of vfd compatible motor can be used for irrigation/agriculture area for pumping the water ?
For pump applications, I usually recommend the TECO F510 series or WEG CFW 500 series:
www.emotorsdirect.ca/search?keywords=cfw500
Great work , thx alot .
Glad you liked it!
Thanks Sir
Please i need your help
We have 3ph Siemens ex motor 1mj7 310-2cc60-z with 95.7 kw
My question could we drive this motor with a vfd or its not supported ?
Hi Basrawwi, thank you for the comment. Most motors built within the last 15 or so years will operate fine on a VFD as higher insulation classes and inverter grade magnet wire are standard practice among higher end manufacturers in the industrial space. The problem here is that I don't see an explicit rating for this particular motor, so its impossible to say how much turndown the drive can handle. Typically at this point, I'd reach out to the manufacturer of the motor to confirm. Siemens may be able to answer this question for you with more certainty if you reach out directly. Siemens recently sold their low voltage line to ABB, so they may also be able to help you out.
@@emotorsdirect
Thanks alot Sir, really appreciate your help.
actually i tried to get confirmation from Siemens 3 days ago, but i didn't get it yet, may be i need to send them a reminder.
Thanks a lot again...
Hello sir this video is very informative. I have some question. How can identify the vfd for a direct drive motor below .5HP motor 140RPM thank you for the help.
Thanks for the comment! We'd need more information on the motor to recommend a VFD. If you answer the questions on this form, I can make a recommendation: www.emotorsdirect.ca/request-quote
your thoughts on vfd on older J head Bridgeport mill motor?
These old mechanical variable gearbox motors are non-standard and very old. A VFD would probably work but it's uncertain how long. Since these motors are likely difficult to replace I wouldn't recommend it. You could bypass the J head varidrive entirely and throw in a newer motor however I'd need more details on the project to be sure.
I want to connect 6 X 260kw motors on a single 2000kw vfd. Which brand of vfd would you recommend.
Thanks for the question. Whether any brand would offer a 2000 HP VFD would depend on input voltage. If you want to individually speed control the motors, you will need to use one VFD per motor. If you want to speed control 6 motors on an individual level from a single interface, you will need 6 drives in a master/slave topology with a single drive playing the role of master and controlling the other 5.
The only series of drives in our LV(230V-600v) catalogue that WILL DO 2000kw is the cfw11 series: www.emotorsdirect.ca/search?keywords=cfw11
For a 10hp pump which corresponds to 7.5kW, do I use a 7.5kW vfd or slightly above that? Thank you
Hi Anas, thanks for the question. VFDs are sized by current. Manufacturers will generally add a horsepower rating with a decent safety factor. Check the FLA on the motor and the rated output current. If the latter is the greater of the two you're doing great.
How would I know if a motor is of a SRM type? WOuld I need a special VFD for such motors?
SRM motors will generally be labelled on the nameplate. They require specialized drives to function.
I really hope you can answer this question: I want to make my home AC condenser compressor variable speed with a VFD. It’s a single phase 220V 1.75 ton 21kBTU compressor so about 2hp. RPM of a residential scroll compressor is about 3,000. I want to vary it to about half. You think I could make it work?
You could make it work if replacing the motor.
Compressor and motor in same unit.
Can I use a vfd with a synchronus servo motor, ignoring the encoder feedback?
Yes, as long as the drive is rated for the underlying motor type.
If you run the motor at too high speed, its torque can decrease to the point when it can't maintain rotation and will straight up stop completely, coils will draw too much current and damage VFD and themselves, potentially causing fire.
Also if you run it at really extreme speed, and this motor is large, its rotor can just tear itself apart, causing massive destruction to whatever rotor's debris hit.
Thanks for your comments. Here's a video on how fast you should run your motor and why: th-cam.com/video/skEaxx5YJbI/w-d-xo.html
I have a late 60s 2 speed motor that has been swapped to a drive. When slowing in an unloaded direction (possibly reverse loaded for slowing down with a regen resistor) it chatters and hiccups some runs. I believe the motor is high slip but low info on the data tag. Also possibly a gear box problem. Any suggestions? Thanks for your video.
