There are NEMA 5-30 receptacles and plugs that are 120v 30A rated if you go this route.
Hey Derek,
30 A can not be enough, thatās why I still insist sometimes. Can calculate it for you but not today, Just think of that you have a single phase AC at input, that gets rectified and stored in capacitors, and then a microcontroller switches six IGBTs on and off to form three phases on three different wires at the same time of the max. current that the VFD is rated at output. If you look at the overlying waveforms of the three phases on three-phase electricity, it is clear that at the input, you will at least draw the double current at the input as what the VFD 3-phase rated output current is. And then you add the efficiency of the VFD itself and it gets even more. If you take the strongest motor that is rated for a 2.2 kW VFD which is usually 10 A on 200 V class and 20 A on 100 V class, and consider this with the induction motor formula you find here, it is clear that for a 2.2 kW motor you have more than 4.2 kVA input which at 120 V is already 34 A, and you also see the usual capacity ratings on 2.2 kW VFDs of 4.5 kVA in the manual, and then add the efficiency loss of the VFD itself, it is clear that you would recommend to connect a device of about 40 A max. input rating to a 120 V circuit, knowing that the maximum domestic 120 V circuits are only 30 A strong. An electrician can not do this! Or I need to revise my view about electricians.
I could also try to make it comprehensible in another way, for all who fear the formulae etc.: Here is a single-phase input VFD of the 200 V class for a 2.2 kW motor, it is able to deliver 12/11 A (depending on duty cycle) and at its input, it is rated 24/22 A. In the manual, the fuse recommendation is 30 A for this model.
The same model, if it existed, for 100 V class (they donāt make those), would be for max. 24/22 A spindles, and could be assumed to be rated the double then as 200 V class model, thus 48/44 A input current. And the recommended fuse even bigger.
Ok that does make since. And sorry if this is making you repeat your reply but want to MAKE SURE I completely understand your info.
And for the 110V im sticking with just because its quit costly having to switch to 30amp circuit and having use 220 plugs and so on (based off what little info I know about electrical that is).
Also based off what you said. The Makita router which Onefinity does suggest using with their machine runs off 120V 6.5 amps which is to āassumedā is going to push past the 0.75kW you were saying to avoid. Now assuming this is correct of course.
I did go back and read about 2.2kW and that I guess makes since. So I suppose I will not purchase one of these spindles then as it seems to be or not to be the correct choice.
Iāll just keep looking and in the mean time if anyone has suggestions of spindles to look at Iāll take it. thanks
Be careful of dusty nuts. I can understand the benefit of a quick swap out but balance that with checking for dust build up in the collette as that requires taking it out and giving it a blow.
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Hey Sean,
you canāt compare the power rating of the Makita router to the rated spindle power. If the Makita draws 6.5 A @ 120 V = 0.78 kVA, that is the electrical input power. According to IEC 60034-1, the rated output of a motor has to be the mechanical power available at the shaft, NOT the electrical power it draws. That current is higher. If you take the electrical power of the Makita router and take into account that a universal motor has an even worse efficiency compared to a spindle, you can expect that the mechanical power of the Makita is well below 0.5 kW. Unfortunately they donāt provide the data, they just mention the electrical input power 
Also the motor characteristic strongly differ between the two (as compared here), so the watts alone donāt really help.
Gotcha.
So I guess this would be the only other question for you then.
Can you suggest a spindle based off info provided ?? Id really appreciate any recommendations! Of course ill do my best to research before purchasing.
Running a 20amp breaker, standard receptacle to match. Ive looked into some spindles and āmayā go that way even tho in my option its over priced, BUT they say they are āplug and playā ready to go, and do seem to be able to work on a standard 20amp circuit.
Trying to get this figured out so I can move forward. I appreciate all the input!! Thanks
I also have an HY 2.2kw spindle and bought these nuts off of ebay.
https://www.ebay.com/itm/164090640143
They work just fine. That being said I need to get more as I thought having one collet of each size would be enough but Iām finding that I actually want 3 or 4 1/4" collets/ nuts to speed up switching bits. My spoilboard flattener is 12mm so the collect and a nut always stay on it in itās case. As for the nuts, they feel like they ar good quality.
