[suganesh95]

Hello everyone.

I purchased a Chinese spindle via AliExpress. It is a 1.5 kW, 24000 rpm, ER16 liquid-cooled spindle.
When I run the spindle above 11,000 rpm it makes some kind of rattling noise like something is interfering inside, but the shaft spins smoothly and below 11,000 rpm the noise disappears. There is no resistance felt when I spin the shaft with my hand. It is perfectly smooth. I contacted the seller and he said it is normal and that I continue to use it. But the noise is quite worrying me.

https://www.youtube.com/watch?v=LrzEDfsBpPY

Since I was just testing the spindle for a few seconds I did not connect the water cooling tubes yet (in the video). Later I did a long run (running continuously for about an hour) with the tubes connected and water flowing through it, the spindle seemed to be working fine, no overheating or reduction in speed except for the noise it keeps making.

Can anyone tell me what is the problem? Is it all right to continue using it? Or what can be done to stop the noise?

Thank you !

[CitizenOfDreams]

Notice how the frequency of the noise stays the same as the spindle spins up and down? Just a wild guess, but I suspect it's VFD output that has little "glitches" in it.

Try this: change the VFD stopping mode from "Decelerate to stop" to "Coast to stop". See if the noise goes away as soon as you hit the Stop button.

[suganesh95]

Thank you for your reply!

Will check and let you know.

[suganesh95]

CitizenOfDreams you are right! There is some kind of glitch from the VFD output. I changed the settings as said by you and the noise disappeared as soon as I pressed the stop button. Can you further help me in correcting the issue? Any changes in VFD settings ? I am using a cheap chinese VFD. Model : YL620-A 2.2kW output and the spindle is a 1.5kW 400Hz model.

Thank you!

[CitizenOfDreams]

CitizenOfDreams you are right! There is some kind of glitch from the VFD output.

I would try changing the carrier frequency and see what happens.

[suganesh95]

Honestly, I'm a newbie and there are many settings in VFD that I am not able to figure out what they mean. I am uploading pics of my present settings and maybe you can help me out with it.

(P.S - Ignore the stopping mode as I have set it to "coast to stop")

Thank you.

[CitizenOfDreams]

Is this a complete list of functions? Looks like there should be much more. The "Carrier frequency" parameter is usually way down the list.

[CitizenOfDreams]

Carrier frequency, or PWM frequency, is parameter P12.19. Try cutting it in half or doubling it and see what happens.

[mactec54]

Carrier frequency, or PWM frequency, is parameter P12.19. Try cutting it in half or doubling it and see what happens.

You are miss leading this new user if he has not changed the carrier frequency then the default setting is fine for these spindles, his main Parameters are not set correct this is something you can't make guesses with

[suganesh95]

Really sorry for the delay in reply as I was having my exams so was busy preparing for it.

CitizenOfDreams

Actually, I did a factory reset and the default parameter for P12.19 was set to 6kHz in the VFD and not 8kHZ as mentioned in the manual. So what I did was I set it to 8 to check what happens. and the noise reduced drastically. Only a feeble amout was audible when went closer to the spindle to hear it. Later i set it to 10kHZ and the noise disappeared !

So do you recommend 10kHZ for my spindle?

[mactec54]

Hello everyone.

I purchased a Chinese spindle via AliExpress. It is a 1.5 kW, 24000 rpm, ER16 liquid-cooled spindle.
When I run the spindle above 11,000 rpm it makes some kind of rattling noise like something is interfering inside, but the shaft spins smoothly and below 11,000 rpm the noise disappears. There is no resistance felt when I spin the shaft with my hand. It is perfectly smooth. I contacted the seller and he said it is normal and that I continue to use it. But the noise is quite worrying me.

https://www.youtube.com/watch?v=LrzEDfsBpPY

Since I was just testing the spindle for a few seconds I did not connect the water cooling tubes yet (in the video). Later I did a long run (running continuously for about an hour) with the tubes connected and water flowing through it, the spindle seemed to be working fine, no overheating or reduction in speed except for the noise it keeps making.

Can anyone tell me what is the problem? Is it all right to continue using it? Or what can be done to stop the noise?

Thank you !

Have you checked the Ground is connected, pin 4 in the spindle, this has to have continuity to the spindle body, if not this has to be corrected, it also sounds like you have some parameters set incorrect, do you have a list of the parameters you set

Just looked at what you posted no they are not set correct I will post you a list of what you have to set, but first we have to know which VFD Drive you have

[suganesh95]

mactec54

Yes, pin 4 is connected to the ground.
VFD is a Chinese YL620-A, 2.2kW, single phase input to three phase output, 400Hz, 10A, 220V
The spindle is a Chinese 1.5kW, 24000 rpm, 400Hz, Liquid cooled spindle, 8A, 220V

For the parameters please check my post above I have uploaded a pdf file.

