VFD 110V-110V parameters setting

[mactec54]

While I take everything from mac with a heaping of salt , I don't discount that he has a valuable perspective. It may be one which appears to be skewed by experience, but since I have experience only with a high spec world and he's been dealing with the full gambit, I wouldn't discount it at all.

Do I think he's rude and fails to actually back up his claims with anything beyond hand waiving? Sure. That doesn't mean he hasn't seen what he's seen. I encounter other engineers (myself being an ME/EE mostly from Automotive startups and servo motors) all the time who have tremendously valuable experience and totally wrong interpretations about root cause. Correlation and causality are not at all the same, but it's so easy to conflate. I've spent almost half of my career hunting down causality rather than correlation and dang is it a tough thing to do.

So just to summarize, don't necessarily take everything from mac as gospel, but don't dare discount the experience. Whether or not he's attributing causality correctly or not, I have yet to form an opinion in any particular case. I do believe he's not lying about correlation.

That means: Underrated drives fail when paired with higher motor ratings is likely true. The WHY is not yet determined imho. I believe it's due to drive design shortcuts in low quality drives and/or user error (VERY LIKELY AT LEAST SOME USER ERROR ALWAYS). I don't know what the cause is. I have in my mind and have posted my suspicions, but each drive failure case would be it's own investigation.

You can contact or call any VFD Drive manufacture they will tell you the same thing, this is not something I came up with and it is something you should already know, with your doubting posts makes you look like you have not had very much VFD Drive experience

User Error about 10% but 90% for undersized VFD Drives being used

When using Single Phase all manufacturer's will recommend a larger capacity VFD Drive than the motor / spindle normally 1Hp to 2Hp larger, ( Simple Math will tell you this ) if the VFD Drive is Rated for Single Phase use then it's input electronics' have a higher rating and can handle the extra current needed for Single Phase use, most VFD Drives though are not rated for Single Phase so this is where the problem is with 3Ph VFD Drives , the input Electronics are rated for there intended purpose and not double the Amps required for Single Phase use

[StrawberryBoi]

I have yet to argue against derating a drive under 1ph inputs. I am merely asking for you to justify the claim that the drive will fail when driving a motor with a higher nameplate (but with appropriate parameter settings in the VFD) with a cause to that failure beyond a mismatch of semi-arbitrary nameplate values.

https://www.controleng.com/articles/...-and-failures/

Derate it appropriately, use correct parameters. I've reached out to Yaskawa and will reach out to two other VFD manufacturers for an inquiry, however all documented concerns I can find are related to damaging the motor though an overrated drive running with inappropriate parameters for the motor, not the other way around. I have even found a number of references (anecdotal) to a 'common' practice of using a lower rating on the paired VFD to prevent motor overheating. Until I get word back from the suppliers I'll keep my doubts in hand.

[StrawberryBoi]

WEG guy is working late it seems. I got a call (reminding me not to put my phone number in late night e-mails if I don't want random sales calls at all hours). The WEG regional rep says that for a single input drive, driving a motor of same or lower voltage rating within it's service frequency range, undersizing the drive by as much as 50% is totally fine and not unusual at all. Their CM300 line is able to self protect and regulate current within that range. He told me that similarly, oversizing the drive a little is fine, but dramatic mismatch is a definite issue.

He did tell me that even their own drives as recently as just 5 years ago needed to be sized much more closely, but they've completely phased out the older control chips and algorithms. Additionally this is a spindle operation so inertia at startup is very small and the overload condition exists for just a second or so. He told me that WEG, Hitachi, Yaskawa and all other major name suppliers will have similar ratings and recommendations as they don't vary much from each other.

That said, I dug through a pile of disorganized and nigh unsearchable pages from Yaskawa until I found a definite reference to "...motor must be rated lower than the drive...". This requirement was referring specifically and exclusively to using their three phase drives that are NOT 1ph input rated with a 1ph input. In their documents regarding their specifically 1ph rated drives (all of which are 1ph/3ph that I could find), there is no such restriction stated (EDIT: That I could find). The limit is really that they can only manage overload currents down to about 25% of the drive rating and up to 150% of the drive rating, with a 1 minute rating (on at least the economy targeted stuff). WEG also uses a 1 minute rating. If you are using an undersized drive, then you need to make sure that the drive is capable of supplying within the rated operating ranges for the motor being driven. Just meaning, for example, that if the spindle motor is rated for 6,000-25,000rpm, you don't pick a drive that can't achieve 6,000rpm.


