Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing - Question about using a rotary table
One thing which does need addressing is that, whatever solution is found ( and I suspect that we may actually be approaching a consensus on what is required...). the rotary axis/axes need to be able to home either to the position in which they currently are or to the nearest '0' when EMC2 is first switched on. It will be no use having a system where, if the last job you did was milling a 12 length of 40 thread, hitting the home button will cause the rotary to set off on an interminable unwind.. Some while ago I got used to running a short script of G54, G92.1, G10 etc. to reset the home position of the axes as they were starting in 'random' positions but the later versions of EMC have sorted that problem and homing is now easy. However, as EMC will not now allow any operation without all the axes being homed first, optionally running such as 'position setting' script before a rotary sets off on a long unwind is not now possible. Ian ___ Ian W. Wright Sheffield UK -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing - Question about using a rotary table
On Sat, 03 Oct 2009 08:54:25 +0100, you wrote: However, as EMC will not now allow any operation without all the axes being homed first, optionally running such as 'position setting' script before a rotary sets off on a long unwind is not now possible. Hi Ian, put NO_FORCE_HOMING=1 in the [TRAJ] section of your ini file, that cancels out the nanny state homing, you can still home after if you wish G. Steve Blackmore -- -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing
On Fri, 2 Oct 2009 22:32:02 +0100, you wrote: 2009/10/2 Chris Radek ch...@timeguy.com: Also as Andy pointed out, you can do an optional short move to zero in some controllers, invent a code for it if considered essential. OK, I agree a counterproposal might have this scheme. G1.1 and G0.1 ? Take the shortest route and reset the machine coordinates to match the relative ones. (I am not sure about that last bit, but I think it makes sense) I agree there should be another code, perhaps not G0.1 or G1.1 Something like G28.2 or G30.2 would be nearer to the function. It definitely shouldn't reset the co-ords unless specifically told to do so using G91.1 or G92.2 Steve Blackmore -- -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing - Question about using a rotary table
You can disable that feature if you wish. http://www.linuxcnc.org/docview/html//config_ini_config.html#sub:[TRAJ]-section John On 3 Oct 2009 at 8:54, Ian W. Wright wrote: problem and homing is now easy. However, as EMC will not now allow any operation without all the axes being homed first, optionally running such as 'position setting' script before a rotary sets off on a long unwind is not now possible. Ian ___ Ian W. Wright Sheffield UK -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing - Question about using a rotary table
2009/10/3 Ian W. Wright watchma...@talktalk.net: It will be no use having a system where, if the last job you did was milling a 12 length of 40 thread, hitting the home button will cause the rotary to set off on an interminable unwind.. A rotary axis will only ever home to the home switch, and it is hard to think of a way that could ever be more than 360 degrees away. I think that if it was at 40 turns + 10 degrees it would unwind 10 degrees, see the switch, and zero-out the 40 full turns in the machine coordinates. How many rotary axes actually have home switches anyway? I am embarassed to say that I have never noticed if EMC holds relative position information during a power-down, or machine position for that matter. -- atp -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Advice for mesa 5i20 servo drivers needed
I got triggered by the mail from Klemen about his servo amplifiers. I own a 5i20 card, currently it is controlling my EMC mill using stepper motors. A conversion towards servo motors is on its way - the servos have been ordered (both 1.7 and 2.5 Nm versions to play with). The question now is what kind of servo drivers to use? I am looking at the 7i40 or 7i27 cards from Mesa electronics but the 7i27 is too small for the larger motor (60V motor where the 7i27 only goes up to 40V). I did not look at the 7i33 that Klemen used - this could also be an option. What is the way to go? PWM controlled servo drivers or analogue, go for the 7i40 or use the 7i33 (0-10V interface) with analogue servo amplifiers (and what kind of) ? The motors are brush type servo motors, the small motors are 48V 3.5A and the larger one is 60V 4.5A but these are nominal currents. My current best guess is that the 7i40 is a good card for the job and with 2 channels per card (of 149 USD) not expensive. Another card is the card from Pico Systems and with 20A it can deliver a higher current but this comes with a price (125 USD per channel). But ... the 7i40 HV version only goes up to 7A and the smaller motor specifies a max. current of 24A. So the big question is if the 7i40 is enough or should I spend more money on the Pico Systems PWM Servo amps or should I even go for another solution? Unfortunately the motors are still in the mail - as soon as these arrive I'll be testing them to see what the real power requirements are. Any input is greatly appreciated. Regards, Rob -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing - Question about using a rotary table
I am embarassed to say that I have never noticed if EMC holds relative position information during a power-down, or machine position for that matter. Only when you use the position_file option POSITION_FILE = position.txt If set to a non-empty value, the joint positions are stored between runs in this file. This allows the machine to start with the same coordinates it had on shutdown. This assumes there was no movement of the machine while powered off. If unset, joint positions are not stored and will begin at 0 each time EMC is started. This can help on smaller machines without home switches but this should not be used as a switch on and go option as EMC still has no way of knowing where u are from swithc off to switch on, unless your reading absolute encoders etc but then u would't need the position_file ;) -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] WG: Re: WG: Re: axis and batch processing
