[ger21]

I have a video on Youtube that I did last year. The voltage reading on the meter does not change at all, and the RPM will constantly fluctuate, +1000, then -1000. As I said, it takes over 30 seconds for the 2000rpm change, and the voltage is steady the entire time.

[OlfCNC]

30 seconds is a long time. It is likely a VFD problem. But it is also possible that the carrier frequency of the PWM is close the same as the VFD sampling frequency and is a high frequency.
If the frequency is high the multimeter will not show the fluctation.
The VFD is measuring in periods and that always shift only a little bit on the PWM so the measured sum voltage and the RPM changes slowly as the measurement slowly walks through the PWM period.
Without measuring it with an oscilloscope this will remain only a theory though.
Another thing to try is to change the PWM frequency to see if it makes any difference but that will also likely to give results which could not lead to a final consequence.

[Tyknok]

If the voltage is stable on the analog input of the VFD and the motor RPM is fluctating then the problem is with the VFD, but there is one question that the voltage is really stable?
How did you measure it? With a multi meter or with an oscilloscope?

I measured it with a voltmeter.

[ger21]

The breakout board converts the PWM to the 0-10V, so the VFD never sees the PWM signal?

[OlfCNC]

The breakout board converts the PWM to the 0-10V, so the VFD never sees the PWM signal?

Yes but how well does it convert the PWM?

[ger21]

If the multi meter says the voltage is stable, and never changes at all, doesn't that mean it's pretty good?
My voltage was always accurate to within .01 volts, at any rpm range, and was 100% stable. But the RPM was never stable.

[OlfCNC]

No, because the multimeter shows only one value which is based on measuring a period of time and avaraging that and the time is usually long.
You can have for example a PWM with 50% dutycyle 0-5 Volts and high frequency which your multimeter will show as a 2.5V DC voltage, because it samples and avarages.
In regards the analog voltage for the VFD it is possible that the breakout board converts the PWM to analog inperfectly leaving some fluctation on the signal, for example a 4.5V signal with a 1Vpp fluctation on it.
If the frequency of that fluctation is high enough then your multimeter might not show it to you, but an oscilloscope is.

[Tyknok]

Hi All of you

Just to inform you, I purchased a new VFD, it was completely plug and play, I did the settings, and ran UCCNC with the allready configured plugin, the spindle rotates rock solid at all given RPM settings.
Thank you all for your support, and a special thumps up for Dan for making this awsome plugin.

Regards
Jan

[Dan911]

Hi All of you

Just to inform you, I purchased a new VFD, it was completely plug and play, I did the settings, and ran UCCNC with the allready configured plugin, the spindle rotates rock solid at all given RPM settings.
Thank you all for your support, and a special thumps up for Dan for making this awsome plugin.

Regards
Jan

Hi Jan,

Your update is very appreciated but unfortunate China stuck you with a bad VFD. I'm sure very little conciliation to you but your bad experience read here can help others.

Thanks,
Dan

[gene8522]

Hi Dan911,
PM Sent.

[Regulator]

Hi Dan great plugin and thanks for all your hard work, I have it running in uccnc and the 2017 Screen set. I do have 1 question and that is when I increase my speed with either the plus symbol or the slider it maxes out at 18000, my max is set to 24000 for a 2.2kw water cooled spindle. I can s command it to 24000 and it goes there so I'm just wondering if that's normal. Thanks in advance!

Best Regards,
Bob

[gene8522]

Hi Dan great plugin and thanks for all your hard work, I have it running in uccnc and the 2017 Screen set. I do have 1 question and that is when I increase my speed with either the plus symbol or the slider it maxes out at 18000, my max is set to 24000 for a 2.2kw water cooled spindle. I can s command it to 24000 and it goes there so I'm just wondering if that's normal. Thanks in advance!

Best Regards,

Bob

Go to "CONFIGURATION/AXIS SETUP/SPINDLE" and check "PWM Spindle". Be sure to check "port & pin" settings.

[Regulator]

Hi gene8522, I'm not sure what to pick as far as port and pins, I'm using the JBtec I think that's the right name, it's the usb ger21 recommends. If I managed to miss something that I was supposed to enter please let me know. Thanks for the reply

Best Regard,
Bob

[Jckhmmr]

Hi Dan

Is it possible to add a safety function to your plugin?
At the moment it's seems that you don't check for a feedback afterwards you have send a command.

For example if the VFD is off and you start a job, the plugin will just send the run command and assume that all is fine which could lead to some damage.