Hi Rob, this is highly dependent on the type of two speed motor and how the speeds are selected. In order to diagnose a high slip situation, I recommend watching the output current. The magnitude of slip is proportional to torque and thus the output current.
Hello Sir ... I have a concern. My plant has a lot of fluctuating load. The main substation has a lot of fluctuation in amperes. Which we see in the ampere meter. How can we reduce this falctuation load?
Good day.i have an home appliance from europe which power supply is 220v 50Hz.what can i do so that i can use it in my country,without damaging the motor, where our power supply is 220v but 60Hz.thank you in advance and more power.
Hi Jonathan, thanks for the question. You can use a VFD to operate at a higher or lower frequency, but there are some limits. In your case, this should work fine.
Thanks for your expertise. Is it possible to use a VFD on single phase motors. I am setting up an off grid wood machining shop and am trying to size an appropriate generator and hoping to reduce inrush current so I do not need an oversize generator. Any advice would be appreciated. I am going single phase as my existing machines (biggest 5hp) are single phase and because of the wide range of single phase tools available . It will also be used as the backup generator for a solar power system.
I would recommend running a three-phase motor as single phase output VFDs can be expensive and most modern 3 phase VFDs can't run a single phase load due to phase-imbalance-trip circuitry being standard. As for the intuition on not needing to oversize the generator, you are correct that the VFD would reduce inrush. But on the converse, you'd still have to oversize the generator for the harmonic distortion the VFD would produce unless you paired it with line filtering. If you'd like the particulars on any of this, please email us and we can help iron out the full package of things you would need in either scenario.
I have a question for you. I have standard 110 in my garage and I have a 3 phase motor I want to use on an old drill press. The motor is manufactured by “Brown & Sharpe and its 3 phase Alternating current. There are nine, all painted black, wires protruding from the motor. Three sets of two have been twisted together and there are three left alone. Their numbers are 1, 2 & 3.
The motors information plate on the exterior of the motor shows that it can be wired 208-220 or 440. Under the 208-220 it shows the following:
3 lead motor 1-2-3
6 lead motor 1-2-3
6-4-5
9 lead motor 1-2-3
7-8-9
4-5-6
So, can my motor support the use of a VFD and if so how do I wire it???
Is my motor VFD compatible? If so, how do I wire it???
Unless the nameplate has some reference to VFD or inverter rating, it is unlikely the motor is rated for VFD use. However, some non-rated motors just happen to be built with inverter grade magnet wire and can function just fine under inverter power with the carrier frequency set low. Unless the motor is somehow uniquely valuable, throwing a VFD on it will restore operation. But this might burn out the motor.
A lot of motors made these days are VFD rated, but since it's an older drill press, it's hard to say.
Most VFDs will come with a wiring diagram that will walk you though how to hook up the motor.
Very useful information Thank you
Glad it was helpful!
Can I run a vid on a Leeson 131534.00 it’s for 2007 but it’s barley been used than in advance
Hi Jay, thanks for your question. Some single phases motors can be run on a VFD when sized appropriately. However, cap start induction motors like the Leeson 131534.00 cannot, the motor starts on a capacitor and has a switch that bypasses the capacitor at around 80% RPM. This means that if you under-speed it past about 80% the capacitor is brought into the circuit and since the capacitor isn’t rated for continuous operation it will burn out.
Hey you did a good explanation
Thanks Ernest!
When the motor is direct started without VFD. It is protected with a motor circuit breaker.
When using VFD, how do we protect the motor?
VFDs have overloads built into them and will fault out when too much current flows. It's not recommended to use an overload/contactor on the output of a VFD. Thanks for the question!
Yes always use safety glasses when dealing with electrons
Like your videos and my question is if this model of motor works with vfd. Model #5k49nn4472x thanks
I couldn't find much information on this motor. I'm assuming this is a discontinued OEM motor. Because it looks older and is ODP, I'm guessing it's not rated for VFD use. It may not have the cooling capacity required to use with a VFD.