Chris, I've managed to get a preview that seemed to display a combination of the files. Set the PROGRAM_PREFIX setting in the ini file to the location of the called files Removed the M30 codes from the end of each sub. regards, Jan On Thu, Oct 1, 2009 at 12:54, Chris Epicier seuch...@yahoo.de wrote: Hi all I am in the process of cutting parts, due out soon. Should be doing million things, other than keepin my cnc busy. I checked and rechecked the syntax in bot, master, labels and other files. I cannot find a mistake there. Is there a way I can debug this? A way to set axis/emc to talk to me about what is going wrong? Greets chris Besides: had yesterday a couple of guys couriuos abut the cnc cutting. one of them works for steel cutter. He said he was impressed about the features and easiness emc and axis can be handled. Also my finding: great! So a big faaa thankyou to all that made emc what it is now! Jan Thank you very much for the quick reply. Stephen had pointed me to this also, I have amended the files accordingly and still get Bad Number Format. I attach the original files not stripped. Maybe there is something there that shoudl not be. Besides, all files rune smoothly as truely standa alone files. So I do not believe it is actually within the sub files. greets chris Betreff: Re: [Emc-users] WG: Re: axis and batch processing An: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Datum: Mittwoch, 30. September 2009, 19:48 Chris, in file labels.ngc, line 1: Olabels sub Should be: Olabels sub and: Olabels endsub Should be Olabels endsub This syntax error should also be corrected in the other files. regards, Jan On Wed, Sep 30, 2009 at 18:00, Chris Epicier seuch...@yahoo.de wrote: Dear Stephen Check this chapter in the manual: http://linuxcnc.org/docs/2.3/html/gcode_main.html#r3_7 Regards, Jan I did, but I just cannot get it to work. I have 5 files: [master.ngc] Olabels call Ointernal_contours call Oexternal_contours_rough call Oexternal_contours_finish call G53 G0 X0Y0Z0 [end of master.ngc] [labels.ngc] Olabels sub N0G20M6T2 N868M09 N869M30 Olabels endsub M2 [end of labels.ngc] [internal_contours.ngc] Ointernal_contours sub N0G20M6T2 N868M09 N869M30 Ointernal_contours endsub M2 [end of internal_contours.ngc] [external_contours_rough.ngc] Oexternal_contours_rough sub N0G20M6T2 N868M09 N869M30 Oexternal_contours_rough endsub M2 [end of external_contours_rough.ngc] [external_contours_finish.ngc] Oexternal_contours_finish sub N0G20M6T2 N868M09 N869M30 Oexternal_contours_finish endsub M2 [end of external_contours_finish.ngc] All files are in the same directory. I believe I got the master file about right. What I doubt there is if the homing sequence is correct but that's not a showstopper. In [labels.ngc] and all the other sub files, I doubt the missing line numbering. My programming experience tells me, either it has to be ther or totally omitted. If I load master ngc in axis, I get no errormessage. when I run the file I get Bad Number Format. I am lost now. What's wrong and where, any help is greatly appreciated. greets chris === 3.7 Calling Files To call a file name the file the same as your call and include a sub and endsub. The file must be in the directory pointed to by PROGRAM_PREFIX omyfile call (a named file) or o123 call (a number file) In the called file include the oxxx sub and endsub and the file must be a valid file myfile.ngc omyfile sub ... omyfile endsub M2 If I interprete that correctly, I shoud be able to do this: Let's assume I have these files: engrave.ngc, bevel.ngc, inner.ngc, outer. ngc, home.ngc I so, I woul generate another file, let's call it master.ngc with about te following content: omaster.ngc call engrave.ngc omaster.ngc call home.ngc omaster.ngc call bevel.ngc omaster.ngc call home.ngc omaster.ngc call inner.ngc omaster.ngc call home.ngc omaster.ngc call outer. ngc omaster.ngc call home.ngc However that fails, why? I haven't tried it, but one thing to note is that the
[Emc-users] Parameter list
Thanks I was hoping there were more to work with other than the few simple fixture values listed. I was hoping EMC was more fanuc like in nature where you can access most of the internal system parameters through macroB programing. Thanks (;-) TP -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Parameter list
2009/10/3 VMAXEmbarq vmax...@embarqmail.com: I was hoping EMC was more fanuc like in nature where you can access most of the internal system parameters through macroB programing. It would be nice wouldn't it? Of course in an open project like this, all things are possible. -- atp -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
Note also, that if the pullup that's already there is very weak, the rise time would be slowed down, but the fall time would be fast. This could produce what we see in the encoder-a trace. The 1k pullups might bring that trace closer to 50% duty cycle. . I would think a 1 K Ohm resistor from +5 V to the A and B would make a big difference. You can get +5 V from the game port or a hard drive plug. Yup, also looking closer, I see COORDINATED spikes in both A and B on a number of cycles. That reinforces my suspicion of the above. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] PWM tuning with hostmot2 and 7i33
Hi all.
I did not want to hijack the Advice for mesa 5i20 servo drivers needed
thread, but this thread may cover some of the same issues. I am having two
issues, the first I think is minor, the second I am not so sure.
