Re: [Emc-users] Optoisolater timings (was: Z axis stepper gradually losing position)

[Stephen Dubovsky]

FWIW, the iCoupler type things from ADI and Silicon Devices are faster,
cheaper, better isolation, and lower powered than high speed optos.  win,
win, win, win;)

On Mon, Dec 14, 2015 at 7:11 PM, Jerry Scharf  wrote:

> Hi,
>
> Just did a super quick google search and came up with a fairchild
> optocoupler hcpl2530 that will do 1Mbps. ~1.80 USD quantity 1. Isolation to
> 480v and good common mode rejection. There are a number of devices in
> similar and better speeds.
>
> That's not anywhere near the top speed for laser/detector systems, which
> now run to 100Gbps and beyond.
>
> opto stuff is so much cheaper than it used to be. The combination of insane
> laser volume and the demand for ultra speed detectors have made fast stuff
> really cheap.
>
> jerry
>
>
> On Mon, Dec 14, 2015 at 1:57 PM, Gene Heskett  wrote:
>
> > On Monday 14 December 2015 16:01:26 Ben Potter wrote:
> >
> > > > Note that those setup and hold times are relative to the riseing
> > > > edge of
> > >
> > > the (step?) pulse, and the next line is not so specific, but I expect
> > > it needs to be checked by a dual trace scope for both
> > >
> > > > conditions
> > >
> > > I'm very tempted to pull the G540 from the router and rig up a test
> > > bench test to see if I can get my head around why this is happening.
> > > Might get time over christmas.
> > >
> > > Would be nice to know why inverting the step output works for me,
> > > rather than 'it just does' I'm starting to suspect that the 5i25 obeys
> > > the set timings, whereas mach on a parallel port uses them as a
> > > minimum guide, and frequently exceeds them.
> > >
> > > > > I have no additional opto-isolation in that path - I believe that
> > > > > the G540 uses fast opto's on all the parallel port pins (from the
> > > > > manual, I'm sure there was a post on cnczone detailed the choice
> > > > > of isolater somewhere)
> > > >
> > > > Thanks for that , so it would have been DIRSETUP/DIRHOLD that I was
> > >
> > > concerned with.
> > >
> > > I managed to dig out the thread where Mariss of Gecko was talking
> > > about opto circuits.
> > > http://www.cnczone.com/forums/general-cnc-machine-related-electronics/
> > >23216- optoisolator-circuit.html
> > >
> > > Posts #2 and #6 are particularly interesting (not sure on cross-post
> > > etiquette here), and possibly give a hint as to the root cause of my
> > > problem.
> > >
> > > > > 
> > > >
> > > > And that gives you far finer tools to tune with than software
> > > > stepping
> > >
> > > ever will.  There may better interfaces than the 5i25, but for us
> > > stepper people, its the cats meow.  Not bulletproof on its inputs, I
> > > didn't have a good enough > grounding setup wrapped around my G0704,
> > > and apparently blew the input I was using for a probe.
> > >
> > > > I don't know as Peter could tell me which chip to replace to rescue
> > > > it. I
> > >
> > > AM a C.E.T. and in my dayjob before I retired in 2002/6/30, I could
> > > have done it easily, but at 81, my hands aren't as steady as they once
> > > were.
> > >
> > > They do pretty nicely on servo stuff too - I have a 5i25 on the
> > > (servo) bridgeport, the (stepepr) lathe was converted earlier, and
> > > that has a 5i20 on.
> > >
> > > > I can't comment based on experience with them so I won't, Ben.
> > > > Other than
> > >
> > > to say that 98% of the opto stuff out there, will need a pulse in
> > > excess of 1 microsecond on, and often pushing 2 u-s to turn off. I
> > > understand there are
> > >
> > > > some Gas based optos about, but they'd have a serious effect on a
> > > > BoB's
> > >
> > > price.  One could turn a $15 BoB into a $100 BoB pretty fast.
> > >
> > > From the thread above it looks like Gecko use the HCPL-2531 in at
> > > least some of their drives - price of $0.87 per 1k doesn't look too
> > > bad for a fast dual channel opto.
> > >
> > > > However, one must bear in mind that when looking at it with a scope,
> > > > we
> > >
> > > are watching the voltage, and in opto stuff, voltage doesn't mean near
> > > as much as actually measuring the current.  Why?  Because when the
> > >
> > > > driving led in the opto goes out, which it might do at 1.85 volts or
> > > > as high as 2.4 volts, the load is gone, leaving the voltage to decay
> > >
> > > toward (which ever rail its headed for) at a very leasurely rate.
> > >
> > > > Thats a fancy, CMA way to say the scope is lieing to you.  So I tend
> > > > to
> > >
> > > look at the decay with an eye toward seeing if I can define that point
> > > where the down (up?)ward curve changes to a slower rate, then make the
> > > "on time" timing > measurements to that point. That can be a difficult
> > > point to define even for me, and I've "had a scope probe in one hand"
> > >
> > > > for 64 years. 64 years ago it was a 5mhz Hickock, today I have
> > > > 100MHZ dual
> > >
> > > trace analog, and 200mhz dual trace digitals to go poking around with.
> > >
> > > > Cheers, Gene 

Re: [Emc-users] Z axis stepper gradually losing position

[Jerry Scharf]

Gene,

I hear what you are saying about old hands and working on boards. I am only
pushing 60, but the company I work for regularly uses 0201 smt devices. Too
damn small for these hands, even with the slickest working microscope out
there. Just pumping the solder on and putting the thing in place it too
hard for me. The folks use @$100 each tweezers because anything less can't
work with the small parts reliably. Then the IC guys laugh at the large
dimension when they have to debug chips that have been opened up with a FIB.

