Well I killed my spindle and vfd today. How can I test the pwm output on the carbide board?

Well, that might be good news,

How well insulated is the wiring inside that spindle? Any chance a wire was just shorting to the chassis? The closest to inside one of those I’ve seen is this video where the rotor is cooked and pressed out for a bearing replacement.

In terms of setup for the spindle, there’s a thread around here somewhere where a user (maybe Julien?) documented all the settings on their HY drive. There’s also this thread about 1.5kW HY drives.

I’m happy to compare settings from my (currently) working drive too when you get one that powers up if that helps.

I actually went through setting with two members of the Facebook group and had everything dialed in, to my knowledge.

I’m not sure about the inside of the spindle. I just removed the cap and didn’t want to go any further last Night. I’m case the seller wants it back. Don’t want to do anything else

The only thing sealing the coolant passages from the inside of the motor is 2 Little Orings.

I seem to have the same resistance between all my power pins. I’m still worried that something could be wrong with the spindle.

The worked using the VFD controls part of the experiment would back that up. There aren’t very many settings that relate to the external speed selection. Other than requesting a speed too close to zero and cooking the coils with something close to DC I’m not sure what else could go wrong. Mine doesn’t seem to care how slow it starts up using the knob on the front of the drive and the vendor who pre-configured it didn’t set any sensible minimum frequency, I keep meaning to reconfigure that…

Oh no, wasn’t suggesting pulling it any further apart.

Until the contact between ground and a phase pin is explained I’d also be wary of it. Just checking, is the connector properly polarised? Is there any chance it let you plug it in with the pins incorrectly matched?

It seems likely that a spindle fault could have zapped the electronics in the VFD and resulted in the overvolt or overcurrent that gave you sparks at the Shapeoko end, still amazed that board is still working, have you checked to see if there’s still any volts on the PWM pin at that end?

Spindle connector can only go in one way. And I’ve never taken the pins out at all. So I can’t see that being an issue. The wires have never been removed from the vfd once I got spindle rotation correct.

I’ll let you know what happens after running the chiller for a while.

Residential service in US is 2 phase 230Vac center tapped to “neutral” for 115Vac per phase. Neutral is connected to earth at the service entry panel/meter. In the old days 115Vac outlets didn’t even have a third connection for earth ground! Nowadays they should, and those in wet locations are supposed to be protected with ground fault detectors/interrupters. Except for the three phase service, Is that basically how it things work in the EU?

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Did a bit of reading and it seems that the UK is a bit behind Europe. It appears that in much of Europe 3 phase 400V to the home is quite common, this is very helpful for things like solar power refeeding the grid and electric car chargers as well as people with Bridgeports in their garages.

Normally I believe we reduce 11kV or 33kV to 400 / 230 at the substation, the 400V is the inter-phase voltage and the 230V is the phase to neutral voltage, this is achieved by a Wye (star) connection of the phases at the transformer secondary. 3 Phase is delivered as 4 wire, 3 phases, and neutral so you can do single phase, delta and wye connections. Single phase comes as 2 wire, one phase, shared neutral and local earth. The neutral is earth bonded at the substation ( I think ) and it’s fairly common to be able to measure a few volts between this and your local earth due to phase load imbalance and resistive losses in the neutral return to the substation. Wikipedia has an interesting map of who gets what Voltage and Frequency where around the world.

Japan has a particularly messy grid system with half of the Island using US spec power and the rest using European spec power. This means both 50Hz and 60Hz as well as different voltages between the two parts of the country which was part of the reason for the severe power shortages when the nuclear plants were shut down after the Tsunami, there was very little HVDC interconnect to allow power to be redistributed across the country.

Japan looks more like the US however in terms of wires on poles as they apparently prefer not to bury cables due to earthquake risk.

For a country where everything else is so professional, neat and tidy I was very surprised by the wiring that looks like they forgot and had to pull extension leads overnight.


Well dealing with the Chinese is not my favorite thing. After 3 days of sending them messages with no reply I filed a dispute. 10 minutes later I started getting responses.