1 When I try to run Setting | Calibration from tkemc, or the equivalent
under axis I get an error of the form:
af: 0 .main.top.fpage0
(followed by 4 lines starting with the same text)
Error in startup script: Invalid argument
While executing
hal getp {hm2_[HOSTMOT2](BOARD).0.encoder.00.scale}
(eval body line 1)
evoked from within
eval hal $args
etc.
If it matters, I am still running 2.3.0 as I am using the smp packages, and
have not updated them to the subsequent minor releases.
2 Tuning the servo motors
I am using the 7i43 Anything I/O card with the 7i33 quad analog servo
interface.
I am having a devil of a time getting anything close to smooth motion from
the motors in the PID tuning. I start, as I usually do by bringing up P, but
I start to get oscillations with a P value of about 20. If I use this value
to have it move to a position, it will over or undershoot the position by
1/2 (2500 encoder counts or 6/10ths of a turn of the motor shaft). The
motor is not coupled to the load at this point. Increasing P to about 160
stiffens it up to the point where one would think it would get within an
encoder count or two of the demanded position, however there is still a
strong oscillation of about +/- 0.1 (500 encoder counts or roughly 1/10th
turn of the motor shaft).
I then try bringing up I and D, but it is generally making little difference
until the values are large enough that it makes it worse. The basic problem
is that it is so bad I am having trouble even establishing a starting point
from which it will get better or worse. This is a retrofit of a system which
previously used a Galil 1800 series motion controller, and where tuning with
that system was no big deal. Galil does have a rather nice piece of tuning
software, but I don't recall even needing that.
Additionally, about six months ago I replaced an EMC system using the VTI
board (plus a 5i20 which only drove the laser) to use exclusively the 5i20
and 7i33 with the hostmot2 drivers. With the VTI card, tuning was a snap
because it ran smoothly for a large range of PID values. When I switched it
over to the 5i20, I again had a devil of a time getting it tuned, but
finally got something reasonably acceptable, but never as good as when using
the VTI board. It will still occasionally hum at idle for example, which
never happened under the previous configuration.
At the time, I thought it might be due to the PWM frequency, which I had to
set to 25Khz, as that was the maximum frequency acceptable to the laser.
With this configuration, there is no laser, so I have pwm_frequency set to
193Khz and pdm_frequency set to 6Mhz.
I keep thinking it is some value other than the PID values which is throwing
me, but so far I do not see it. I have included the relevant sections of the
ini and hal files for the axis I am trying to tune below.
-ini file-
[AXIS_1]
TYPE =LINEAR
HOME =0.000
MAX_VELOCITY = 10.0
MAX_ACCELERATION = 40.0
BACKLASH = 0.000
INPUT_SCALE =-
OUTPUT_SCALE =1.000
OUTPUT_OFFSET = 0.0
MIN_LIMIT = 0.0
MAX_LIMIT =180.0
FERROR =100.0
MIN_FERROR = 0.4
HOME_OFFSET =0.10
HOME_SEARCH_VEL = 0.10
HOME_LATCH_VEL = -0.01
HOME_USE_INDEX = NO
HOME_IGNORE_LIMITS =YES
MAX_OUTPUT = 1.0
# PID tuning params
DEADBAND = 0.15
P = 150.00
I = 0.0
D = 0.00
FF0 = 0.000
FF1 = 1.000
FF2 = 0.0
BIAS = 0.000
-ini file-
-hal file-
# standard components
loadrt pid num_chan=3
addf pid.0.do-pid-calcsservo-thread
addf pid.1.do-pid-calcsservo-thread
addf pid.2.do-pid-calcsservo-thread
setp hm2_7i43.0.pwmgen.pwm_frequency 193000
setp hm2_7i43.0.pwmgen.pdm_frequency 600
#
# Y [1] Axis
#
# axis enable chain
newsig emcmot.01.enable bit
sets emcmot.01.enable FALSE
net emcmot.01.enable = pid.1.enable
net emcmot.01.enable =
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, Oct 03, 2009 at 11:11:35AM -0400, Eric H. Johnson wrote: 1 When I try to run Setting | Calibration from tkemc, or the equivalent under axis I get an error of the form: ... If it matters, I am still running 2.3.0 as I am using the smp packages, and have not updated them to the subsequent minor releases. You can always see the bugs fixed in new releases on the wiki page http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Released This is the first link on the front page of the wiki. In this case you will see calibration now works with hostmot2-style hal files fixed in EMC 2.3.2. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, 3 Oct 2009, Eric H. Johnson wrote: Date: Sat, 3 Oct 2009 11:11:35 -0400 From: Eric H. Johnson ejohn...@camalytics.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: 'Enhanced Machine Controller (EMC)' emc-users@lists.sourceforge.net Subject: [Emc-users] PWM tuning with hostmot2 and 7i33 2 Tuning the servo motors I am using the 7i43 Anything I/O card with the 7i33 quad analog servo interface. I am having a devil of a time getting anything close to smooth motion from the motors in the PID tuning. I start, as I usually do by bringing up P, but I start to get oscillations with a P value of about 20. If I use this value to have it move to a position, it will over or undershoot the position by 1/2 (2500 encoder counts or 6/10ths of a turn of the motor shaft). The motor is not coupled to the load at this point. Increasing P to about 160 stiffens it up to the point where one would think it would get within an encoder count or two of the demanded position, however there is still a strong oscillation of about +/- 0.1 (500 encoder counts or roughly 1/10th turn of the motor shaft). I then try bringing up I and D, but it is generally making little difference until the values are large enough that it makes it worse. The basic problem is that it is so bad I am having trouble even establishing a starting point from which it will get better or worse. This is a retrofit of a system which previously used a Galil 1800 series motion controller, and where tuning with that system was no big deal. Galil does have a rather nice piece of tuning software, but