[shock-cnc]

So I decided to make a video on how to program / wire the nowforever VFD that comes with most Chinese CNC machines. Hope this helps someone in need of this information in the future.

https://youtu.be/lncconN83G4

[mactec54]

shock-cnc

What are the spindle spec's, you are running

[shock-cnc]

1.5kw spindle
0-24000 RPM
ER11

[mactec54]

1.5kw spindle
0-24000 RPM
ER11

Where did you find a 0-24000 RPM spindle

[shock-cnc]

It came with my CNC 6040 machine. You can easily purchase one from ebay for example this is similar to the one I have - 1 5KW Water Cooled CNC Engraving Spindle Motor ER11 220VAC 5A 24000rpm 3 Bearing | eBay

[javanree]

Something to definitely also do if you've got the case open : earth your VFD !
The E terminal on the lowest level is for earthing your VFD. A with all Chinese electronics, their grounding is a mess...

I've chosen the ground point at the power filter as my central grounding point and from there I ran ground wires directly to the VFD (terminal E), to the 24V stepper PSU and to the spindle.

[shock-cnc]

Thanks for the tip I am going to do this right now! Cheers!

[mactec54]

It came with my CNC 6040 machine. You can easily purchase one from ebay for example this is similar to the one I have - 1 5KW Water Cooled CNC Engraving Spindle Motor ER11 220VAC 5A 24000rpm 3 Bearing | eBay

Yes if that was only correct, they do not have a zero to 24,000 RPM, your Minimum Frequency must be set to 100 Hz, there is nothing in your programing that should relate to 50 Hz, for safety until you know if your spindle is good or not, 120 Hz for the Minimum Frequency is the safest bet

Grounding, you need to check the 4 th pin in the spindle connector, to make sure it is connected, then your Ground wire goes from your Spindle to your VFD, then your VFD to the input Power Ground, this is important for safe use of these machines, you will connect all Grounds to this same point, ( Star Ground )

The Ground wire in the on most of these Spindles is not connected, the same with the VFD Drives also, this is very dangerous to operate without this being corrected

[shock-cnc]

Yes if that was only correct, they do not have a zero to 24,000 RPM, your Minimum Frequency must be set to 100 Hz, there is nothing in your programing that should relate to 50 Hz, for safety until you know if your spindle is good or not, 120 Hz for the Minimum Frequency is the safest bet

Grounding, you need to check the 4 th pin in the spindle connector, to make sure it is connected, then your Ground wire goes from your Spindle to your VFD, then your VFD to the input Power Ground, this is important for safe use of these machines, you will connect all Grounds to this same point, ( Star Ground )

The Ground wire in the on most of these Spindles is not connected, the same with the VFD Drives also, this is very dangerous to operate without this being corrected

I thought that was where you were going with this (the 0 - 24000hz) quesiton. Although it could be argued that it does indeed function as expected at 0hz (i.e. stopped) the inbetween is not as some would expect and as you described perfectly. You are indeed correct. Although this is not really the focus or point of the video, it is excellent information to share and I do appreciate it. Also, the 50hz setting was the default on the VFD not a setting I recommended. Could you ellaborate on what you mean by "knowing if your spindle is good or not"?. Also could you elaborate on the dangers of using the spindle ungrounded as it is?

Cheers

[Al_The_Man]

Also could you elaborate on the dangers of using the spindle ungrounded as it is?

Cheers

A couple of reasons, safety per NEC/CEC, and also you can certainly be in for spurious noise issues, false tripping of limits sensed etc.
http://www.cnczone.com/forums/phase-...se-issues.html
Al.

[shock-cnc]

A couple of reasons, safety per NEC/CEC, and also you can certainly be in for spurious noise issues, false tripping of limits sensed etc.
http://www.cnczone.com/forums/phase-...se-issues.html
Al.

Thanks for the reply Al. Although I haven't noticed any noise issues (i.e. limit/home switches work fine etc...) perhaps it is just because I haven't been looking for it or perhaps because I am using an usb motion controller and not a parallel port (I will never go back to using a parallel port after seeing the performance increase of using USB). I will make a video of grounding the spindle and VFD and do a before and after to see if I notice any difference in the operation of the spindle and the machine itself. Do you know if there is a danger of electrocution by not having the spindle grounded? When people say there is a huge safety issue by not grounding the spindle I am assuming this is what is meant by that?