Aslo P 00.00 is the AC mains frequency i.e the frequency present in the wall socket plug and not the spindle frequency and here in India, it is 50Hz P 00.04 is the max. Spindle frequency.

[suganesh95]

mactec54

Ok so here's what i did. Tell me if i did right.
I used my multimeter to check if the pin 4 is connected to the body. I went about it the following way:
- First I set the multimeter to "check continuity mode i.e it beeps if the circuit is closed"
- Then i touched the red probe of the multimeter on the spindle body and the black one on the pin 4, and guess what it didnt beep, also to check i touched the black probe on the the body and this time the multimeter beeped, i checked it with the screws on the spindle and also the threaded part of the female connector on the spindle and for both the cases it beeped but not when i touched pin 4.

So, probably my spindle its not grounded. This worries me !
Is there anything that i can do about it cos i cant open the back cover of my spindle.

Thank you !

[mactec54]

mactec54

Ok so here's what i did. Tell me if i did right.
I used my multimeter to check if the pin 4 is connected to the body. I went about it the following way:
- First I set the multimeter to "check continuity mode i.e it beeps if the circuit is closed"
- Then i touched the red probe of the multimeter on the spindle body and the black one on the pin 4, and guess what it didnt beep, also to check i touched the black probe on the the body and this time the multimeter beeped, i checked it with the screws on the spindle and also the threaded part of the female connector on the spindle and for both the cases it beeped but not when i touched pin 4.

So, probably my spindle its not grounded. This worries me !
Is there anything that i can do about it cos i cant open the back cover of my spindle.

Thank you !

It is not Grounded which is very common with these spindles, it should be the first thing everyone checks when they get these spindles

It will have to be corrected, can you post a photo of the top of the spindle sometimes they stuck on with some type of glue but they will come off, blow the water out before you try to take the top off

[suganesh95]

It is not Grounded which is very common with these spindles, it should be the first thing everyone checks when they get these spindles

It will have to be corrected, can you post a photo of the top of the spindle sometimes they stuck on with some type of glue but they will come off, blow the water out before you try to take the top off

Please find attached the pics.

Can the spindle be grounded by attaching a wire to its body? Will it suffice or should the rotor shaft also be grounded along with it ?

[mactec54]

Please find attached the pics.

Can the spindle be grounded by attaching a wire to its body? Will it suffice or should the rotor shaft also be grounded along with it ?

Draining the water out remove the 4 cap screws on the top and it should come off, is that top plastic or metal most are aluminum and coated

As for Grounding outside that would be a last resort, as a wire like this can act as an antenna and emit EMI

[suganesh95]

Draining the water out remove the 4 cap screws on the top and it should come off, is that top plastic or metal most are aluminum and coated

As for Grounding outside that would be a last resort, as a wire like this can act as an antenna and emit EMI

The cap is sealed it wont come off even after removing the screws.

[KH0UJ]

Sounds like the H7000 and the H7002 angular contact ceramic ball bearings had a deep scorch since the beginning of their assembly, happens to us on one of our production spindles, DAMN those bearings cost a lot!!! the china made will cost you $45-50 a piece, the japanese NSK version $100-120, but I ended up buying the NSK 6002 that only cost $1.90 a piece, took out the covers for a more freeflow motion, washed it with gasoline to take out the internal lubrication, put some high temperature grease, now it runs so much smoother using the original NSK japan ball bearings with a fraction of the cost. haha



You can inspect the ball bearings by opening the tiny allen bolt on the inner shaft side, it`s a spring loaded (6 springs) after taking out the screws you can safely pull the motor shaft directly to inspect the bearings.

[mactec54]

Sounds like the H7000 and the H7002 angular contact ceramic ball bearings had a deep scorch since the beginning of their assembly, happens to us on one of our production spindles, DAMN those bearings cost a lot!!! the china made will cost you $45-50 a piece, the japanese NSK version $100-120, but I ended up buying the NSK 6002 that only cost $1.90 a piece, took out the covers for a more freeflow motion, washed it with gasoline to take out the internal lubrication, put some high temperature grease, now it runs so much smoother using the original NSK japan ball bearings with a fraction of the cost. haha



You can inspect the ball bearings by opening the tiny allen bolt on the inner shaft side, it`s a spring loaded (6 springs) after taking out the screws you can safely pull the motor shaft directly to inspect the bearings.

Not all these spindles are as you describe, for disassembly

He does not have a Bearing problem, he has it running as it should, there where Parameters that needed to be set that was causing the problem

[KH0UJ]

Not all these spindles are as you describe, for disassembly

He does not have a Bearing problem, he has it running as it should, there where Parameters that needed to be set that was causing the problem

Well I wish I took a video on it before disassembly, it sounds exactly like his spindle, right before entering the 24K range it starts to stutter or rattle same on his problem, I dont doubt on our controller because it`s just a plain and simple inverter with no digital calibrations on it, the speed control is just a potentiometer to vary speed, it`s worth a try to investigate, if it`s not then maybe it`s an inverter setting issue