I don't recall even needing that. My opinion is that you should _NEVER_ use _ANY_ I until you are within a gnats eyelash of perfect tuning. It really just gets in the way. I would make a test fixture so you can take a step motion, increase P until it overshoots in response to the step, add D until theres no or very little overshoot and repeat (increasing P and D) until you get good response to the step input. Then I would make another test with a long cruise, and adjust FF1 for minimum error. Only at this point would I start adding some I Additionally, about six months ago I replaced an EMC system using the VTI board (plus a 5i20 which only drove the laser) to use exclusively the 5i20 and 7i33 with the hostmot2 drivers. With the VTI card, tuning was a snap because it ran smoothly for a large range of PID values. When I switched it over to the 5i20, I again had a devil of a time getting it tuned, but finally got something reasonably acceptable, but never as good as when using the VTI board. It will still occasionally hum at idle for example, which never happened under the previous configuration. At the time, I thought it might be due to the PWM frequency, which I had to set to 25Khz, as that was the maximum frequency acceptable to the laser. With this configuration, there is no laser, so I have pwm_frequency set to 193Khz and pdm_frequency set to 6Mhz. PDM at 6 MHz is correct, but is it selected (PWM is default) I keep thinking it is some value other than the PID values which is throwing me, but so far I do not see it. I have included the relevant sections of the ini and hal files for the axis I am trying to tune below. -ini file- [AXIS_1] TYPE =LINEAR HOME =0.000 MAX_VELOCITY = 10.0 MAX_ACCELERATION = 40.0 BACKLASH = 0.000 INPUT_SCALE =- OUTPUT_SCALE =1.000 OUTPUT_OFFSET = 0.0 MIN_LIMIT = 0.0 MAX_LIMIT =180.0 FERROR =100.0 MIN_FERROR = 0.4 HOME_OFFSET =0.10 HOME_SEARCH_VEL = 0.10 HOME_LATCH_VEL = -0.01 HOME_USE_INDEX = NO HOME_IGNORE_LIMITS =YES MAX_OUTPUT = 1.0 # PID tuning params DEADBAND = 0.15 P = 150.00 I = 0.0 D = 0.00 FF0 = 0.000 FF1 = 1.000 FF2 = 0.0 BIAS = 0.000 -ini file- -hal file- # standard components loadrt pid num_chan=3 addf pid.0.do-pid-calcsservo-thread addf pid.1.do-pid-calcsservo-thread addf pid.2.do-pid-calcsservo-thread setp
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
Peter, Could you describe a bit more the test fixture you mention and the step motion. I'm not clear on this and would like to understand a bit better how to tune a servo as well. Thanks John On 3 Oct 2009 at 10:02, Peter C. Wallace wrote: My opinion is that you should _NEVER_ use _ANY_ I until you are within a gnats eyelash of perfect tuning. It really just gets in the way. I would make a test fixture so you can take a step motion, increase P until it overshoots in response to the step, add D until theres no or very little overshoot and repeat (increasing P and D) until you get good response to the step input. Then I would make another test with a long cruise, and adjust FF1 for minimum error. Only at this point would I start adding some I -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, 3 Oct 2009, John Thornton wrote: Date: Sat, 03 Oct 2009 12:28:19 -0600 From: John Thornton bjt...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller EEMC emc-users@lists.sourceforge.net Subject: Re: [Emc-users] PWM tuning with hostmot2 and 7i33 Peter, Could you describe a bit more the test fixture you mention and the step motion. I'm not clear on this and would like to understand a bit better how to tune a servo as well. Thanks John Either a gcode or HAL test setup that can take a step (instant jump in commanded position) so the step response of the servo can be captured via HALScope. I cant really imagine hand tuning without being able to see a plot of the servo systems step response. Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
Peter, My opinion is that you should _NEVER_ use _ANY_ I until you are within a gnats eyelash of perfect tuning. It really just gets in the way. I would make a test fixture so you can take a step motion, increase P until it overshoots in response to the step, add D until theres no or very little overshoot and repeat (increasing P and D) until you get good response to the step input. Then I would make another test with a long cruise, and adjust FF1 for minimum error. Only at this point would I start adding some I I agree with you, and that was where I started. I then read this: http://www.linuxcnc.org/docview/html//motion_pid_theory.html Near the bottom: If the system must remain online, one tuning method is to first set the I and D values to zero. Increase the P until the output of the loop oscillates. Then increase I until oscillation stops. Finally, increase D until the loop is acceptably quick to reach its reference. A fast PID loop tuning usually overshoots slightly to reach the setpoint more quickly; however, some systems cannot accept overshoot. Regardless, the oscillation is so bad that I cannot get a starting point for bringing in either D or I. Which is why I am suspecting I screwed up another parameter separate from PID. I just don't see it off hand. PDM at 6 MHz is correct, but is it selected (PWM is default) I am using both the 7i43 and 7i33, so the use of pwm or pdm is entirely internal to the Mesa products. The amplifier only cares about the resultant analog output. Which works best with the 7I33, pwm mode or pdm mode? What are the optimal settings? Thanks, Eric -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
Chris, Thanks, I should know by now to check that. If I get a chance, I will do another smp build this weekend to get everything caught up. Regards, Eric You can always see the bugs fixed in new releases on the wiki page http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Released This is the first link on the front page of the wiki. In this case you will see calibration now works with hostmot2-style hal files fixed in EMC 2.3.2. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