Cheers

[mactec54]

shock-cnc

These Spindles are known to burn up with in correct VFD settings, sometimes it is the VFD that will be damaged, the VFD you are using is a little better than some that others have, so in you case the spindle will be damaged, burned up first with the incorrect VFD settings, with a good VFD 100 Hz is your minimum setting for this type of spindle, Default settings don't count, they have to be changed, the VFD default settings are for a regular AC 50 Hz motor, not 400Hz Spindles like these

You may not notice any difference by putting Ground wires where they need to be,They are for your protection, without them and your Spindle or VFD fails, there is no protection for the machine or the user

[shock-cnc]

shock-cnc

These Spindles are known to burn up with in correct VFD settings, sometimes it is the VFD that will be damaged, the VFD you are using is a little better than some that others have, so in you case the spindle will be damaged, burned up first with the incorrect VFD settings, with a good VFD 100 Hz is your minimum setting for this type of spindle, Default settings don't count, they have to be changed, the VFD default settings are for a regular AC 50 Hz motor, not 400Hz Spindles like these

You may not notice any difference by putting Ground wires where they need to be,They are for your protection, without them and your Spindle or VFD fails, there is no protection for the machine or the user

Thanks for your reply Mactec54. I just want to be clear on something: Are you saying that running this spindle at 50hz (i.e. approx. 3000 RPM) in the air (not cutting) is going to damage this spindle? If so can you explain why it will be damaged?

Cheers

[mactec54]

Thanks for your reply Mactec54. I just want to be clear on something: Are you saying that running this spindle at 50hz (i.e. approx. 3000 RPM) in the air (not cutting) is going to damage this spindle? If so can you explain why it will be damaged?

Because the Spindle is not designed to run that slow, it will overheat, if left long enough you will get to see smoke, the other problem is if you program your speed wrong and it starts to cut a part, at a low speed you will have instant stall followed by a burned out Spindle

Here is a snippet from another thread, When I made it run on 50hz it started to smoke and got hot very quickly, there are many post around different forums with this same information, this is not a new problem that users try to use VFD default settings, all VFD Drives default to either 50Hz or 60Hz, everyone must program there VFD to suit their Spindle or Motor spec's

[Al_The_Man]

If so can you explain why it will be damaged?

Cheers

If you notice these motors are small compared to their 50/60Hz versions, this small frame/core size results in a lower inductance value (Mh), inductive reactance (Ohms) increases with frequency, IOW at low frequency the inductive reactance is lower than their heavier cousins resulting in high/excessive current.
Al.

[slaith]

I actually read about some guy who modified his torque curve in the VFD to be able to run 3000rpm, thereby not having to mill at fast feeds.
Apparently it worked really well, the only thing was that it got really hot, but he had proper cooling and it worked just fine.

But you have to give it som good amps to up the power in the lower rpm:s.

[Al_The_Man]

But you have to give it som good amps to up the power in the lower rpm:s.

Current (amps) = Heat!
Al.

[shock-cnc]

Thanks guys for the important information. I will be making another video regarding the VFD and grounding. I will be sure to include a note regarding spindle speed as well in the video. This place is such a wealth of knowledge and it is due to people such as yourselves that help make the learning curve a little less steep for us hobbyists. Thanks for steering me in the right direction!

Cheers

[mactec54]

shock-cnc

This thread will also give you a lot of information about these spindles and VFD Drives, this is mainly about a different VFD, but is used on a lot of these same Routers, the same thing applies no matter what the VFD brand name is, better quality VFD Drives can withstand some wrong settings, but then down the road the Spindle will suffer,

http://www.cnczone.com/forums/spindl...gs-manual.html

[Nleo22]

How do you guys setup for mach3 to read rpm automaticly ?? I have 6040z usb 1500watt, on mid "m3 s7700" I get spindle to run at 400hz but on the rpm section show at Zero?? I try to add hall effect sensor but I don't see anywhere to mount on. Anyone have suggested to let mach3 read rpm automatic without hall sensor?