2.2kw spindle+VFD: Can I power VFD via PDU?

I’m new to CNC and the forum. The shapeoko 3 XXL is still in the box at home waiting for me to setup when I get back from vacation in a few days, but I’ve been doing a lot of reading and plan to do some upgrades right off the bat. I’ve ordered the beaver HDZ and I’m going to order a 2.2kw water cooled spindle, and I’ll be using Universal G-code Sender.

Shoutout to @Luke for sharing so much valuable information on the forum. I’ve googled a thousand questions and always find myself back at one of your posts for the answers.

Anyway, intro over and now to my question:

I’m located in the USA but I have a 240 volt (max) outlet in my garage with this PDU plugged into it for my computers: [https://www.amazon.com/dp/B0007YG85A/ref=cm_sw_r_cp_api_i_pnNlCb3NHNBK8] .
Im wondering if I could power the 220 volt VFD for the water cooled spindle by simply using a C19 cord plugged into one of the C19 outlets on my PDU, with the other end of the cord cut off and wired to the VFD. I’ll use a 12 AWG cord. The C19 outlets on my PDU each have their own breakers rated for 12 amps each.
Does anyone see any issue with this setup? I’m kinda just seeking confirmation before I order the 220 volt VFD instead of a 110 volt VFD. I’m reluctant to use a 110 volt VFD because my 110 volt breakers are all rated for only 20 amps.

That’s my question, but any tips regarding the spindle and VFD setup, HDZ, and UGS are welcome.
Also, I would greatly appreciate any suggestions for making the SO3 more rigid. Having trouble finding anything on that subject. I plan to eventually mill some aluminum and maybe even some thin steel if possible.

Thanks in advance!

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Thanks for the order!

I’ve just had a look and whilst I’m in the UK and everything else runs fine 240v. From what I can see it should be fine but 12awg cord might be too thick for a spindle cable.

@HDRyder - Gary you have a pretty good setup there, are you running 220? I can’t recall?

I used 16 AWG from the VFD to spindle connection and it works fine.


Sorry I’m probably not explaining this very clearly lol. Or I might actually be way off base on how the VFD receives power…
What I meant is that I’ll use the 12 AWG cable to power the VFD. One end of the C19 cable plugs into the outlet on my PDU. The other end of the cable I will cut off and wire directly to the input of the VFD to supply power to it.

I may be under the wrong impression, but I believe the VFD is usually powered via cable directly from the breaker? Ive only got one 240 volt breaker though and I’ve got it running to an L6-30R receptacle with the PDU plugged into the receptacle. So instead of having to remove the PDU and receptacle, I’m thinking I should be able to power the VFD from one of the C19 outlets on the PDU.

Yes, 220/240 goes into the VFD (I used 12AWG) and 16AWG from the VFD to the spindle. I don’t have 220 on the side of my shop where the CNC is located, so I use a 5000W step up transformer plugged into a 20AMP 110 outlet and it works great.


My vfd is 220v the rest is 110v. What your planning should work fine. Pretty much how mine is set up. I’m plugged into one of my 50Amp welder outlets with a conversion cord fo make the plug fit. You should be good.

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It’s feasible to use your PDU to achieve 220VAC in the way you are asking if it is fed by single phase 220, however the breakers will not function properly for 220 if they are not tied together so both trip at the same time, which could cause damage to your equipment or worse.

Why not wire a load Center or get a spider box to break out the 220?

Got it all worked out and didn’t blow anything up lol.
The PDU powers the VFD fine even at full load and doesn’t trip the integrated 12-amp breaker on the PDU.
Thanks for the replies everyone!

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