[XYZGnomon]

Actually 110V, 3 phase, 400 Hz does exist, it's an aircraft power systems standard, but I'm not sure if it is still in use in newer aircraft. Also interestingly enough, according to the data tag, the Delta 7.5kW servo spindle motor on my lathe is a 110V, 3 phase, but the drive is 230V, 3 phase input.

But using 120V, 3 phase, with a 120V single phase input to try to run a router spindle seems a bit useless.

Hey Jim, long time no see! I'm not using my real name here, but let's just say I used to make bicycles in Portland and you were very helpful to me when I was getting my machine shop up after I got out of the Army. I moved on to Solidworks design and CAM programming in another state and eventually got a job making high pressure valve components on multi-axis machines at SpaceX here in Los Angeles, where I am now.

I bought an Avid router for my home shop, and - because everything is gas in Los Angeles - unfortunately I only have access to regular domestic power. As an apartment dweller in Hollywood, I'm lucky to have a shop at all, so any discussion about 220V single phase is just not worth having. I am trying to figure out how to make this work with only a single 20A circuit. Okay, with that out of the way...

Can we agree that 230V/3PH is just three legs of 110V, 120 degrees out of phase of each other? IN THAT CONTEXT, how is 110V/3PH different? We can talk amps all day, and square roots of three and whatever you want. So far, pretty much everybody here has given half of an explanation for some reason and/or in run on sentences that go nowhere. Also, the explanations seem to be wrapped up in a message about not using a particular product that has nothing to do with my question.

[Jim Dawson]

Hey Jim, long time no see! I'm not using my real name here, but let's just say I used to make bicycles in Portland and you were very helpful to me when I was getting my machine shop up after I got out of the Army. I moved on to Solidworks design and CAM programming in another state and eventually got a job making high pressure valve components on multi-axis machines at SpaceX here in Los Angeles, where I am now.

I bought an Avid router for my home shop, and - because everything is gas in Los Angeles - unfortunately I only have access to regular domestic power. As an apartment dweller in Hollywood, I'm lucky to have a shop at all, so any discussion about 220V single phase is just not worth having. I am trying to figure out how to make this work with only a single 20A circuit. Okay, with that out of the way...

Can we agree that 230V/3PH is just three legs of 110V, 120 degrees out of phase of each other? IN THAT CONTEXT, how is 110V/3PH different? We can talk amps all day, and square roots of three and whatever you want. So far, pretty much everybody here has given half of an explanation for some reason and/or in run on sentences that go nowhere. Also, the explanations seem to be wrapped up in a message about not using a particular product that has nothing to do with my question.

Hey! Small world, it has been a while. Sounds like you are doing well. I have added a bit to my shop since you last saw it, have a Hardinge CNC lathe and a Haas TM-2P now. Both are making parts as I type this. Been a bit busy.

Not exactly, 230V 3 phase is 3 legs of 230V, 120 deg out of phase with each other. 230V 3 phase is kind of an oddball in North America today, at least as supplied by the power company, more common is 208/120V and 460/277V. I'm not going to go into a long explanation about why this is. ADX was wired for 230V 3 phase, but that was a very old power system.

Functionally, 110V, 3 phase is just like any other 3 phase voltage, no difference at all. Just not a good fit for 120V domestic power.

I would hang a Dewalt router motor (because Porter Cable stopped making the 7518 motors) on your machine and be done with the problem.

[mactec54]

I bought an Avid router for my home shop, and - because everything is gas in Los Angeles - unfortunately I only have access to regular domestic power. As an apartment dweller in Hollywood, I'm lucky to have a shop at all, so any discussion about 220V single phase is just not worth having. I am trying to figure out how to make this work with only a single 20A circuit. Okay, with that out of the way...

For the first time you posted what you are trying to do

If you only have a 120v 20A supply then you could run an 800W 24,000 RPM water or air cooled spindle using the HY VFD Drive that has the 110v /120v input and 110v 3Ph output for your spindle

Or like Jim has said use a regular Router a lot of noise with this option and with any air cooled spindles

There are other things that can be done but you don't have enough Supply amps or the wiring to support it

[XYZGnomon]

I learned something today. For the longest time I was confused (still am!) about this stuff. I actually ran a 3HP single phase motor on a Bridgeport clone I bought brand new, with two 110/115/120V outlets on different circuits and it worked fine most of the time. I honestly thought that 230V (or however many volts!) just added another leg. Now I know that it doesn't, and that gives context to how 110V/3PH can even exist. Thank you Jim! mactec54 I know your heart is in the right place, but you don't make it easy to understand what you're trying to say.

