Spindle stopping at 10,000 rpm?

[charlieuk]

I'm back having problems with a friends Chinese CNC. The spindle (1.5kw water cooled 80mm) seam to stop when I try to make it go over 10,000rpm. If I set it in fusion cam to do 10,000rm its fine however if I set it to 12,000 it does not start. If I set it to 10,000 then start the file and then up the spindle speed in nc studio it also then cuts out so I am thinking its on the vfd side of things.

I don't have much in the way of instructions for the machine so finding it hard to figure much out, any ideas? The pic bellow shows the vfd I'm not sure even what one it exactly is.

[magicniner]

I am not familiar with the VFD model, you'll need to read the manual for details, but that sounds very much like the ramp-up time is set too short and you need a slower ramp-up setting in the appropriate parameter(s)

[m_c]

I wouldn't of thought ramp up time would cause the issue, especially since it seems to get up to 10k OK.

However, we really need more details.
VFD make/model (there must be a sticker on it somewhere..), what software/controller is the machine using, and how is the VFD interfaced to the controller (0-10V or Modbus).
Any messages shown on the VFD when the spindle stops?

[charlieuk]

OK I'll have to see if I can find out more about the vfd but like with most Chinese stuff there is little to no instructions that came with it. Will unbolt it and take a look on the back when I'm back there on Monday.

The machine is running on nc studio which im only just figuring out I'm not sure what the other components are but again will try find out more on monday . many thanks

[m_c]

When you're there, try and work out a wiring diagram, and get some photos of how things are connected.

If you can work out the activation signals to the VFD, see if they remain active when the spindle stops. There is the possibility that the controller is stopping the spindle when too high a speed is commanded, so knowing what the activation signal/speed set signal are doing narrows down to if it's a controller issue, or a VFD issue.

[John S]

10,000 revs divided by 50 hz equals 200.

First check on the plate that the VFD can actually go to 400 hz, many can't. I have a couple here than can only go to 150 Hz and 200 Hz.

Then check inside the parameters for Max Hz isn't set to 200 instead of 400.