jerry

On Mon, Dec 14, 2015 at 11:41 AM, Gene Heskett  wrote:

> On Sunday 13 December 2015 14:39:19 Ben Potter wrote:
>
> > > > When going through my testing for this the first time I cranked
> > > > all 4 settings up to 10,000 - the problem still occurred. After I
> > > > tried inverting the output I slowly stepped them back down - for
> > > > my G540 I settled on 700/700/2000/2000.
> > >
> > > The Gecko 540 is not in the charts of our wiki, darnit. What is
> > > there
> >
> > isn't even that fast. See:
> >
> > Yeah, I've thought about adding it a couple of times - but would want
> > to do some more... intense testing before adding my timings there.
> >
> Note that those setup and hold times are relative to the riseing edge of
> the (step?) pulse, and the next line is not so specific, but I expect it
> needs to be checked by a dual trace scope for both
> conditions
>   .
> > > 
> > >
> > > I take it you do not have any opto-isolation in those 3 paths.  That
> > > 700
> >
> > ns is pushing an opto's ability to switch that fast.  The BoB I used
> > was all opto, and I was warned about its speed by someone (Steve
> > Stallings?) on this list.
>
> > I don't recall which channel now, but I had to remove one of
> > > them
> >
> > and jumper across it. I think there are probably faster opto's about,
> > but what I saw on the scope just wasn't up to getting the job done.
> > All the loads that
> >
> > > BoB see's are already isolated, so I wasn't terribly concerned about
> >
> > losing one stage of isolation.
> >
> > I have no additional opto-isolation in that path - I believe that the
> > G540 uses fast opto's on all the parallel port pins (from the manual,
> > I'm sure there was a post on cnczone detailed the choice of isolater
> > somewhere)
> >
> > To clarify, the figures I gave were in the format
> > DIRSETUP/DIRHOLD/STEPLEN/STEPSPACE.
> >
> Thanks for that , so it would have been DIRSETUP/DIRHOLD that I was
> concerned with.
>
> > Gecko give their recommendations on timings for the drive here:
> > http://www.geckodrive.com/geckodrive-step-motor-drives/g540.html
> >
> > Those indicate 2000 nS for '0' on-time, 1000 nS for '1' on-time, 200
> > nS for direction setup and hold. So it looks like I'm just within
> > their recommendations on step length.
>
> And that gives you far finer tools to tune with than software stepping
> ever will.  There may better interfaces than the 5i25, but for us
> stepper people, its the cats meow.  Not bulletproof on its inputs, I
> didn't have a good enough grounding setup wrapped around my G0704, and
> apparently blew the input I was using for a probe.
>
> I don't know as Peter could tell me which chip to replace to rescue it. I
> AM a C.E.T. and in my dayjob before I retired in 2002/6/30, I could have
> done it easily, but at 81, my hands aren't as steady as they once were.
>
> > I'm hooked up to a 5i25 instead of a parport though.
> >
> > > All my drivers are just 3 types, 2M542's, 2m860 and Pico pwm-servo's
> > > for 2 of the 3 spindles at my place.  And I'm not pushing any of
> > > them that
> >
> > fast.  But because of that slow BoB, ISTR I am running dir setup and
> > dir hold about 1.5x longer than the wiki shows for the LeadShines.  So
> > my experience is not > with a wide range of drivers, but I will no
> > longer consider opto-isolated BoB's because everything I have is
> > already isolated. Best BoB IMO, 10ns response times, but its been
> > taken down, is the cnc4pc C1G that I have 2 of.  What he > is selling
> > now is NOT the versions I have. Everything on mine has an led tally,
> > which simplifies troubleshooting considerably.
> >
> > > Also, generally, where you have the choice of commonizing the +
> > > terminal
> >
> > of a driver loads input, you are far better off doing that, and having
> > the BoB pull it to ground as the pulldown in most TTL circuits is much
> > more robust. > Having the reverse setup, where the - terminals are
> > commonized, is generally NOT a good idea due to a lesser amount of
> > pullup power to light up the opto in the drivers own input.
> >
> > I've gone to using mesa cards for pretty much all my interface as far
> > as possible, I've had odd issues with Gecko and Leadshine drives, I've
> > managed to work around them so far. The industrial drives I have used
> > have generally behaved better. Since the machines I'm converting 

Re: [Emc-users] Soft starting my mills spindle supply

[andy pugh]

> As I reported, I have 4 of them coming.

The forcibly guided relay for mine arrived today, so I finished
assembling the PSU and then drew a schematic of what I ended up with.

I am using the physical relay to ensure that I can't possibly power
the system up with the discharge resistor in circuit. So, if the
discharge contacts on the relay weld closed, the input SSR can't be
energised.
I ended up with a 6-pole relay. A 2-pole NO/NC relay would have worked, though.

620R is actually a bit high for the soft-start resistor. It seems
about right for the discharge resistor.

-- 
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto


PSU - Schematic.pdf
Description: Adobe PDF document
--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[John Thornton]

No, I've seen that and could not get it to work. Too complicated for the 
job anyway.