Ok, I think I understand now. So somethin to imput a change in the commanded position with a trigger for the scope and watch the commanded vs the actual position to tune that drive. How big of a step would you take? Thanks John On 3 Oct 2009 at 10:35, Peter C. Wallace wrote: Either a gcode or HAL test setup that can take a step (instant jump in commanded position) so the step response of the servo can be captured via HALScope. I cant really imagine hand tuning without being able to see a plot of the servo systems step response. Peter Wallace Mesa Electronics -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, 3 Oct 2009, Eric H. Johnson wrote: Date: Sat, 3 Oct 2009 15:18:26 -0400 From: Eric H. Johnson ejohn...@camalytics.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: 'Enhanced Machine Controller (EMC)' emc-users@lists.sourceforge.net Subject: Re: [Emc-users] PWM tuning with hostmot2 and 7i33 Peter, My opinion is that you should _NEVER_ use _ANY_ I until you are within a gnats eyelash of perfect tuning. It really just gets in the way. I would make a test fixture so you can take a step motion, increase P until it overshoots in response to the step, add D until theres no or very little overshoot and repeat (increasing P and D) until you get good response to the step input. Then I would make another test with a long cruise, and adjust FF1 for minimum error. Only at this point would I start adding some I I agree with you, and that was where I started. I then read this: http://www.linuxcnc.org/docview/html//motion_pid_theory.html Near the bottom: If the system must remain online, one tuning method is to first set the I and D values to zero. Increase the P until the output of the loop oscillates. Then increase I until oscillation stops. Finally, increase D until the loop is acceptably quick to reach its reference. A fast PID loop tuning usually overshoots slightly to reach the setpoint more quickly; however, some systems cannot accept overshoot. Regardless, the oscillation is so bad that I cannot get a starting point for bringing in either D or I. Which is why I am suspecting I screwed up another parameter separate from PID. I just don't see it off hand. PDM at 6 MHz is correct, but is it selected (PWM is default) I am using both the 7i43 and 7i33, so the use of pwm or pdm is entirely internal to the Mesa products. The amplifier only cares about the resultant analog output. Which works best with the 7I33, pwm mode or pdm mode? What are the optimal settings? PDM 6MHz, PWM/PDM selection is a HostMot2 setup option Thanks, Eric -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, 3 Oct 2009, Eric H. Johnson wrote: Date: Sat, 3 Oct 2009 15:18:26 -0400 From: Eric H. Johnson ejohn...@camalytics.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: 'Enhanced Machine Controller (EMC)' emc-users@lists.sourceforge.net Subject: Re: [Emc-users] PWM tuning with hostmot2 and 7i33 Peter, My opinion is that you should _NEVER_ use _ANY_ I until you are within a gnats eyelash of perfect tuning. It really just gets in the way. I would make a test fixture so you can take a step motion, increase P until it overshoots in response to the step, add D until theres no or very little overshoot and repeat (increasing P and D) until you get good response to the step input. Then I would make another test with a long cruise, and adjust FF1 for minimum error. Only at this point would I start adding some I I agree with you, and that was where I started. I then read this: http://www.linuxcnc.org/docview/html//motion_pid_theory.html Near the bottom: If the system must remain online, one tuning method is to first set the I and D values to zero. Increase the P until the output of the loop oscillates. Then increase I until oscillation stops. Finally, increase D until the loop is acceptably quick to reach its reference. A fast PID loop tuning usually overshoots slightly to reach the setpoint more quickly; however, some systems cannot accept overshoot. Regardless, the oscillation is so bad that I cannot get a starting point for bringing in either D or I. Which is why I am suspecting I screwed up another parameter separate from PID. I just don't see it off hand. Heres what I would check: Can you get a HALScope plot of the step response? Do you have velocity or torque mode amplifiers? (Torque mode amplifiers will typically require a higher sample rate and are tougher to tune) your .6 error even with a P of 20 suggests torque mode to me What number of counts generates a full scale drive (+- 10V) with your current P setting? (Disconnect analog out from amps and measure voltage versus error counts) PDM at 6 MHz is correct, but is it selected (PWM is default) I am using both the 7i43 and 7i33, so the use of pwm or pdm is entirely internal to the Mesa products. The amplifier only cares about the resultant analog output. Which works best with the 7I33, pwm mode or pdm mode? What are the optimal settings? Thanks, Eric -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
On Fri, 02 Oct 2009 15:24:24 -0400, you wrote: Page 5 and 6 show it but not at a good time scale, page 7 from the base thread sample shows it very clearly Steve. Noise. Until that is gone (and encoder A output could have a closer to 50% duty cycle too, I'd almost return that one in fact if its sealed and non adjustable), it isn't going to work, not even if we make sacrifices. :) I have to assume the encoders cabling is shielded, and the shield ends at the encoder so there is no connection via the shield to the machine by way of how the encoder is mounted and driven. That would be what we call a ground loop, and that is usually a no-no. Thanks Gene, that gave me clue and I found it - The encoder cable had a strand from the shield touching the plug at the controller end. Much, much better now, but still has the odd glitch, from where I don't know. disconnecting all the grounds didn't get rid of it. As for the 50% duty cycle, can't do anything about that other than replace the encoder. But - running at slow speed it's MUCH better, and running my test 1.5mm pitch test file at my normal 700 rpm it's not noticeable at all. Have a look at the difference :) http://filebin.ca/brcenc/encoder.pdf Steve Blackmore -- -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