Again, summary, for older designs I was told closely match the drive and motor, for 3ph input units being operated with 1ph input, derate and oversize the drive.

Oh, and Yaskawa on the 3ph used as 1ph says they will require a DC link choke. For the 1ph/3ph drives they specify either a choke or a 3% line reactor, but it's dependent on the drive/motor combination, cable length, etc. They recommend the DC link choke almost for almost all situations and big drives have one internally.

I begged off with the WEG guy cause it's bedtime for me, I didn't get into that deeply. I need a vfd/inverter for an industrial motor contract anyways, so I'll be e-mailing the guy over the next few weeks anyways.

[mactec54]

WEG guy is working late it seems. I got a call (reminding me not to put my phone number in late night e-mails if I don't want random sales calls at all hours). The WEG regional rep says that for a single input drive, driving a motor of same or lower voltage rating within it's service frequency range, undersizing the drive by as much as 50% is totally fine and not unusual at all. Their CM300 line is able to self protect and regulate current within that range. He told me that similarly, oversizing the drive a little is fine, but dramatic mismatch is a definite issue.

He did tell me that even their own drives as recently as just 5 years ago needed to be sized much more closely, but they've completely phased out the older control chips and algorithms. Additionally this is a spindle operation so inertia at startup is very small and the overload condition exists for just a second or so. He told me that WEG, Hitachi, Yaskawa and all other major name suppliers will have similar ratings and recommendations as they don't vary much from each other.

That said, I dug through a pile of disorganized and nigh unsearchable pages from Yaskawa until I found a definite reference to "...motor must be rated lower than the drive...". This requirement was referring specifically and exclusively to using their three phase drives that are NOT 1ph input rated with a 1ph input. In their documents regarding their specifically 1ph rated drives (all of which are 1ph/3ph that I could find), there is no such restriction stated (EDIT: That I could find). The limit is really that they can only manage overload currents down to about 25% of the drive rating and up to 150% of the drive rating, with a 1 minute rating (on at least the economy targeted stuff). WEG also uses a 1 minute rating. If you are using an undersized drive, then you need to make sure that the drive is capable of supplying within the rated operating ranges for the motor being driven. Just meaning, for example, that if the spindle motor is rated for 6,000-25,000rpm, you don't pick a drive that can't achieve 6,000rpm.


Again, summary, for older designs I was told closely match the drive and motor, for 3ph input units being operated with 1ph input, derate and oversize the drive.

Oh, and Yaskawa on the 3ph used as 1ph says they will require a DC link choke. For the 1ph/3ph drives they specify either a choke or a 3% line reactor, but it's dependent on the drive/motor combination, cable length, etc. They recommend the DC link choke almost for almost all situations and big drives have one internally.

I begged off with the WEG guy cause it's bedtime for me, I didn't get into that deeply. I need a vfd/inverter for an industrial motor contract anyways, so I'll be e-mailing the guy over the next few weeks anyways.

Again you are talking BS I install and sell Yaskawa Drives, what you are posting, is just a repeat of some of what I have already posted, but you manage to fill pages with zero information that would help anyone

So the WEG Sales person called you give me his contact number He won't mind if you post it here, just remember you where talking to a Sales person not a Tec support person

[mactec54]

https://www.controleng.com/articles/...-and-failures/

This link you posted says the same as what I have been posting I guess you still don't get it

They are only using a derating of the output Amps to protect the input, for Single Phase use, which is the same as what I have been posting

What I have been saying is the Input rating of the Drive has to be double the output, which is the same thing as what they are saying to the derating the output

[StrawberryBoi]

This link you posted says the same as what I have been posting I guess you still don't get it

They are only using a derating of the output Amps to protect the input, for Single Phase use, which is the same as what I have been posting

What I have been saying is the Input rating of the Drive has to be double the output, which is the same thing as what they are saying to the derating the output

Yes, but the part of the conversation you are ignoring is the part where you hand-waive about the output rating vs motor rating. The input derate is not being discounted by myself or even really, by the OP.

You are making an incomplete statement with, I believe at this point, purely the intent to try and make people feel stupid. I will continue fact finding, please provide facts or troll somewhere else. Real and complete information is valuable.

[mactec54]

Yes, but the part of the conversation you are ignoring is the part where you hand-waive about the output rating vs motor rating. The input derate is not being discounted by myself or even really, by the OP.

You are making an incomplete statement with, I believe at this point, purely the intent to try and make people feel stupid. I will continue fact finding, please provide facts or troll somewhere else. Real and complete information is valuable.