On 12/14/2015 11:49 AM, Viesturs Lācis wrote:
> 2015-12-14 14:32 GMT+02:00 John Thornton :
>> Crumb, I hit delete on your reply and it does not show up in the trash
>> folder... which probe screen are you talking about?
>
> Andy posted this link (if you were asking for it):
> https://forum.linuxcnc.org/forum/49-basic-configuration/29187-work-with-probe?limitstart=0
>
> Viesturs
>
> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Optoisolater timings (was: Z axis stepper gradually losing position)

[Jerry Scharf]

Hi,

Just did a super quick google search and came up with a fairchild
optocoupler hcpl2530 that will do 1Mbps. ~1.80 USD quantity 1. Isolation to
480v and good common mode rejection. There are a number of devices in
similar and better speeds.

That's not anywhere near the top speed for laser/detector systems, which
now run to 100Gbps and beyond.

opto stuff is so much cheaper than it used to be. The combination of insane
laser volume and the demand for ultra speed detectors have made fast stuff
really cheap.

jerry


On Mon, Dec 14, 2015 at 1:57 PM, Gene Heskett  wrote:

> On Monday 14 December 2015 16:01:26 Ben Potter wrote:
>
> > > Note that those setup and hold times are relative to the riseing
> > > edge of
> >
> > the (step?) pulse, and the next line is not so specific, but I expect
> > it needs to be checked by a dual trace scope for both
> >
> > > conditions
> >
> > I'm very tempted to pull the G540 from the router and rig up a test
> > bench test to see if I can get my head around why this is happening.
> > Might get time over christmas.
> >
> > Would be nice to know why inverting the step output works for me,
> > rather than 'it just does' I'm starting to suspect that the 5i25 obeys
> > the set timings, whereas mach on a parallel port uses them as a
> > minimum guide, and frequently exceeds them.
> >
> > > > I have no additional opto-isolation in that path - I believe that
> > > > the G540 uses fast opto's on all the parallel port pins (from the
> > > > manual, I'm sure there was a post on cnczone detailed the choice
> > > > of isolater somewhere)
> > >
> > > Thanks for that , so it would have been DIRSETUP/DIRHOLD that I was
> >
> > concerned with.
> >
> > I managed to dig out the thread where Mariss of Gecko was talking
> > about opto circuits.
> > http://www.cnczone.com/forums/general-cnc-machine-related-electronics/
> >23216- optoisolator-circuit.html
> >
> > Posts #2 and #6 are particularly interesting (not sure on cross-post
> > etiquette here), and possibly give a hint as to the root cause of my
> > problem.
> >
> > > > 
> > >
> > > And that gives you far finer tools to tune with than software
> > > stepping
> >
> > ever will.  There may better interfaces than the 5i25, but for us
> > stepper people, its the cats meow.  Not bulletproof on its inputs, I
> > didn't have a good enough > grounding setup wrapped around my G0704,
> > and apparently blew the input I was using for a probe.
> >
> > > I don't know as Peter could tell me which chip to replace to rescue
> > > it. I
> >
> > AM a C.E.T. and in my dayjob before I retired in 2002/6/30, I could
> > have done it easily, but at 81, my hands aren't as steady as they once
> > were.
> >
> > They do pretty nicely on servo stuff too - I have a 5i25 on the
> > (servo) bridgeport, the (stepepr) lathe was converted earlier, and
> > that has a 5i20 on.
> >
> > > I can't comment based on experience with them so I won't, Ben.
> > > Other than
> >
> > to say that 98% of the opto stuff out there, will need a pulse in
> > excess of 1 microsecond on, and often pushing 2 u-s to turn off. I
> > understand there are
> >
> > > some Gas based optos about, but they'd have a serious effect on a
> > > BoB's
> >
> > price.  One could turn a $15 BoB into a $100 BoB pretty fast.
> >
> > From the thread above it looks like Gecko use the HCPL-2531 in at
> > least some of their drives - price of $0.87 per 1k doesn't look too
> > bad for a fast dual channel opto.
> >
> > > However, one must bear in mind that when looking at it with a scope,
> > > we
> >
> > are watching the voltage, and in opto stuff, voltage doesn't mean near
> > as much as actually measuring the current.  Why?  Because when the
> >
> > > driving led in the opto goes out, which it might do at 1.85 volts or
> > > as high as 2.4 volts, the load is gone, leaving the voltage to decay
> >
> > toward (which ever rail its headed for) at a very leasurely rate.
> >
> > > Thats a fancy, CMA way to say the scope is lieing to you.  So I tend
> > > to
> >
> > look at the decay with an eye toward seeing if I can define that point
> > where the down (up?)ward curve changes to a slower rate, then make the
> > "on time" timing > measurements to that point. That can be a difficult
> > point to define even for me, and I've "had a scope probe in one hand"
> >
> > > for 64 years. 64 years ago it was a 5mhz Hickock, today I have
> > > 100MHZ dual
> >
> > trace analog, and 200mhz dual trace digitals to go poking around with.
> >
> > > Cheers, Gene Heskett
> >
> > Good to know, I have a rescued tektronix scope which I rarely get to
> > use. Hints on those things that are only learned through experience
> > are always appreciated.
> >
> > I suspect spotting most of the ways phase shift can trip you up even
> > on simple circuits takes quite a bit of practice.
> >
> That, and ingenuity in figuring out how best to get at it with a probe.
> And sometimes you can't, you have to go well beyond and let experience

Re: [Emc-users] Practical Probing Routines

[andy pugh]

On 14 December 2015 at 12:02, John Thornton  wrote:
> With a probe on the way and after viewing a few probe screens which seem
> to all be way to complicated for the job it made me wonder what
> practical probing routines people would actually use on a mill to
> machine parts with.

I have the probe-hole.ngc file from the sample folder set up as a
macro in Touchy, and type G38,2 the rest of the time.