I have already purchased https://www.aliexpress.com/item/1005002504467195.html and it works flawlessly on https://www.electricmotorwholesale.com/9675-KBDF-27D/ but I have been forced to seek a different setup because for some reason the KB drive only goes to 240Hz.

Since writing the earlier posts, I got a step-up transformer to use with whatever future VFD I get, and a few minutes ago I accidentally fried the KB. It was expecting an L1 & L2, each with 115V, but the transformer shoved 230V into L1.

How do Europeans wire their VFDs? Don't they also have one hot leg and a neutral?

[Jim Dawson]

I have already purchased https://www.aliexpress.com/item/1005002504467195.html and it works flawlessly on https://www.electricmotorwholesale.com/9675-KBDF-27D/ but I have been forced to seek a different setup because for some reason the KB drive only goes to 240Hz.

Since writing the earlier posts, I got a step-up transformer to use with whatever future VFD I get, and a few minutes ago I accidentally fried the KB. It was expecting an L1 & L2, each with 115V, but the transformer shoved 230V into L1.

How do Europeans wire their VFDs? Don't they also have one hot leg and a neutral?

You need to stop thinking in terms of 120V legs, that is only valid between a hot and the neutral. North American single phase power is 240V. The transformer is center tapped at the pole and the neutral is connected there. That is how the 120V is derived, between a hot leg and neutral. So it is possible to pull 240V off of 2 separate 120V plugs if each is wired to the opposing legs. But this is not recommended.





European power is 400V, 3 phase, Y connected, with the neutral connected at the center of the Y to derive 230V single phase for domestic use.

[XYZGnomon]

And I used a step up transformer to get the exact same thing as European domestic voltage, which is why I asked! I was going to return it, but now I just have to chalk it up to ignorance on my part.

In terms of what spindle drive to use, I recognize that I can't go higher than 1-1/2HP, and it probably makes sense to stick with 1HP. ER20 is non-negotiable, and until an off-the-shelf router comes with that taper I'm going to have to use a real spindle with an under-rated VFD.

[mactec54]

I learned something today. For the longest time I was confused (still am!) about this stuff. I actually ran a 3HP single phase motor on a Bridgeport clone I bought brand new, with two 110/115/120V outlets on different circuits and it worked fine most of the time. I honestly thought that 230V (or however many volts!) just added another leg. Now I know that it doesn't, and that gives context to how 110V/3PH can even exist. Thank you Jim! mactec54 I know your heart is in the right place, but you don't make it easy to understand what you're trying to say.

I have already purchased https://www.aliexpress.com/item/1005002504467195.html and it works flawlessly on https://www.electricmotorwholesale.com/9675-KBDF-27D/ but I have been forced to seek a different setup because for some reason the KB drive only goes to 240Hz.

Since writing the earlier posts, I got a step-up transformer to use with whatever future VFD I get, and a few minutes ago I accidentally fried the KB. It was expecting an L1 & L2, each with 115V, but the transformer shoved 230V into L1.

How do Europeans wire their VFDs? Don't they also have one hot leg and a neutral?

230 /240v is the same no matter where you live L1 and neutral Plus Ground is the same as L1 L2 and Ground in NA

You wired it incorrect or it would of been fine, if the drive rated for 240v or was it rated for 120v

There are a lot of users here on the zone that have used that transformer and run a 220v Drive and motor with

[mactec54]

And I used a step up transformer to get the exact same thing as European domestic voltage, which is why I asked! I was going to return it, but now I just have to chalk it up to ignorance on my part.

In terms of what spindle drive to use, I recognize that I can't go higher than 1-1/2HP, and it probably makes sense to stick with 1HP. ER20 is non-negotiable, and until an off-the-shelf router comes with that taper I'm going to have to use a real spindle with an under-rated VFD.

You can't use an under rated VFD Drive if anything it has to be over rated or you will damage it

There are many here on the zone that are using the same transformer without any problems

Did you have a spindle attached to the VFD Drive ???

