VFD Spindle control not working

I’ve read several threads on this topic as I’ve been working through a number of issues but got to the point where my 2.2kW water cooled VFD Spindle was working manually with no issues. However, once I connected the VFD to Shapeoko Controller (CarbideMotion v3.0c) I got no response using the ‘Spindle On/Spindle Off’ (Son/Soff) button but, I was getting 0.4v from the 6-Pin Moles Micro-Fit 3 connector. This signal is also getting to my VFD input connector. I did read that the Son/Soff may not work regardless?

I attempted to run my first cut but the spindle never fired up. At this point I had followed (Luke), @Julien and @Norway setup advice for the VFD but, forgot to set the Pd003 parameter to accept external control (2). That was done but the Son/Soff function is still not working?

Should I just attempt to run a cut? (Assuming Son/Soff is an isolated issue?)

This is my first time running the machine so I’m probably making a few mistakes but, If i’m getting 0.4v when Son/Soff is triggered on, I ‘should’ get spindle movement?

Woz

Hi @Woznaldo,

Assuming your VFD is setup properly for external control on a 0-5V analog input, things will work if the other end (the Shapeoko controller) is also configured properly to output 5V for max RPM and 0V for 0 RPM. This will happen if GRBL param $31 is set to 24000 (assuming 24000RPM is the max RPM of your spindle) and $30 is set to 0.

Try making a toolpath with RPM set at 12000 for example, set Z zero in the air somewhere, and run the toolpath: you should see the spindle run at about 12000 RPM and output voltage close to 2.5V

I lost track of which version of CM has the spindle on/off button working, but you should not need it anyway if your VFD and GRBL params are set correctly

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Hi Julien, thanks for the response. I have only used the Carbide Motion ‘Machine Setup’ wizard and selected VFD Spindle. I’m not sure, although read some references, what GRBL is and how I confirm whether it is set correctly?

I can run a toolpath with a ‘safe zero’ and see what happens but, the GRBL setup may be the step I’ve missed?

Is this thread what you are referring too? Setting up vfd, rpm

Woz

Hi Woz,

“GRBL” is the software that runs under the hood on the Shapeoko controller. It has a number of configuration parameters, named “$[some number]”, and they can be adjusted from a command shell. There is normally no reason to know about GRBL or to go and tweak those parameters since Carbide Motion does that for you when running the setup wizard, but when you setup a third-party VFD/spindle, that is one case where you may need to go and adjust/check parameter value.

By the way apologies for typing in the wrong $ number for max RPM in my post above, this is $30 not $31 (I always mix those two). Do follow the instructions from that thread you linked, and you should be able to confirm whether $30 value is correctly set to 24000, which is really all that matters. And run that air cut to confirm before doing a real cut.

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I ran a safe zero toolpath and got no spindle response. I will next try to verify PWM output for given GRBL commands i.e. 12000 =2.5v and 24000 = 5.0v

I went into GRBL and my settings are as follows:

$$
$0=10
$1=255
$2=0
$3=5
$4=0
$5=0
$6=0
$10=255
$11=0.020
$12=0.010
$13=0
$20=0
$21=0
$22=1
$23=0
$24=100.000
$25=2000.000
$26=25
$27=3.000
$30=24000 <<this looks correct?
$31=0
$32=0
$100=40.000
$101=40.000
$102=320.000
$110=10000.000
$111=10000.000
$112=1300.000
$120=500.000
$121=500.000
$122=100.000
$130=845.000
$131=850.000
$132=150.000
ok
N0G4P0.5
ok
$xG92.1G49G10L2P1X0Y0Z0G54G21G90
ok

Yes it looks fine, you should be good to go!
(assuming the VFD is setup correctly to map 0-5V input to 0-24000 RPM)

I’ll check VFD setup again and map the PWM output.

Pd002 - (0, 1, 2) - What controls the VFD. In Luke’s resource he states (2) is PWM control. I’ve tried all options but, still no joy.

I’m hoping the VFD is working correctly. It works perfectly in manual mode, which allows me to make some chips/dust.

Woz

What’s the brand/reference of your VFD?

It’s a 2.2kW 220v HY, water cooled.

You may or may not have seen that thread :

You can double-check what each of your VFD settings currently is.
On my HY model, the PD002 need to be set to “1” (not 2) to enable external control, but do check your specific model’s user manual to be sure.

If manual control is ok at the VFD, if PWM voltage is properly varying from 0 to 5V depending on the commanded RPM and making its way to the VI pin of the VFD, and if your spindle is still not operating, maybe double-check if you have a VI/VR jumper on the VFD, as shown in the last picture of this post:

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Julien, thanks for your support with this issue. This is very much what the community should be about. Hopefully I can pay it back sometime.

I will go through the checks and report back when complete.

Thanks again.

Woz

I thought I’d found the issue (with Juliens’s advice). The VI/VR jumper was incorrect but, nothing changed after correcting it? I did try different Pd002 settings 1 and 2 (I will go back and try 0 for completeness too). I’ve yet to map PWM output or check full spectrum of parameters.

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Lots to report! When I ran through the PWM checks I found the signal intermittent. A flex of the wire near a connector (one I fitted for an eventual enclosure) found the source of the problem. I chopped 30mm off the end and re-terminated and I got a consistent signal as follows:

/M3S6000 = 1.311v
/M3S12000 = 2.533v
/M3S18000 = 3.700v
/M3S24000 = 4.901v

The issue I have now relates to another setting on the VFD. The M5 (off) function just reduces the speed to minimum (6000 rpm). Unsurprisingly, I set Pd003 to 0 but, it had no effect due to Pd002 set to 1 (not 0).

Pd011 was set to 100 (now changed to 0), which was the problem. The spindle now fires up on demand and the first wood chips have been cut! The speeds reported on the VFD seem to be a little high Carbide Create tool speed was 18109

I now have to find a quiet dust collection system. I bought a small cheap wet/dry vacuum and it’s piercingly loud! Undoes the quiet running of the spindle!!

Many thanks to Julien for his assistance with this (these) issues.

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You might consider the shop vac discussed here. I’ve had it for nearly a year and it’s been amazing.

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