However, I fully intend to install the probe-tab from Verser
https://forum.linuxcnc.org/forum/49-basic-configuration/29187-work-with-probe?limitstart=0

Which may well do too much, but why would that be a problem?

I have actually installed it in my hobbing config, and it was very
little trouble. Though there is no scope for probing at all with my
hobbing setup, it was just a trial.

-- 
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[Sarah Armstrong]

it looks as if it's the same package you have looked at . done by the guys
over on the russian site
theirs some probe stuff in the ngc folder .

i have some too that might help , i'll dig them and emails shortly all
being well

On 14 December 2015 at 12:32, John Thornton  wrote:

> Crumb, I hit delete on your reply and it does not show up in the trash
> folder... which probe screen are you talking about?
>
> JT
>
> On 12/14/2015 6:02 AM, John Thornton wrote:
> > With a probe on the way and after viewing a few probe screens which seem
> > to all be way to complicated for the job it made me wonder what
> > practical probing routines people would actually use on a mill to
> > machine parts with. I came up with a few but having never probed a part
> > I'm looking for input from those that have probes now.
> >
> > Measuring a part.
> >   Measure a hole.
> >   Measure a pocket.
> >
> > Re-Machining
> >   Locate a hole.
> >
> > Setup
> >   Find the top of material.
> >   Check that the vise is square.
> >   Center the probe stylus.
> >
> > JT
> >
> >
> --
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
>
> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>



-- 

The information contained in this message is confidential and is intended
for the addressee only. If you have received this message in error or there
are any problems please notify the originator immediately. The unauthorised
use, disclosure, copying or alteration of this message is strictly
forbidden. This mail and any attachments have been scanned for viruses
prior to leaving the RcTechnix network. RcTechnix will not be liable for
direct, special, indirect or consequential damages arising from alteration
of the contents of this message by a third party or as a result of any
virus being passed on.

RcTechnix reserves the right to monitor and record e-mail messages being
sent to and from this address for the purposes of investigating or
detecting any unauthorised use of its system and ensuring effective
operation.

(c) RcTechnix
--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[John Thornton]

Yes, I attempted to get it to work but failed to do so and yes way to 
complicated with all the .axisrc additions. I also was annoyed by the 
size of it, every time I go to that tab half is not there so you have to 
make the screen bigger... it was late last night when I tried. All the 
cool graphics on the buttons is very pretty but the settings are hard to 
interpret unless you hover the mouse over each one. And then there is 
the metric thing lol...

JT

On 12/14/2015 6:14 AM, andy pugh wrote:
> On 14 December 2015 at 12:02, John Thornton  wrote:
>> With a probe on the way and after viewing a few probe screens which seem
>> to all be way to complicated for the job it made me wonder what
>> practical probing routines people would actually use on a mill to
>> machine parts with.
> I have the probe-hole.ngc file from the sample folder set up as a
> macro in Touchy, and type G38,2 the rest of the time.
>
> However, I fully intend to install the probe-tab from Verser
> https://forum.linuxcnc.org/forum/49-basic-configuration/29187-work-with-probe?limitstart=0
>
> Which may well do too much, but why would that be a problem?
>
> I have actually installed it in my hobbing config, and it was very
> little trouble. Though there is no scope for probing at all with my
> hobbing setup, it was just a trial.
>


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[John Thornton]

Crumb, I hit delete on your reply and it does not show up in the trash 
folder... which probe screen are you talking about?

JT

On 12/14/2015 6:02 AM, John Thornton wrote:
> With a probe on the way and after viewing a few probe screens which seem
> to all be way to complicated for the job it made me wonder what
> practical probing routines people would actually use on a mill to
> machine parts with. I came up with a few but having never probed a part
> I'm looking for input from those that have probes now.
>
> Measuring a part.
>   Measure a hole.
>   Measure a pocket.
>
> Re-Machining
>   Locate a hole.
>
> Setup
>   Find the top of material.
>   Check that the vise is square.
>   Center the probe stylus.
>
> JT
>
> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Optoisolater timings (was: Z axis stepper gradually losing position)

[Gene Heskett]

On Monday 14 December 2015 19:11:49 Jerry Scharf wrote:

> Hi,
>
> Just did a super quick google search and came up with a fairchild
> optocoupler hcpl2530 that will do 1Mbps. ~1.80 USD quantity 1.
> Isolation to 480v and good common mode rejection. There are a number
> of devices in similar and better speeds.
>
> That's not anywhere near the top speed for laser/detector systems,
> which now run to 100Gbps and beyond.
>
> opto stuff is so much cheaper than it used to be. The combination of
> insane laser volume and the demand for ultra speed detectors have made
> fast stuff really cheap.
>
> jerry
>
I was wondering if faster stuff was filtering down into the afordable 
category in the last decade,  But only 480 volt isolation? that would 
have to be mesa isolated on the same substrate, edge emitting diodes 
facing edge sensitive transistors. I think it depends on the environment 
if thats enough isolation.  With noise from higher speed/volatge stepper 
drivers nearby, I'd be a tad nervous.