[StrawberryBoi]

Why can't he use an underrated VFD? The current is always limited by the VFD and not the motor, excepting short circuit and step response currents.

As long as he doesn't actually program the VFD somehow to go over it's capacity, it is the limiter, assuming the load motor is rated at or above the VFD output voltage.

It's the reverse, running an overrated VFD on an underrated motor and then trying to push the motor well outside it's rating that will cause failures.

The one caveat is if the lower rated motor induction is far too low or too high, which is very unlikely unless it's a PMAC servo device.

[XYZGnomon]

Why can't he use an underrated VFD? The current is always limited by the VFD and not the motor, excepting short circuit and step response currents.

As long as he doesn't actually program the VFD somehow to go over it's capacity, it is the limiter, assuming the load motor is rated at or above the VFD output voltage.

It's the reverse, running an overrated VFD on an underrated motor and then trying to push the motor well outside it's rating that will cause failures.

The one caveat is if the lower rated motor induction is far too low or too high, which is very unlikely unless it's a PMAC servo device.

Thanks for taking my side! ER20 is simply not negotiable, and I have no plans to mill depleted uranium or any other materials that don't belong on a router made of extruded aluminum anyway. I doubt I will ever draw much more current than if I used a Makita or some other trim router, but one thing I will have is my hearing intact! As a two-for, there's also much lower runout and vibration. Everybody wins!

This is it, BTW, right after unpacking it:

[mactec54]

Why can't he use an underrated VFD? The current is always limited by the VFD and not the motor, excepting short circuit and step response currents.

As long as he doesn't actually program the VFD somehow to go over it's capacity, it is the limiter, assuming the load motor is rated at or above the VFD output voltage.

It's the reverse, running an overrated VFD on an underrated motor and then trying to push the motor well outside it's rating that will cause failures.

The one caveat is if the lower rated motor induction is far too low or too high, which is very unlikely unless it's a PMAC servo device.

I guess you should know what you are talking about but this is not the case with an install like this, you will fry one or the other or both if you don't get the right VFD Drive that can handle the single phase input and the spindle needs to have a lower rating than the VFD Drive

An under size VFD Drive will fail, no matter what your Tec tells you or you think should work, this is all about single Phase supply to a 3 Ph VFD, the simplest of Math tells you it has to have a higher rating than the spindle 1.73 times plus a safety factor

The discussion is about a regular 2 Pole 18000 300Hz 6.5A 220v Ac motor

A snippet of what is required to run a motor like this on single phase, if the VFD Drive does not have the required Input Amps required then it will fry, it usually take around 5s to 30s and it is done

[StrawberryBoi]

This is assuming he runs it at full current though. The VFD only knows about the motor what you tell it. A motor with identical reactance can be 500W or 500kW. There is no way for it to tell itself to go harder than it's own rating.

Honestly, I'd really just like to understand how the VFD will damage itself. The VFD is doing the work of managing the phase outputs.

The usual drive failure cases are from overvoltage due to back driving the motor beyond the drive ability to handle, modifying drive parameters to operate out of it's hardware limits (which is bad design on the drive software, but I'd totally buy that being a real issue), and/or faulty control by the VFD. Other than the backdriving case, there are almost no cases where motors will damage a drive that is operating under control.

Power ratings and current ratings on these devices are semi-arbitrary and not intrinsic. The case for an overrated motor damaging a drive just makes no sense to me, please help me understand.

[mactec54]

Thanks for taking my side! ER20 is simply not negotiable, and I have no plans to mill depleted uranium or any other materials that don't belong on a router made of extruded aluminum anyway. I doubt I will ever draw much more current than if I used a Makita or some other trim router, but one thing I will have is my hearing intact! As a two-for, there's also much lower runout and vibration. Everybody wins!

This is it, BTW, right after unpacking it:

So little by little you post what this is all about you have a 1.5Kw 300Hz 6.5A 220v spindle

So your 120v single phase supply needs to be greater than 22.49A , 25A would be the minimum to run this spindle at it's rated amps so with the right VFD Drive and the correct Parameters set you could be running with your 20A supply but expect it to trip some times, many have been down this same route before you, so there is nothing out of the ordinary about what you are wanting to do

[StrawberryBoi]

Yes, otherwise you will be running your spindle at much lower than it's rated capacity and just wasting that spindle, but not tripping the circuit.