"Real and complete information is valuable" then please provide some instead of your arm chair comments, that have no substance at all

Here is a new Hitachi VFD Drive specs this VFD Drive would fail being used for 240v Single Phase with a 1.5Kw Motor /spindle as the input currant rating is not high enough to support what this motor requires this is as simple as it gets, yes you can dumb down the VFD Drive but then what would be the point of trying to run a then wimpy 1.5Kw motor

[StrawberryBoi]

"Real and complete information is valuable" then please provide some instead of your arm chair comments, that have no substance at all

Here is a new Hitachi VFD Drive specs this VFD Drive would fail being used for 240v Single Phase with a 1.5Kw Motor /spindle as the input currant rating is not high enough to support what this motor requires this is as simple as it gets, yes you can dumb down the VFD Drive but then what would be the point of trying to run a then wimpy 1.5Kw motor

Whether or not the motor is wimpy is in the eye of the user and their application. The debate has centered around whether or not using the lower rated VFD with a higher rated spindle motor would damage the drive, not whether or not it was going to be sufficient mechanical power.

[XYZGnomon]

Whether or not the motor is wimpy is in the eye of the user and their application. The debate has centered around whether or not using the lower rated VFD with a higher rated spindle motor would damage the drive, not whether or not it was going to be sufficient mechanical power.

For the record, I am not concerned about damaging a $200 drive. I just magically destroyed a slightly more expensive drive and I'm not crying about it.

I want to make parts in my home shop, and I have power limitations and neighbors within earshot; if that means I burn out a little appliance every now and then, well... then that's the CODB.

I just ordered some capacitors from Digikey, and I'm fairly confident that as soon as I zip the KB drive back together it will serve as a backup in case I break the rules and my WEG drive complains.

[mactec54]

For the record, I am not concerned about damaging a $200 drive. I just magically destroyed a slightly more expensive drive and I'm not crying about it.

I want to make parts in my home shop, and I have power limitations and neighbors within earshot; if that means I burn out a little appliance every now and then, well... then that's the CODB.

I just ordered some capacitors from Digikey, and I'm fairly confident that as soon as I zip the KB drive back together it will serve as a backup in case I break the rules and my WEG drive complains.

You Won't have any problems with the WEG it is designed to run on your 120v supply, you may still get some Breaker tripping if the cuts get to heavy, your main problem will be your neighbors if they are really close, as the VFD Drive will interfere with there TV Etc, so wiring is key and an EMI Power Filter in the right place, and you won't have any problems with electrical noise

[mactec54]

Whether or not the motor is wimpy is in the eye of the user and their application. The debate has centered around whether or not using the lower rated VFD with a higher rated spindle motor would damage the drive, not whether or not it was going to be sufficient mechanical power.

In most cases you can stop the motor with your hand, if that is not wimpy, it is totally useless, when these guys are cutting aluminum or anything with there machines they don't want a wimpy spindle

I put up a $1000.00 says it will damage the VFD Drive over time it won't happen straight away, but will happen

[XYZGnomon]

You Won't have any problems with the WEG it is designed to run on your 120v supply, you may still get some Breaker tripping if the cuts get to heavy, your main problem will be your neighbors if they are really close, as the VFD Drive will interfere with there TV Etc, so wiring is key and an EMI Power Filter in the right place, and you won't have any problems with electrical noise

mactec54:

If you want to be taken seriously as a subject matter expert, you can't post run on sentences like this. It has the same practical effect as writing it out in crayon on a chalkboard; the substance of your argument is lost in the absurdity of it. And that doesn't even take into consideration that punctuation allows to you separate key points of your argument, or present them in a logical order. A run on sentence does the exact opposite.

[mactec54]

mactec54:

If you want to be taken seriously as a subject matter expert, you can't post run on sentences like this. It has the same practical effect as writing it out in crayon on a chalkboard; the substance of your argument is lost in the absurdity of it. And that doesn't even take into consideration that punctuation allows to you separate key points of your argument, or present them in a logical order. A run on sentence does the exact opposite.

Well if you can't understand what I Post, because of the lack of punctuation, I think you have a bigger problem

[XYZGnomon]

Well if you can't understand what I Post, because of the lack of punctuation, I think you have a bigger problem

Don't shoot the messenger.

[mactec54]

Don't shoot the messenger.