> On Mon, Dec 14, 2015 at 1:57 PM, Gene Heskett  
wrote:
> > On Monday 14 December 2015 16:01:26 Ben Potter wrote:
> > > > Note that those setup and hold times are relative to the riseing
> > > > edge of
> > >
> > > the (step?) pulse, and the next line is not so specific, but I
> > > expect it needs to be checked by a dual trace scope for both
> > >
> > > > conditions
> > >
> > > I'm very tempted to pull the G540 from the router and rig up a
> > > test bench test to see if I can get my head around why this is
> > > happening. Might get time over christmas.
> > >
> > > Would be nice to know why inverting the step output works for me,
> > > rather than 'it just does' I'm starting to suspect that the 5i25
> > > obeys the set timings, whereas mach on a parallel port uses them
> > > as a minimum guide, and frequently exceeds them.
> > >
> > > > > I have no additional opto-isolation in that path - I believe
> > > > > that the G540 uses fast opto's on all the parallel port pins
> > > > > (from the manual, I'm sure there was a post on cnczone
> > > > > detailed the choice of isolater somewhere)
> > > >
> > > > Thanks for that , so it would have been DIRSETUP/DIRHOLD that I
> > > > was
> > >
> > > concerned with.
> > >
> > > I managed to dig out the thread where Mariss of Gecko was talking
> > > about opto circuits.
> > > http://www.cnczone.com/forums/general-cnc-machine-related-electron
> > >ics/ 23216- optoisolator-circuit.html
> > >
> > > Posts #2 and #6 are particularly interesting (not sure on
> > > cross-post etiquette here), and possibly give a hint as to the
> > > root cause of my problem.
> > >
> > > > > 
[...]
Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Some mill pix are at:
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Soft starting my mills spindle supply

[Gene Heskett]

On Monday 14 December 2015 20:51:46 andy pugh wrote:

> > As I reported, I have 4 of them coming.
>
> The forcibly guided relay for mine arrived today, so I finished
> assembling the PSU and then drew a schematic of what I ended up with.
>
> I am using the physical relay to ensure that I can't possibly power
> the system up with the discharge resistor in circuit. So, if the
> discharge contacts on the relay weld closed, the input SSR can't be
> energised.
> I ended up with a 6-pole relay. A 2-pole NO/NC relay would have
> worked, though.
>
I have some 24 volt coil 2 and 3pdt ice cubes that I will see about 
incorporation into my circuit, if I don't use the night lights.  They 
are slow, very slow, probably 10+ minutes to render it harmless, but 
like a piece of steel pulling on warped wood, never quit pulling.  
Unless they burn out that is.  I do have time to wait until I've no more 
time left. :)

> 620R is actually a bit high for the soft-start resistor. It seems
> about right for the discharge resistor.

I would say so, but wattage should be adequate. I didn't catch your 
voltage, but you know ohms law as well as I.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Some mill pix are at:
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Soft starting my mills spindle supply

[Gene Heskett]

On Monday 14 December 2015 20:51:46 andy pugh wrote:

> > As I reported, I have 4 of them coming.
>
> The forcibly guided relay for mine arrived today, so I finished
> assembling the PSU and then drew a schematic of what I ended up with.
>
> I am using the physical relay to ensure that I can't possibly power
> the system up with the discharge resistor in circuit. So, if the
> discharge contacts on the relay weld closed, the input SSR can't be
> energised.
> I ended up with a 6-pole relay. A 2-pole NO/NC relay would have
> worked, though.
>
> 620R is actually a bit high for the soft-start resistor. It seems
> about right for the discharge resistor.

I'll use that 51x200 watter, basically because thats what I have. I may 
give some thought toward using another to bring in a bleeder, but that 
would have to be on the DC side independent of the AC.  The concern 
there would be making sure it shuts off once triggered.  I'd have to 
give some thought to ways to assure that, such that it could not be 
restarted until it was off.  Or just use two 7 watt night lights in 
which case I'd have a pilot light of sorts, which would also be a 
seriously slow bleeder. Just one looked ok, but did not survive very 
many motor dirction reversals due to the voltage spike on the caps that 
created. 2 in series should last till the rapture... I've such a setup 
on the x10 circuit that runs my evening front deck lights, been there 
since 2008. No lamp failures.



I should probably take this opportunity to clarify my polishing of the 
E-Core laminations in that contactor, which silenced it.

As I'm aware of why its laminated in the first place, the motions against 
the sandpaper were always along the length of the stack, never across it 
so as not to smear the metal of one lamination over to an adjacent one, 
thereby creating an eddy current short.  That would raise the losses and 
create heating in the E-Core. From the almost vanishing temp rise I 
observed in the hour it took to make and eat our dinner, I believe I was 
successfull, as the core rise was about what one would expect would 
radiate inward from the coil form itself. IOW, the dark line of varnish 
between the laminations should never be bridged for any reason.  Taking 
a file to do that would almost certainly be a no-no for that reason.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Some mill pix are at:
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[John Thornton]

http://gnipsel.com/files/emc/probing.zip

On 12/14/2015 7:08 AM, Sarah Armstrong wrote:
> send cradeks probe stuff , not seen them they may be better
>
>
> On 14 December 2015 at 13:03, John Thornton  wrote:
>
>> Just looking at the probe routines in the samples and I find a couple of
>> surface mapping routines and a subroutine probe-hole.ngc with no
>> comments so not sure what it does. Tom just shared Cradek's probe
>> routines so I'll look at them for a bit.
>>
>> JT
>>
>> On 12/14/2015 6:41 AM, Sarah Armstrong wrote:
>>> it looks as if it's the same package you have looked at . done by the
>> guys
>>> over on the russian site
>>> theirs some probe stuff in the ngc folder .
>>>
>>> i have some too that might help , i'll dig them and emails shortly all
>>> being well
>>>
>>> On 14 December 2015 at 12:32, John Thornton  wrote:
>>>
 Crumb, I hit delete on your reply and it does not show up in the trash
 folder... which probe screen are you talking about?