Peter, Heres what I would check: Can you get a HALScope plot of the step response? Yes, but not until Monday when I will be back at the shop. Do you have velocity or torque mode amplifiers? (Torque mode amplifiers will typically require a higher sample rate and are tougher to tune) your .6 error even with a P of 20 suggests torque mode to me. Velocity If it is of any value, although I know they are not directly comparable, the PID values when using the Galil controller were: P: 94.25 I: 0.6 D: 1005.63 What number of counts generates a full scale drive (+- 10V) with your current P setting? (Disconnect analog out from amps and measure voltage versus error counts) Again I can get that for you on Monday. Thanks again, Eric -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, 3 Oct 2009, Eric H. Johnson wrote: Date: Sat, 3 Oct 2009 16:14:20 -0400 From: Eric H. Johnson ejohn...@camalytics.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: 'Enhanced Machine Controller (EMC)' emc-users@lists.sourceforge.net Subject: Re: [Emc-users] PWM tuning with hostmot2 and 7i33 Peter, Heres what I would check: Can you get a HALScope plot of the step response? Yes, but not until Monday when I will be back at the shop. Do you have velocity or torque mode amplifiers? (Torque mode amplifiers will typically require a higher sample rate and are tougher to tune) your .6 error even with a P of 20 suggests torque mode to me. Velocity So how can a .6 error which must be a large number of encoder counts not generate even a small velocity to correct the error, something is really wrong here... Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
On Sat, 3 Oct 2009, John Thornton wrote: Date: Sat, 03 Oct 2009 14:26:19 -0600 From: John Thornton bjt...@gmail.com Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller EEMC emc-users@lists.sourceforge.net Subject: Re: [Emc-users] PWM tuning with hostmot2 and 7i33 Ok, I think I understand now. So somethin to imput a change in the commanded position with a trigger for the scope and watch the commanded vs the actual position to tune that drive. How big of a step would you take? Thanks John Big enough so the encoder resolution and any mechanical backlash are swamped out by the size of the move say a 1/4 inch or so. Depending on the exact drive/mechanical characteristics, you may need to limit the acceleration to prevent damage On 3 Oct 2009 at 10:35, Peter C. Wallace wrote: Either a gcode or HAL test setup that can take a step (instant jump in commanded position) so the step response of the servo can be captured via HALScope. I cant really imagine hand tuning without being able to see a plot of the servo systems step response. Peter Wallace Mesa Electronics -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] PWM tuning with hostmot2 and 7i33
Peter, Exactly, which is why by the end of the day yesterday I was strongly suspecting that I had screwed up someplace separate from PID tuning, like MAX_VELOCITY, MAX_ACCELERATION the relationship to input and output scales. Although I already rechecked those and they seem to be correct. I will dig back into it on Monday. Regards, Eric So how can a .6 error which must be a large number of encoder counts not generate even a small velocity to correct the error, something is really wrong here... -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing
On Sat, Oct 03, 2009 at 09:21:43PM +0100, Steve Blackmore wrote: Ahh - it's a second one being added not a replacement for the existing, even though it's an obsolete Fanuc foible? I thought that was clear from the start. If you're up to adding second commands, there should be no objection then to adding a current Fanuc lathe command like G32 with F for the feed word that also does taper threads properly (along the Z axis NOT the hypotenuse) in addition to the G33 ;) No I wouldn't object to someone adding G32. Do you plan to contribute this? I'd happily review this contribution. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Line Filters
Are RFI filters for inverters generally incompatible with RCDs? I fitted one to my machine today to try to get rid of the noise from the VFD which seems to interfere with my encoders and limit switches, however every time I power up the VFD the lights go out and the power goes off. The garage and shed are fed though a 30mA RCD (a requirement for power to a shed AFAIK) and that seems to take offence to the Filter. The filter is marked nominal leakage curent 20mA which might be a clue. -- atp -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing
On Sat, 3 Oct 2009 16:59:36 -0500, you wrote: On Sat, Oct 03, 2009 at 09:21:43PM +0100, Steve Blackmore wrote: Ahh - it's a second one being added not a replacement for the existing, even though it's an obsolete Fanuc foible? I thought that was clear from the start. No - it wasn't. If you're up to adding second commands, there should be no objection then to adding a current Fanuc lathe command like G32 with F for the feed word that also does taper threads properly (along the Z axis NOT the hypotenuse) in addition to the G33 ;) No I wouldn't object to someone adding G32. Do you plan to contribute this? I'd happily review this contribution. Yes - how do I go about it. Steve Blackmore -- -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Line Filters