I don’t know if the VFD sends a received feedback on all the commands but otherwise you can ask for the actual RPM or the frequency directly after the run command,
if there is no feedback after 500-1000ms it will trigger an e-stop and maybe show a msgbox.

What do you think?

// Jack

[Dan911]

Yes, the VFD responds to every command. I can have plugin monitor the Status and if cycle start is pressed and VFD not responding..."Do Something"

Let me put a little thought into this to make sure this wouldn't cause more problems than good.

Dan

[Dan911]

Hi Dan

Is it possible to add a safety function to your plugin?
At the moment it's seems that you don't check for a feedback afterwards you have send a command.

For example if the VFD is off and you start a job, the plugin will just send the run command and assume that all is fine which could lead to some damage.

I don’t know if the VFD sends a received feedback on all the commands but otherwise you can ask for the actual RPM or the frequency directly after the run command,
if there is no feedback after 500-1000ms it will trigger an e-stop and maybe show a msgbox.

What do you think?

// Jack

Hi Jack,

Sorry long day and didn't have much time to play with this but have and idea for you to test, it would be something similar if implemented in plugin.

1. Create a field and use the Amp feature in plugin.
2. Create a Macro and input code below and use Macroloop Config in UCCNC and check Autorun.

if cycle start is pressed and VFD not responding it will trip a Estop. NOT TESTED.

bool run = AS3.GetLED(19);
bool dwell = AS3.GetLED(21);
double VFDonoroff = AS3.Getfielddouble(????);//your amp field replaced with question marks

if((run == true) && (dwell == false) && (VFDonoroff <= 0))
{AS3.Switchbutton(true, 144);}

Let me know how it works!
Dan

[Jckhmmr]

Hi Jack,

Sorry long day and didn't have much time to play with this but have and idea for you to test, it would be something similar if implemented in plugin.

1. Create a field and use the Amp feature in plugin.
2. Create a Macro and input code below and use Macroloop Config in UCCNC and check Autorun.

if cycle start is pressed and VFD not responding it will trip a Estop. NOT TESTED.

bool run = AS3.GetLED(19);
bool dwell = AS3.GetLED(21);
double VFDonoroff = AS3.Getfielddouble(????);//your amp field replaced with question marks

if((run == true) && (dwell == false) && (VFDonoroff <= 0))
{AS3.Switchbutton(true, 144);}

Let me know how it works!
Dan

Hi Dan

Nice, but I think that a delay is needed.

When you press cycle start it normally takes some seconds before the g-code start the VFD, and then its takes some time before you getting an AMP reading.

I change the input to "SpindleCW enable" instead of "Cycle Start".
and then a delay before I tried to read the AMP value

something like this:

bool SpindleCW = AS3.GetLED(50);
bool state = false;
double VFDamp = AS3.Getfielddouble(998);//your amp field replaced with question marks

if((SpindleCW == true) && (state == false))
{
	Thread.Sleep(2000);

	if(VFDamp <= 0)
	{
		MessageBox.Show("Communication Error");
		AS3.Switchbutton(true, 144);
	}
		else
	{
		MessageBox.Show("OK");
	}

	state = true;

}

if(SpindleCW == false)
{
    state = false;
}

it's not working perfectly, and a don't know if Thread.Sleep() it the best thing to use.
I will keep playing with this later this week.

Thanks
// Jack

[Dan911]

Hi Jack,

UCCNC has a M3, M4 delay setting (Dwell) for when Cycle Start is pressed, this is to make sure your spindle gets to proper RPM before it starts cutting. I included this check in macro I posted so to ensure Amp field had a reading.

Go to CONFIGURATION / AXIS SETUP / SPINDLE and set a delay for M3 and M4.

Dan

[Al_The_Man]

I have not followed this thread in any depth but on this subject it should be possible to read an input from a VFD output that sets an output to At-Speed or Up-to-Speed.
This holds off any further commands until the input is seen.
This is the way the Fanuc's and Mits etc do it.
Al.

[OlfCNC]

I have not followed this thread in any depth but on this subject it should be possible to read an input from a VFD output that sets an output to At-Speed or Up-to-Speed.
This holds off any further commands until the input is seen.
This is the way the Fanuc's and Mits etc do it.
Al.

Do you think that this cheap chinese spindle has the same features as a spindle in a Fanuc machine? I don't think so. These spindles do not even talk modbus properly, this is why this plugin is needed. otherwise uccnc has a modbus plugin which could be used.