The language gap and the attitude make things difficult. They are purely defense with no true want to resolve the issue.

They say the spindle is ok and that the vfd is bad. They say I have voltage on the spindle case because it is back feeding through the ground. It kind of makes a little since. They say the vfd has had a capacitor failure and that I need to replace the capacitor, they can’t tell me where it is, what the specs are and have not replied to my requested to have the vfd replaced.

The dispute was responded to by alinexpress. They are have a couple options. In order to receive a fill refund including my shipping costs ($160 in shipping) I would have to ship it back to them on my dime. To get a total of $380 back. So I after shipping I would get $220 back. Or option b is I keep everything and get $180 back.

Think I’m going to go with option b. I can get an identical vfd on amazon for $130 plus a 4 year warranty for $30. And I still have the spindle which according to them is still good.

I’ll see if they rely tomorrow.

I wanted to be sure the power to PE measurement you stated above was on the VFD. Have you checked the motor? 3 phase brushless motors should have equal low resistance measurements between the motor phases (U, V, W). When measuring from phase to case/PE the phases should all read open. Motor measurements should be made with the motor disconnected from the VFD. If you have not done so yet measure the pin combinations for the motor (U-V, U-W, V-W, PE- case, U-PE, V-PE, W-PE) to ensure it is healthy. If the spindle is damaged and you connect it to a replacement VFD it could be damaged. I’d hate to see you go thru all this just to start right back at the beginning.


It has 1.5-1.7 ohms between all the phases and open to ground on all three.

They are saying that it has voltage on the motor case because it’s back feeding through the ground.

When it I get home today I’m going to remove the ground wire at the vfd to double check this.

I would not recommend ‘replacing the capacitor’ on this drive without a full circuit diagram, appropriate test rig and handy fire extinguisher.

If they have diagnosed this event to “failed capacitor” with only the remote info so far that suggests this is a common failure mode for the drive, alternatively it might just be ‘name a technical problem’.

I really wouldn’t go opening that up and replacing parts in it, there’s no realistic way to tell what else might have been damaged during this failure without access to the drawings, specs and test rig.

It’s also a shock hazard, there’s > 300V DC on the big reservoir caps in there and more than enough current to kill you quite quickly.

Did you actually get a quote for the shipping costs back to China? From what I’ve heard shipping back into China is rather more expensive than shipping out.

If the spindle is indeed good, I’d take the money and get a replacement drive.

That’s pretty close to what my 2.2kW spindle reads, I have 1.5 Ohms pin to pin and nothing to ground from any winding.

It’s entirely possible it’s the VFD yanking it to ground, if so the “failed capacitor” could well be a short circuit failure of one of the filter capacitors between VFD line and ground. Sorry, I hadn’t realised in your earlier posts that the spindle was still attached to the drive when you said there was winding to ground connectivity.

That’s good news on the motor readings. A new VFD should get you back in business. Personally I’d take the money and invest in the other VFD you mentioned. A cap failure of this nature after so little use is indicative of poor design, shotty components, or both. If you crack it open I would be interested in the autopsy photos to see what we can learn but would not recommend trying to revive the patient.

This is a hy inverter. So I am surprised it failed but shit happens. I’m going to get the same model number inverter again from amazon with their 4
Year warranty and see what happens. I accepted the $180 refund. Waiting on seller to approve but I don’t think they have to. The seller has stopped replying to my messages so I’m done trying to deal
With them.

I’m quite surprised at the AliExpress customer service, didn’t think that would be very good, but they’re better than I thought.

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Seems quite reasonable to me!

You decided that it was from pulling it apart then?

Yes. I let the chiller run for two days non stop. Used a vac. Fluid evaluator and sucked the coolant out through the lines. Opened it back up and it was dry in the electrical portion.

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Great! It would be good to know when/if you get you refund!

I’m surprised the Shapeoko controller board isn’t toast. Did you let the magic smoke out? Electronics don’t work without the magic smoke.


I’m moving everything over into my enclosure tonight. Once I get power to it I’ll check.