On Sat, 3 Oct 2009 23:29:15 +0100, you wrote: Are RFI filters for inverters generally incompatible with RCDs? I fitted one to my machine today to try to get rid of the noise from the VFD which seems to interfere with my encoders and limit switches, however every time I power up the VFD the lights go out and the power goes off. The garage and shed are fed though a 30mA RCD (a requirement for power to a shed AFAIK) and that seems to take offence to the Filter. The filter is marked nominal leakage curent 20mA which might be a clue. I just use a 40A Type 3 MCB, on the circuit for the machines, works fine. I have a 20A RCD which just goes to one double socket near the shop door, that's used for outdoor or portable equipment. Steve Blackmore -- -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
[Emc-users] Shutdown event
I'm writing a python user component to display data on an LCD. It all works fine except when Axis/Hal shuts down, the LCD is left displaying whatever was there last. Is there a signal/event/pin that I can action off to clear the display before shutting down? The python user component talks to a C++ user component which controls the LCD. This seems to disappear first in shutdown order, so I need an earlier notification. Changing the C++ component to always clear on shutdown is an option, but I'd rather not force it do the clear. I'm using the python hal and emc components. Thanks, Frank -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
On Saturday 03 October 2009, Steve Blackmore wrote: On Fri, 02 Oct 2009 15:24:24 -0400, you wrote: Page 5 and 6 show it but not at a good time scale, page 7 from the base thread sample shows it very clearly Steve. Noise. Until that is gone (and encoder A output could have a closer to 50% duty cycle too, I'd almost return that one in fact if its sealed and non adjustable), it isn't going to work, not even if we make sacrifices. :) I have to assume the encoders cabling is shielded, and the shield ends at the encoder so there is no connection via the shield to the machine by way of how the encoder is mounted and driven. That would be what we call a ground loop, and that is usually a no-no. Thanks Gene, that gave me clue and I found it - The encoder cable had a strand from the shield touching the plug at the controller end. Much, much better now, but still has the odd glitch, from where I don't know. disconnecting all the grounds didn't get rid of it. As for the 50% duty cycle, can't do anything about that other than replace the encoder. But - running at slow speed it's MUCH better, and running my test 1.5mm pitch test file at my normal 700 rpm it's not noticeable at all. Have a look at the difference :) http://filebin.ca/brcenc/encoder.pdf That looks better, but something is still giving the encoder.0.velocity a big kick occasionally. One page one it almost corresponds to the single pulse in the bottom, white trace that I don't see a caption for, and looks like its quite close to the edge of the non-50% A trace. Except for that big spike, which corresponds to a single pulse, not a dual pulse, in the bottom trace for each half cycle of the encoder b signal. The expanded version on page 6 looks as if its working there. Steve Blackmore -- --- --- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. https://www.nrahq.org/nrabonus/accept-membership.asp Simon: It was either that or the National Anthem. Reports vary. --Episode #14, Objects in Space -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Line Filters
On Saturday 03 October 2009, Andy Pugh wrote: Are RFI filters for inverters generally incompatible with RCDs? I fitted one to my machine today to try to get rid of the noise from the VFD which seems to interfere with my encoders and limit switches, however every time I power up the VFD the lights go out and the power goes off. Andy, Is your 'RCD' the same as what we call GFCI, ground fault current interrupter over on this side of the pond? The garage and shed are fed though a 30mA RCD (a requirement for power to a shed AFAIK) and that seems to take offence to the Filter. The filter is marked nominal leakage curent 20mA which might be a clue. 20 to 30 ma can be fatal under the right conditions, our GFCI's normally trip at about 20 microamps IIRC. -- Cheers, Gene There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. https://www.nrahq.org/nrabonus/accept-membership.asp My sense of purpose is gone! I have no idea who I AM! Oh, my God... You've.. You've turned him into a DEMOCRAT! -- Doonesbury -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
when you get a chance - try the interpolated output from the encoder. sam Steve Blackmore wrote: On Fri, 02 Oct 2009 15:24:24 -0400, you wrote: Page 5 and 6 show it but not at a good time scale, page 7 from the base thread sample shows it very clearly Steve. Noise. Until that is gone (and encoder A output could have a closer to 50% duty cycle too, I'd almost return that one in fact if its sealed and non adjustable), it isn't going to work, not even if we make sacrifices. :) I have to assume the encoders cabling is shielded, and the shield ends at the encoder so there is no connection via the shield to the machine by way of how the encoder is mounted and driven. That would be what we call a ground loop, and that is usually a no-no. Thanks Gene, that gave me clue and I found it - The encoder cable had a strand from the shield touching the plug at the controller end. Much, much better now, but still has the odd glitch, from where I don't know. disconnecting all the grounds didn't get rid of it. As for the 50% duty cycle, can't do anything about that other than replace the encoder. But - running at slow speed it's MUCH better, and running my test 1.5mm pitch test file at my normal 700 rpm it's not noticeable at all. Have a look at the difference :) http://filebin.ca/brcenc/encoder.pdf Steve Blackmore -- -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
2009/10/4 sam sokolik sa...@empirescreen.com: when you get a chance - try the interpolated output from the encoder. He already has, though perhaps not since fixing the noise. -- atp -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Line Filters