[mactec54]

This is assuming he runs it at full current though. The VFD only knows about the motor what you tell it. A motor with identical reactance can be 500W or 500kW. There is no way for it to tell itself to go harder than it's own rating.

Honestly, I'd really just like to understand how the VFD will damage itself. The VFD is doing the work of managing the phase outputs.

The usual drive failure cases are from overvoltage due to back driving the motor beyond the drive ability to handle, modifying drive parameters to operate out of it's hardware limits (which is bad design on the drive software, but I'd totally buy that being a real issue), and/or faulty control by the VFD. Other than the backdriving case, there are almost no cases where motors will damage a drive that is operating under control.

Power ratings and current ratings on these devices are semi-arbitrary and not intrinsic. The case for an overrated motor damaging a drive just makes no sense to me, please help me understand.

Keep dreaming it does not work like that and of all people you should know better, what happens when the motor is stalled which will happen, the result will be smoke I guarantee

There have been many failures on here just reading post like this, put your name to it, they will fail if they listen / read take your advice

[mactec54]

Yes, otherwise you will be running your spindle at much lower than it's rated capacity and just wasting that spindle, but not tripping the circuit.

It will still trip it, with the 20A supply

[StrawberryBoi]

That's fine, I still want to know WHY. There is no electrical reason for the VFD to overcurrent on a stall unless it's just a ****e product and it shouldn't ever be driving anything imho. A stalled motor condition is a real condition that can occur regardless of whatever is printed on the motor nameplate, the VFD should always be able to handle it. Startup is a temporary stalled condition just the same. Why would a say, water cooled 5kW motor and the exact same motor not water cooled at 1.5kW be different in stall? The only difference is how quickly the motor will blow, not the VFD. The resistance on the lower rated motor will increase marginally up until it either welds a short or blows a phase to open, either case is an internal motor failure and not an internal drive failure.

If you can point to a specific brand/model that has this design fail, then absolutely please do so. This is just not a universal issue, not even to specific country of origin product.

Again, honestly trying to understand. Hand waving is not explaining.

[XYZGnomon]

This has been fascinating. Since I destroyed the VFD by plugging it in after a step-up transformer (without changing any jumpers), I decided to tear it apart and I think I can fix it. I'm pretty sure that I fried one specific electrolytic capacitor, but I'll keep testing them as I desolder them.

KB says this only delivers 1.5HP when powered from 115V, and I believe it. I'm also okay with it. I've also had second thoughts about even needing this to spin above 14,400RPM, which is the speed at 240Hz, the max frequency of the drive.

If I can't get it to work satisfactorily, I am considering getting the 1HP GS20 drive from Automation Direct. That solves the power issue, but I don't think I can satisfy mactec54

[mactec54]

This has been fascinating. Since I destroyed the VFD by plugging it in after a step-up transformer (without changing any jumpers), I decided to tear it apart and I think I can fix it. I'm pretty sure that I fried one specific electrolytic capacitor, but I'll keep testing them as I desolder them.

KB says this only delivers 1.5HP when powered from 115V, and I believe it. I'm also okay with it. I've also had second thoughts about even needing this to spin above 14,400RPM, which is the speed at 240Hz, the max frequency of the drive.

If I can't get it to work satisfactorily, I am considering getting the 1HP GS20 drive from Automation Direct. That solves the power issue, but I don't think I can satisfy mactec54

The GS20 or the best would be the WEG CFW300 is a very good VFD Drive and will do everything you need 120v input 220/240v output and is sized for your spindle because it is rated for single phase input

Your spindle needs a minimum of 300Hz programed in the drive

[mactec54]

This has been fascinating. Since I destroyed the VFD by plugging it in after a step-up transformer (without changing any jumpers), I decided to tear it apart and I think I can fix it. I'm pretty sure that I fried one specific electrolytic capacitor, but I'll keep testing them as I desolder them.

KB says this only delivers 1.5HP when powered from 115V, and I believe it. I'm also okay with it. I've also had second thoughts about even needing this to spin above 14,400RPM, which is the speed at 240Hz, the max frequency of the drive.

If I can't get it to work satisfactorily, I am considering getting the 1HP GS20 drive from Automation Direct. That solves the power issue, but I don't think I can satisfy mactec54

What jumpers where there to be changed ???