 JT

 On 12/14/2015 6:02 AM, John Thornton wrote:
> With a probe on the way and after viewing a few probe screens which
>> seem
> to all be way to complicated for the job it made me wonder what
> practical probing routines people would actually use on a mill to
> machine parts with. I came up with a few but having never probed a part
> I'm looking for input from those that have probes now.
>
> Measuring a part.
> Measure a hole.
> Measure a pocket.
>
> Re-Machining
> Locate a hole.
>
> Setup
> Find the top of material.
> Check that the vise is square.
> Center the probe stylus.
>
> JT
>
>
>> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


>> --
 ___
 Emc-users mailing list
 Emc-users@lists.sourceforge.net
 https://lists.sourceforge.net/lists/listinfo/emc-users

>>>
>>
>>
>> --
>> ___
>> Emc-users mailing list
>> Emc-users@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>
>


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[Sarah Armstrong]

send cradeks probe stuff , not seen them they may be better


On 14 December 2015 at 13:03, John Thornton  wrote:

> Just looking at the probe routines in the samples and I find a couple of
> surface mapping routines and a subroutine probe-hole.ngc with no
> comments so not sure what it does. Tom just shared Cradek's probe
> routines so I'll look at them for a bit.
>
> JT
>
> On 12/14/2015 6:41 AM, Sarah Armstrong wrote:
> > it looks as if it's the same package you have looked at . done by the
> guys
> > over on the russian site
> > theirs some probe stuff in the ngc folder .
> >
> > i have some too that might help , i'll dig them and emails shortly all
> > being well
> >
> > On 14 December 2015 at 12:32, John Thornton  wrote:
> >
> >> Crumb, I hit delete on your reply and it does not show up in the trash
> >> folder... which probe screen are you talking about?
> >>
> >> JT
> >>
> >> On 12/14/2015 6:02 AM, John Thornton wrote:
> >>> With a probe on the way and after viewing a few probe screens which
> seem
> >>> to all be way to complicated for the job it made me wonder what
> >>> practical probing routines people would actually use on a mill to
> >>> machine parts with. I came up with a few but having never probed a part
> >>> I'm looking for input from those that have probes now.
> >>>
> >>> Measuring a part.
> >>>Measure a hole.
> >>>Measure a pocket.
> >>>
> >>> Re-Machining
> >>>Locate a hole.
> >>>
> >>> Setup
> >>>Find the top of material.
> >>>Check that the vise is square.
> >>>Center the probe stylus.
> >>>
> >>> JT
> >>>
> >>>
> >>
> --
> >>> ___
> >>> Emc-users mailing list
> >>> Emc-users@lists.sourceforge.net
> >>> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>
> >>
> >>
> --
> >> ___
> >> Emc-users mailing list
> >> Emc-users@lists.sourceforge.net
> >> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>
> >
> >
>
>
>
> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>



-- 

The information contained in this message is confidential and is intended
for the addressee only. If you have received this message in error or there
are any problems please notify the originator immediately. The unauthorised
use, disclosure, copying or alteration of this message is strictly
forbidden. This mail and any attachments have been scanned for viruses
prior to leaving the RcTechnix network. RcTechnix will not be liable for
direct, special, indirect or consequential damages arising from alteration
of the contents of this message by a third party or as a result of any
virus being passed on.

RcTechnix reserves the right to monitor and record e-mail messages being
sent to and from this address for the purposes of investigating or
detecting any unauthorised use of its system and ensuring effective
operation.

(c) RcTechnix
--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[John Thornton]

Just looking at the probe routines in the samples and I find a couple of 
surface mapping routines and a subroutine probe-hole.ngc with no 
comments so not sure what it does. Tom just shared Cradek's probe 
routines so I'll look at them for a bit.

JT

On 12/14/2015 6:41 AM, Sarah Armstrong wrote:
> it looks as if it's the same package you have looked at . done by the guys
> over on the russian site
> theirs some probe stuff in the ngc folder .
>
> i have some too that might help , i'll dig them and emails shortly all
> being well
>
> On 14 December 2015 at 12:32, John Thornton  wrote:
>
>> Crumb, I hit delete on your reply and it does not show up in the trash
>> folder... which probe screen are you talking about?
>>
>> JT
>>
>> On 12/14/2015 6:02 AM, John Thornton wrote:
>>> With a probe on the way and after viewing a few probe screens which seem
>>> to all be way to complicated for the job it made me wonder what
>>> practical probing routines people would actually use on a mill to
>>> machine parts with. I came up with a few but having never probed a part
>>> I'm looking for input from those that have probes now.
>>>
>>> Measuring a part.
>>>Measure a hole.
>>>Measure a pocket.
>>>
>>> Re-Machining
>>>Locate a hole.
>>>
>>> Setup
>>>Find the top of material.
>>>Check that the vise is square.
>>>Center the probe stylus.
>>>
>>> JT
>>>
>>>
>> --
>>> ___
>>> Emc-users mailing list
>>> Emc-users@lists.sourceforge.net
>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>>
>> --
>> ___
>> Emc-users mailing list
>> Emc-users@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>
>


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Z axis stepper gradually losing position (opto coupler speed)

[Gene Heskett]

On Sunday 13 December 2015 14:56:11 Karlsson & Wang wrote:

> > ...
> > I take it you do not have any opto-isolation in those 3 paths.  That
> > 700 ns is pushing an opto's ability to switch that fast.  The BoB I
> > used was all opto, and I was warned about its speed by someone
> > (Steve Stallings?) on this list.
> > ...
>
> Yes opto couplers are not very fast, I think around a few hundred
> kilobits per second could be expected for opto couplers if used for
> UART, obviously there have to be some margin to unless pushing the
> limit is necessary.
>
> Nicklas Karlsson