Andy Pugh wrote: Are RFI filters for inverters generally incompatible with RCDs? Yes, they can be. Boxed RFI filters have capacitors to ground, so necessarily they divert some mains current to safety ground. If that current is above the threshold of the RDC, it has to trip. You might be able to find a medical-grade filter or some other with extra-low ground current. Jon -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
Andy Pugh wrote: 2009/10/4 Gene Heskett gene.hesk...@gmail.com: That looks better, but something is still giving the encoder.0.velocity a big kick occasionally. I think those are on the occasions that both channels change state in the same sample. That does mean infinite velocity, after all. (Does the encoder code cap velocity at 1/base thread frequency?) I suspect that is due to aliasing and the short duty-cycle of the A channel. Occasionally you get unlucky with the sample frequency and catch both changing at the same time. That represents an illegal transition, and should be rejected. At the worst case, it could trick the logic into altering the position by 4 counts. If there is a burst of noise on both A and B at the same time, it could maybe cause more counts than that to accumulate. Have you tried putting pull-up resistors on the A and B lines? I think you have made progress, but it looks like this is not yet working well enough for machining. Jon -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Line Filters
On Saturday 03 October 2009, Andy Pugh wrote: 2009/10/4 Gene Heskett gene.hesk...@gmail.com: Andy, Is your 'RCD' the same as what we call GFCI, ground fault current interrupter over on this side of the pond? Probably. It checks current balance between neutral and live. 20 to 30 ma can be fatal under the right conditions, our GFCI's normally trip at about 20 microamps IIRC. These are intended to spot cable damage or live to earh faults, rather than save you from grabbing live, as I understand it. Well, in any event, a large amount of capacitance (without some you don't have a filter) has been known to trip our GFCI devices. Possibly your RCD is sensitive to that too. But not being familiar with your version of the NEC, anything I'd say is a SWAG (Scientific Wild Assed Guess) anyway. :) -- Cheers, Gene There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. https://www.nrahq.org/nrabonus/accept-membership.asp A fool and his money are soon using Windows. -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Encoders
On Saturday 03 October 2009, Steve Blackmore wrote: On Fri, 02 Oct 2009 15:24:24 -0400, you wrote: Page 5 and 6 show it but not at a good time scale, page 7 from the base thread sample shows it very clearly Steve. Noise. Until that is gone (and encoder A output could have a closer to 50% duty cycle too, I'd almost return that one in fact if its sealed and non adjustable), it isn't going to work, not even if we make sacrifices. :) I have to assume the encoders cabling is shielded, and the shield ends at the encoder so there is no connection via the shield to the machine by way of how the encoder is mounted and driven. That would be what we call a ground loop, and that is usually a no-no. Thanks Gene, that gave me clue and I found it - The encoder cable had a strand from the shield touching the plug at the controller end. Ideally it should be connected solidly at the controller, and not connected at the encoder end unless the encoder mount is isolated from the machine. Shielding carried into the encoder housing is a good idea, as long as it doesn't have a connection to the shaft or the mounting. All shielding should be connected to the controller. I ran a piece of 12 gauge copper wire around the outside of the box I made for my xylotex controller, it is tied to the - rail of the motor psu, all motor cable shields are tied to it, and of course the ground wire from the computers parport is also tied there, all solidly soldered with a silver bearing solder, 3% silver I think, the rest the usual eutectic blend. Motor cables, and interconnect cables for the spindle VSR control (a PMDX-106, works great) are all in a microphone cable that Belden calls 'star- quad', which has 4 wires and a mylar foil shield covered with about a 96% tinned copper braid. Very good cable IMO. This sets up what we call a star ground system, where every signal ground in the system comes to one common point. Any currents that flow, because there is only one common point, cannot develop a stray signal due to the resistance or inductance of the ground because everything is referenced to that one common point, in this case about 8 of 12 gauge bare wire so there is room to solder all the shields to it. I think it works well, I have used an optical probe to scan surfaces as described by one of the guys here, several times and the biggest error is the sideways slop in my probe, it may flex or take up the slack in the slip tubing as it slides downhill on a curved surface. Much, much better now, but still has the odd glitch, from where I don't know. disconnecting all the grounds didn't get rid of it. As for the 50% duty cycle, can't do anything about that other than replace the encoder. But - running at slow speed it's MUCH better, and running my test 1.5mm pitch test file at my normal 700 rpm it's not noticeable at all. Have a look at the difference :) http://filebin.ca/brcenc/encoder.pdf Steve Blackmore -- --- --- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order. -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. https://www.nrahq.org/nrabonus/accept-membership.asp Goals... Plans... they're fantasies, they're part of a dream world... -- Wally Shawn -- Come build with us! The BlackBerryreg; Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9#45;12, 2009. Register now#33; http://p.sf.net/sfu/devconf ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
