Messages

11

General Mach Discussion / Re: Initial Speed control issue

« on: June 01, 2014, 08:34:47 AM »

Same bug documented here!

http://www.cjh.com.au/PWM%20Spindle%20Control%20using%20Mach3.pdf

12

General Mach Discussion / Re: Initial Speed control issue

« on: June 01, 2014, 08:28:02 AM »

OK,
I will rephrase the issue.

Remember this is PWM control, not pulse frequency via steps, so the motor tuning is not relevant. Proved this by setting all the values for spindle to zero. The relevant control for PWM are in the spindle setup tab:- motor control  ( step and dir NOT ticked, PWM freq 1000 and 5% min) and special features ( ticked feedback in sync and Averaging) as you have seen in the XML.

From cold start or from a reset, MDI a S word  "n"  ( where n= 500-2000, just happens to be limit of tests)
start spindle from screen button or a M3/M4 ( this is slant lathe so turn in reverse)
Spindle rotates at approx. 120-125% above set speed, speed stable at this speed ( if you implement the PID feature then speed will slowly crawl down to setting, but there are other issues with PID control and so are advised to not enable.)
do another S word and Mach 3 reads correctly the speed and spindle revolves at calibrated revs for that speed.  ( PWM control is  not infinitely variable, integer frequencies,  so will work at nearest speed which normally within 20 rpm)

(to clear the other red herring :IF you forget to reset the OV% then you can get jump to max speed, which I clarified and have now instated in my start up sequence.)

I have seen mention of this limitation, but have failed of later to track the thread and/or any fix, other than writing programs that double issue the speed at the start of the programme after spindle live.

Hope now clarified?

13

General Mach Discussion / Re: Initial Speed control issue

« on: May 31, 2014, 04:05:38 PM »

Yes I use the charge pump, but only into the BOB.
Pins on that drive a digispeed board which gives the 0-10v to the VFD invertor. The volts for that from the VFD.

so I would tend to input something like this first time you run the spindle, remembering to clear out any spindle over OV% increment, so it is not that.
S750
M3   : at which point motor will hit around a 1000 rpm
S750 : and speed reduces to within 20 rpm
M5
next time you run it tracks oK

From then on it hits the calibrated curve OK.


Good linearity of control

14

Modbus / Re: Homann Modio config error

« on: May 31, 2014, 03:36:52 PM »

Peter,
Mike gave Up on the Lathe and I now own it, long story.

Now wish to finish the conversion. 
 Your comments above very useful and spent last 48Hrs on a step learning curve of Brain and Modio, having just used vanilla Mach3 for the last 8? years
Register 1155 appears to give no valid outputs. The MPG works, the LEDs work but reading the register from the test shows a fixed value, normally 0000 or FFFF so assume the chip is partially fried?  A quick check proves most of the other pins are OK. Is there any other possibility?  If not I assume it is buy a new board or live without a second MPG?

Regards Peter

15

General Mach Discussion / Re: Initial Speed control issue

« on: May 31, 2014, 08:42:24 AM »

XML attached.

Seems to be more of a problem of reading the initial setting that that of set-up, but be interested if you see any issues in it.

16

General Mach Discussion / Initial Speed control issue

« on: May 30, 2014, 08:25:23 AM »

Hi,
Have a lathe with VFD drive running via PWM.
When initially launch Mach3 and after an S command M3 or M4 drive motor at max revs. Reissuing S and then M5 then M3 or M4 bring it back under proper control.
Assume this is a known bug, what is the fix?

17

Sieg Machines / Re: x3 Mill Homing Switch Install Question

« on: May 30, 2014, 08:00:46 AM »

Did you get an answer?
If not I can help.
How much more travel do you need? what is total travel?

18

VB and the development of wizards / Re: Modifying lathe wizards

« on: August 13, 2010, 06:13:09 AM »

Good thinking butjavascript:void(0);, When I said "in effect", it actually is a rear turret. There is NO front tool post. The action of the Reversed Arc's is what I want, on the rear tool post. ( Boxford 160TCL with 8 station turret)

Was starting to think if I configured it as if it was actually a front tool post, but would need to swap the z axis polarity etc, re hand the cutting tools etc.

And would still have to correct the spindle rotation direction, hence me wanting to swap lines in the wizard code. Else I just write a batch file to automate the process of swapping in the wizard output.

Peter

19

VB and the development of wizards / Modifying lathe wizards

« on: August 12, 2010, 10:10:01 AM »

Hi,
is there an easy way to modify the turning wizard? I run a slant bed lathe with in effect a rear turret. So have to edit the output of the wizard, change G02 for G03 and M3 for M4 and vis versa,

If not an easy way will a copy of visual studio 2002 do the job rather than 2003?

Regards