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Hey Sean,
I am always a bit reluctant to say what I bought because many people here donāt want to spend that much money, but of course I can tell you what I got:
But I would rather have bought the ATC model, but at that time my money was not enough:
Ok thanks ill look into it
I donāt disagree with you but the label/manufacturer instructions are the law in North America regardless of the calculations unfortunately (in theory a licensed electrical engineer could tell you differently but theyāre usually not going to unless they represent the manufacturer of the VFD). The other angle is that the input values are correct but the output values are not accurate.
Honestly Iāve tried finding something else in this forum but all anyone can suggest is a spindle thatās$1000 and thatās not including all accessories to go with it. Iām not spending that much when I havenāt even gotten the machine yet, itās just not happening! Chinese or not Iāve heard from others who have made the exact spindle that Iām getting work and are running it on the same side circuit I will be so it should be okā¦.
I appreciate all the help guys it definitely helps! I havenāt bought the spindle yet so Iāll still be searching until I either just buy that one or another. Thanks!
Hey Derek,
we are still talking of the calculation of the (missing in manual and nameplate) maximum input current rating of this VFD and what to tell someone who wants to connect it, what circuit one would need. You have the specs of the three-phase output current it can deliver: 20 A 110 Ā±20% V 3~.
Anyone can verify by calculation, and especially if you are an electrician, you should be able to simply calculate what total currents are flowing in a three phase current of known current and voltage at any time. And if you have a device that draws this power from one single phase input, nobody can have a doubt on what I explained above. You donāt want to tell that if you know for sure a device is able to draw at least 40 A as maximum input current (and that itās what should be in the manual and the nameplate), that it is correct to recommend to the people to connect it to a circuit that is too weak for this, just because the input rating is (willingly) not there? Sorry for the question, I only ask to be sure.
I always say, to connect a VFD, you need an electrician ā I want to be sure that it is still a correct recommendation 
What do you mean by this? Please could you explain what you mean.
Hey Sean, There are quite a few different options. Consensus seems to be that if you can make it work, 2.2kW spindle on 240v circuit is often your best bet. If not, maybe up to 1.5kW on 120v. All depends on what you want to do with your machine as well, of course.
As far as spindle and VFD brands go, there are many possibilities. Cheapish Chinese VFD/spindle such as Huanyang and many others. Good VFD (Hitachi/Omron/Delta, etc) with presumably better quality Chinese spindle like Jianken, or possibly G Penny and others, that comes straight from the factory. Thatās what I did. Or, if you have the money and/or looking for more professional equipment, a good VFD with something like a Mechatron (Germany) or CNC Depot ATC (U.S.) spindle. Quite a bit of difference in risk/reward, quality, and cost.
PWNCNC is probably somewhere between cheapish and middle of the road, and also includes service and warranty I believe.
I donāt think I saw it mentioned in the post, so just in case you havenāt looked in to this, keep in mind that if you donāt buy something like the PWNCNC kit (or similar) with the premade cable from VFD to spindle, youāll have to source the right shielded cable and do the somewhat tricky job of soldering the wires to the four cup connectors in the aviation connector that comes with the spindle. Often a proper shielded cable also does not easily fit in to the aviation connector to begin with.
Youāll get lots of opinions on this, so if you have the time, Iād recommend digging around the forum and maybe other CNC forums so you can form your own. Good luck!
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Hey Sean,
I agree to Martin @MVall and would add that it is always the best to buy the spindle cable ready-to-use with the spindle from spindle manufacturer. Reputable spindle manufacturers always offer this.
Another manufacturer that offers spindle/VFD kits ready to use is Mechatron (see here) (Unboxing video). There are many more spindle manufacturers but Mechatron is often mentioned because they also address consumers. They even have an ebay shop.
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Hey Sean,
PS: The 0.75 kW limit for spindles that you would run on a 120 V circuit is not really the limit, it is just the strongest VFD what Hitachi offers for 120 V. The 100 V class WJ200-007M VFD for a spindle motor that delivers 0.75 kW mechanical power on its shaft is rated with 2.4 kVA capacity, which would mean 20 A input at single-phase 120 V, so to be within the 30 A circuit capability of the U.S. domestic 120 V circuits, an approx. 1.1 kW spindle with a VFD made for this spindle power would be the limit.