I have driven them in a 2M542 at as high as 360 kilobaud, just a motor 
laying on the table but for everyday work, would not trust them 100% 
above 175 kilobaud.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Some mill pix are at:
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Soft starting my mills spindle supply

[Gene Heskett]

On Sunday 13 December 2015 16:39:16 andy pugh wrote:

> On 13 December 2015 at 11:01, Gene Heskett  wrote:
> >> Feed the cap bank through a resistor.
> >> Use a (cheap $5) solid state relay to bypass that resistor when
> >> LinuxCNC is turned on.
> >
> > I had largely discounted that idea because the first cycle surge is
> > likely high enough to fuse a 40 amp Crydom. It trips a 20 amp
> > service breaker instantly when its master switch is closed. That
> > would also be complicated by needing a high side drive for it.
>
> The relay won't see the surge, because what the relay does is bypass
> the surge absorbing resistor.
>
> The relay would go on the AC input side, so you would only need one.
>
> You don't need a "high side driver", you need a 5V signal from
> LinuxCNC.

I got that grokked finally Andy, so I just ordered 4 of them, 40 a, 480 
volt from MPJones, a tad over a $50 bill by USPS.  Now to find a pair of 
uncommitted BoB pins. I'll keep one for a spare, but the third one will 
replace the ice cube I am controlling the vacuum cleaner with. I'll use 
one to switch the line, one to bypass the resistor in a few seconds, and 
one to switch the vacuum.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Some mill pix are at:
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Probe

[Viesturs Lācis]

2015-12-14 0:51 GMT+02:00 Andrew :
> 2015-12-14 0:41 GMT+02:00 John Thornton :
>
>> I saw that on in my search. Looks like a nice one, wonder where he is from?
>>
>> "*Hardened steel touch probe with rubby stylus for CNC machines*"
>
>
> Lithuania
> Free worldwide shipping though. And best offer available


Andrew, could you, please, share a link to his ebay store or that
particular listing? I must be dumb not to find it...

Viesturs

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Probe

[andy pugh]

On 14 December 2015 at 17:51, Jack Coats  wrote:
> http://stores.ebay.com/imsrv

That seems to be in Michigan.

Lithuania would suit Viesturs rather better, I suspect.


-- 
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Probe

[Viesturs Lācis]

Thanks, I should clarify - not that dumb to miss that link, but still
looking for _ebay_ store.

Viesturs


2015-12-14 21:07 GMT+02:00  :
> http://kurokesu.com/main/
>
>
> -Original Message-
> From: Viesturs Lācis [mailto:viesturs.la...@gmail.com]
> Sent: Monday, December 14, 2015 9:41 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Probe
>
> 2015-12-14 0:51 GMT+02:00 Andrew :
>> 2015-12-14 0:41 GMT+02:00 John Thornton :
>>
>>> I saw that on in my search. Looks like a nice one, wonder where he is
> from?
>>>
>>> "*Hardened steel touch probe with rubby stylus for CNC machines*"
>>
>>
>> Lithuania
>> Free worldwide shipping though. And best offer available
>
>
> Andrew, could you, please, share a link to his ebay store or that particular
> listing? I must be dumb not to find it...
>
> Viesturs
>
> 
> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
> --
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Z axis stepper gradually losing position

[Gene Heskett]

On Sunday 13 December 2015 14:39:19 Ben Potter wrote:

> > > When going through my testing for this the first time I cranked
> > > all 4 settings up to 10,000 - the problem still occurred. After I
> > > tried inverting the output I slowly stepped them back down - for
> > > my G540 I settled on 700/700/2000/2000.
> >
> > The Gecko 540 is not in the charts of our wiki, darnit. What is
> > there
>
> isn't even that fast. See:
>
> Yeah, I've thought about adding it a couple of times - but would want
> to do some more... intense testing before adding my timings there.
>
Note that those setup and hold times are relative to the riseing edge of 
the (step?) pulse, and the next line is not so specific, but I expect it 
needs to be checked by a dual trace scope for both 
conditions  .
> > 
> >
> > I take it you do not have any opto-isolation in those 3 paths.  That
> > 700
>
> ns is pushing an opto's ability to switch that fast.  The BoB I used
> was all opto, and I was warned about its speed by someone (Steve
> Stallings?) on this list.

> I don't recall which channel now, but I had to remove one of 
> > them
>
> and jumper across it. I think there are probably faster opto's about,
> but what I saw on the scope just wasn't up to getting the job done.
> All the loads that
>
> > BoB see's are already isolated, so I wasn't terribly concerned about
>
> losing one stage of isolation.
>
> I have no additional opto-isolation in that path - I believe that the
> G540 uses fast opto's on all the parallel port pins (from the manual,
> I'm sure there was a post on cnczone detailed the choice of isolater
> somewhere)
>
> To clarify, the figures I gave were in the format
> DIRSETUP/DIRHOLD/STEPLEN/STEPSPACE.
>
Thanks for that , so it would have been DIRSETUP/DIRHOLD that I was 
concerned with.

> Gecko give their recommendations on timings for the drive here:
> http://www.geckodrive.com/geckodrive-step-motor-drives/g540.html
>
> Those indicate 2000 nS for '0' on-time, 1000 nS for '1' on-time, 200
> nS for direction setup and hold. So it looks like I'm just within
> their recommendations on step length.