You are using this phrase out of context, as you are not the messenger and not likely to ever be

Understand what you are posting, before you post it, then others won't have to waste, there time to reply to your ridiculous posts

"Shooting the messenger" is a metaphoric phrase used to describe the act of blaming the bearer of bad news

[XYZGnomon]

You are using this phrase out of context, as you are not the messenger and not likely to ever be

Understand what you are posting, before you post it, then others won't have to waste, there time to reply to your ridiculous posts

"Shooting the messenger" is a metaphoric phrase used to describe the act of blaming the bearer of bad news

If you are unable or unwilling to believe that grammar and punctuation are important for communication, and unable or unwilling to accept constructive criticism, what are you doing here?

You have injected yourself into this discussion for some reason, and I have ignored almost everything you've said because it's gibberish. Learn how to construct a sentence and communicate your ideas logically.

I sincerely apologize for everyone else in your life if no one has tried to have this conversation with you before.

[mactec54]

If you are unable or unwilling to believe that grammar and punctuation are important for communication, and unable or unwilling to accept constructive criticism, what are you doing here?

"That's is petty at best"

You have injected yourself into this discussion for some reason, and I have ignored almost everything you've said because it's gibberish. Learn how to construct a sentence and communicate your ideas logically.

"Then ignore your choice" Sorry if you could not understand what I posted, it is obvious above what you are able to comprehend you are making yourself look more ridiculous, with every post you make.

I sincerely apologize for everyone else in your life if no one has tried to have this conversation with you before.

Everyone around me have PHD's and Masters Degrees, have no problem with my conversations, or any other type of communication

"Next time you want to post about something, start your own Thread, instead of messing up the thread someone else started "

[XYZGnomon]

"That's is petty at best"



"Then ignore your choice" Sorry if you could not understand what I posted, it is obvious above what you are able to comprehend you are making yourself look more ridiculous, with every post you make.



Everyone around me have PHD's and Masters Degrees, have no problem with my conversations, or any other type of communication

"Next time you want to post about something, start your own Thread, instead of messing up the thread someone else started "

I tried. This EXACT same conversation with my brother went EXACTLY the same way.

Maybe that's why I care. I sincerely want to help you, but I have absolutely no skin in this game. All of those people in your life with advanced degrees and they've never said a word about your grammar? Either you're hiding something or they're afraid of confrontation. I don't have that problem.

Please don't shoot the messenger. Run on sentences, especially in a technical conversation between subject matter experts, is unprofessional.

[mactec54]

I tried. This EXACT same conversation with my brother went EXACTLY the same way.

Maybe that's why I care. I sincerely want to help you, but I have absolutely no skin in this game. All of those people in your life with advanced degrees and they've never said a word about your grammar? Either you're hiding something or they're afraid of confrontation. I don't have that problem.

Please don't shoot the messenger. Run on sentences, especially in a technical conversation between subject matter experts, is unprofessional.

I guess your are the expert, that could not even read a simple VFD Drive manual and poof the magic happened

I guess you mean well, your brother was aware of what was coming next.

No more time to waste on this, as it is not helping others that need the help, you don't need any help as you have, StrawberryBoi and Jim, they will work there way though, what ever you need

[chromvis]

Sorry to revitalize this thread, but it is the only one I found that discussed the possibility to use lower rated VFD with higher rated motor. I have exactly this need. I have 6040 CNC with 1.5 kW water cooled spindle motor rated for 110 V. It is more than sufficient for my needs, but it has ER11 collet which is very inconvenient. I also have 2.2 kW water cooled motor rated for 110V (https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1) which I run using the following VFD (https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1) without any problem before on my old 4030 CNC that I modify. I suspect that even 1.5 kW for wood, given the limitations on X and Y speed, is more than enough, but it has ER20 collet which is much better than ER11. So, now I want to use this motor with my 6040 CNC with it’s standard VFD (1.5 kW).
As I understand, VFD is an inverter that rectify input power and charge large capacitors. This charge then used by high frequency convertor (10 – 50 kHz) to create 3 phase current of necessary frequency and, actually, voltage (output voltage can be set anywhere from 50 to 450 V according to the manual).
There is also settings for torque compensation at low RPM and general voltage/frequency curve set parameters. I actually found very useful documentation on this VFD: https://imaginieriecom.files.wordpre...umentation.pdf
It has this graph (attached)


So, it looks like I can associate max frequency (d005) 400 Hz to max voltage (d004) 110 V and limit minimum frequency (d007) to avoid stall and overheating.
Could you please give your opinions and recommendations?