When you say you could calculate the input current youāre assuming the rated output wattage is accurate. Perhaps the reason the max input current nameplate value on a 120v 2.2kw VFD is 22A is that the output really isnāt 2.2kw and might only be 1.5kw making the input value correct in the calculation. 1.5kw output would still drive the 2.2kw spindle, just not to itās full potential. We donāt know which value, input or output or neither is accurate 
Hey Derek,
the VFD in question writes clearly in manual and nameplate that it is capable to deliver 20 A @ 110 Ā±20% V 3-phase electrical output. So an electrician can not argue āThis is what the manual and the nameplate say, but letās assume it is wrongā. Youāre not serious. As an electrician, you are asked to dimensionate the circuit with these data.
20 A @ 110 Ā±20% V 3-phase output, this is 4.156 kVA capacity (120*20*sqrt(3)) of the VFD. So if you expect this power to be drawn over a single-phase 120 V input, you can assume this can in no case be a max. current of less than already 34 A. (4156/120). And this does yet not account for the efficiency loss of the VFD, which of course is there since it has to first create these currents with its circuit over the DC stage and the IGBT array, and all these have power loss.
You speak in absolutes about this topic when the reality is we just donāt know if input rating, output rating, or neither is correct. Your calculations are based on the assumption the output value is the correct one therefore the input would be incorrect, we donāt know that.
As an electrician the input nameplate or documentation (or engineered plans with a seal of a PE) is all that mattered, ever, period. If it said 22A it was not in my authority to question it or produce my own calculations.
This thread is going sideways as all seem to do when VFDs are involved, I get your point of view and Iām not saying itās wrong, there is no way to know if the sketchy documentation has an accurate input or accurate output or neither to definitively validate the actual input current.
Hey Derek,
based on your reply I think you did not read carefully what I wrote.
If we both are still talking of the specific VFD mentioned above, it is crystal clear what the manual and the nameplate of this VFD say: 20 A @ 110 Ā±20% V 3-phase electrical output capacity. When you are an electrician, and you have a clear statement of the VFD manufacturer which gives you the specification of the ouput rating (and we have this here), I believe your duty would be to calculate the input circuit required, based on these data that are there. I believe you cannot say āLetās ignore what the manufacturer wrote into the manual and on the nameplate, because it could be wrongā.
If you really mean what you say here, the conclusion must be that you would in any case refuse to connect the specific VFD mentioned above to any supply circuit. Okay, I would support that. Perhaps itās better than what I say (which is to at least dimensionate a 45 A circuit, I still believe you would be on the safe side with that).
In my opinion, even if I never would recommend these cheap chinese VFDs, I would still think you can make a safe statement on the dimensionating of the input circuit, by taking the manual and nameplate statement on output power. If you have such a clear statement of the rated output of a VFD, and the input rating is missing, of course you can (and an electrician in my opinion should, at least it is desirable) calculate the approx. input rating (of course one would need some knowledge on how a VFD works).
I donāt know which 120 V 2.2 kW VFD could have a 22 A input power rating, you did not show this somewhere. I have seen this nowhere.
By the way, the ā2.2 kWā rating of a spindle, according to IEC 60034-1, does not mean its electrical input power. And the VFDs manufacturer, when they call a VFD model a ā2.2 kWā model, this always means āfor a 2.2 kW motorā, and does not mean any electrical rating of the VFD, but the mechanical power at the spindle shaft of the motor for which it is suited. A ā2.2 kWā VFD usually has a capacity of approx. 3.8 to 4.5 kVA. And that is not yet the VFD input power, just the capacity it can deliver to the motor.
I know what you mean, but here, this should not apply. You are not talking to someone here that simply believes to be right, as is widely found on the web. I can grab into my bookshelf next to me at any time and look up if Iām right. So of course we finally wonāt disagree (at least not if Iām right with how I see you).
PS: I see you will reply again, but I only woke up in the middle of the night to go the can, itās 5:56 AM here ā¦
What is the nameplate input rating? In the absence of specific manufacturer instructions (or engineered plan) that is all that matters to an electrician.