Question: if the VFD 1.5 KW it can work to 8 KW HVAC?
First time to install the vfd 1.5kw and hvac 8kw
You can consider 'horsepower' and 'kilowatts' synonymous in this video. You should size your VFD based on the motor FLA and voltage, not the horsepower (or kilowatts). But generally speaking, we can match motor horsepower to VFD horsepower (ie. 8 HP motor to 8 HP VFD), unless you have an application with a high degree of overload, in which case, you should oversize the VFD.
Based on the information, I think your VFD is probably undersized for your motor.
Unusual, most high capacity electrolytic capacitors in circuit have bleeder resistors across their contacts to bleed off high voltage.
They do have bleed circuits. If this is about letting a drive rest a bit before opening it up to inspect it, the prohibition regarding rest time is to allow the bleed circuit to reduce the stored charge to safe levels.
I have a b a l d o r brand motor it requires vfd the motor is three-phase and it's 200 to 400 volts on the ID tag the question that I have is it powered by 120 volts ac to the vfd to control the motor or does it still need to be hooked to 220 can't seem to figure this part out
Hey Tony, thanks for the question.
This will depend on the rating of the VFD.
Take this example of this KB drive (www.emotorsdirect.ca/item/kb-electronics-kbda-27d), it is rated for either 115V or 230V input but will always provide a 230V output since it has a voltage doubler for the 115V line. For a drive like this, it can take 115V input and output three phase 230V for a 230 V motor. If your drive doesn't include a voltage doubler, then you will need to provide a 230VB input.
I hope that answers your question. - Keith
Can VFDs be used for 3 phase induction motors ?
Yes
I'm electrical stupid..
I have a 110 V 3 H.P. 3 phase motor.
I want to run it on a regular home single phase system. So I think I need a 110 single phase input, to 110 3 phase output VFD.....are they available... can I do this setup ???
Hi Roger, thanks for the question.
3HP is too large a motor to run on 120 single phase assuming 100% efficiency. A 3HP motor would need 19 amps and most home breakers will be 12 or 15 amp The wiring will be matched to the breaker size. If you are okay with using current limiting on their VFD to effectively turn the motor into a 1.5HP motor then this can work.
120V->120V VFDs don't exist. Most 120V VFDs output 230V through a doubler circuit.
Let me know if you have any follow up questions!
Can a vfd be safely used on an old Baldor 3 ph 3 hp unisaw motor? I only want to run at 3450 rpm and use my 1 ph power source.
Doable, however this will likely reduce the life of the motor if the insulation/magnet wire is not up to snuff. I would need to see the nameplate to provide concrete advice.
What about mod t55 cxbwe for vid?
I'm not familiar with that motor. Although I noticed that model number is used for a specific tank. That's outside of my wheel house.
What about mod t55 cxbwe for vfd
I'm not familiar with that motor. Although I noticed that model number is used for a specific tank. That's outside of my wheel house.
What about three phase ?
Good question - a lot of three phase motors can be used with VFDs but not all three phase motors are inverter rated.
@@emotorsdirect
I have a seventy year old Delta wound motor. Mortising machine. Heavy duty cast iron frame. Heavy duty bearings. Will it cope with a VFD ? 4 hp , 2850 rpm, .5 hour rating. Is Delta wound less suitable for VFD? It doesn't have a junction box to change to star Delta.
Can the VFD be used on three phase induction motors ?
Who you please share your email for more consultations? I will greatly appreciate it 🙏
Hi Alex, thanks for the comment! Yes, generally speaking, VFDs can be used with three phase motors. Where are you located? I can point you in the right direction from there.
Vfd for cnc
Thankyou sir
Hello sir
Your explanation and , you speak too fast,
The listeners don't understand
I'll say, talk slow so that we understand
Hi Rodolfo, Thanks for the tip. You can use the little gear icon and then click 'playback speed' to slow down the speed of the video - I hope that's helpful.