And that gives you far finer tools to tune with than software stepping 
ever will.  There may better interfaces than the 5i25, but for us 
stepper people, its the cats meow.  Not bulletproof on its inputs, I 
didn't have a good enough grounding setup wrapped around my G0704, and 
apparently blew the input I was using for a probe.

I don't know as Peter could tell me which chip to replace to rescue it. I 
AM a C.E.T. and in my dayjob before I retired in 2002/6/30, I could have 
done it easily, but at 81, my hands aren't as steady as they once were.

> I'm hooked up to a 5i25 instead of a parport though.
>
> > All my drivers are just 3 types, 2M542's, 2m860 and Pico pwm-servo's
> > for 2 of the 3 spindles at my place.  And I'm not pushing any of
> > them that
>
> fast.  But because of that slow BoB, ISTR I am running dir setup and
> dir hold about 1.5x longer than the wiki shows for the LeadShines.  So
> my experience is not > with a wide range of drivers, but I will no
> longer consider opto-isolated BoB's because everything I have is
> already isolated. Best BoB IMO, 10ns response times, but its been
> taken down, is the cnc4pc C1G that I have 2 of.  What he > is selling
> now is NOT the versions I have. Everything on mine has an led tally,
> which simplifies troubleshooting considerably.
>
> > Also, generally, where you have the choice of commonizing the +
> > terminal
>
> of a driver loads input, you are far better off doing that, and having
> the BoB pull it to ground as the pulldown in most TTL circuits is much
> more robust. > Having the reverse setup, where the - terminals are
> commonized, is generally NOT a good idea due to a lesser amount of
> pullup power to light up the opto in the drivers own input.
>
> I've gone to using mesa cards for pretty much all my interface as far
> as possible, I've had odd issues with Gecko and Leadshine drives, I've
> managed to work around them so far. The industrial drives I have used
> have generally behaved better. Since the machines I'm converting seem
> to be getting larger, I thankfully get to use servos more than
> steppers these days.
>
> The one I haven't tried yet, but would be curious to see if anyone has
> comments on is the Argon or Ion from Granite Devices.
>
> Ben

I can't comment based on experience with them so I won't, Ben.  Other 
than to say that 98% of the opto stuff out there, will need a pulse in 
excess of 1 microsecond on, and often pushing 2 u-s to turn off. I 
understand there are some Gas based optos about, but they'd have a 
serious effect on a BoB's price.  One could turn a $15 BoB into a $100 
BoB pretty fast.

However, one must bear in mind that when looking at it with a scope, we 
are watching the voltage, and in opto stuff, 

Re: [Emc-users] Probe

[linuxcnc]

http://kurokesu.com/main/


-Original Message-
From: Viesturs Lācis [mailto:viesturs.la...@gmail.com] 
Sent: Monday, December 14, 2015 9:41 AM
To: Enhanced Machine Controller (EMC)
Subject: Re: [Emc-users] Probe

2015-12-14 0:51 GMT+02:00 Andrew :
> 2015-12-14 0:41 GMT+02:00 John Thornton :
>
>> I saw that on in my search. Looks like a nice one, wonder where he is
from?
>>
>> "*Hardened steel touch probe with rubby stylus for CNC machines*"
>
>
> Lithuania
> Free worldwide shipping though. And best offer available


Andrew, could you, please, share a link to his ebay store or that particular
listing? I must be dumb not to find it...

Viesturs


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Practical Probing Routines

[Viesturs Lācis]

2015-12-14 14:32 GMT+02:00 John Thornton :
> Crumb, I hit delete on your reply and it does not show up in the trash
> folder... which probe screen are you talking about?


Andy posted this link (if you were asking for it):
https://forum.linuxcnc.org/forum/49-basic-configuration/29187-work-with-probe?limitstart=0

Viesturs

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Probe

[Jack Coats]

On Mon, Dec 14, 2015 at 11:41 AM, Viesturs Lācis 
wrote:

> Hardened steel touch probe with rubby stylus for CNC machines


http://stores.ebay.com/imsrv

Is where I saw several different sizes.


-- 
><> ... Jack

The Four Boxes of Liberty - "There are four boxes to be used in the defense
of liberty: soap, ballot, jury and ammo. Please use in that order."
"Whatever you do, work at it with all your heart"... Colossians 3:23
"Anyone who has never made a mistake, has never tried anything new." -
Albert Einstein
"You don't manage people; you manage things. You lead people." - Admiral
Grace Hopper, USN

"The most dangerous phrase in the language is, We’ve always done it this
way"-- Admiral Grace Hopper, USN
"Tell me and I forget. Teach me and I remember. Involve me and I learn." -
Ben Franklin
--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Optoisolater timings (was: Z axis stepper gradually losing position)

[Gene Heskett]

On Monday 14 December 2015 16:01:26 Ben Potter wrote:

> > Note that those setup and hold times are relative to the riseing
> > edge of
>
> the (step?) pulse, and the next line is not so specific, but I expect
> it needs to be checked by a dual trace scope for both
>
> > conditions
>
> I'm very tempted to pull the G540 from the router and rig up a test
> bench test to see if I can get my head around why this is happening.
> Might get time over christmas.
>
> Would be nice to know why inverting the step output works for me,
> rather than 'it just does' I'm starting to suspect that the 5i25 obeys
> the set timings, whereas mach on a parallel port uses them as a
> minimum guide, and frequently exceeds them.
>
> > > I have no additional opto-isolation in that path - I believe that
> > > the G540 uses fast opto's on all the parallel port pins (from the
> > > manual, I'm sure there was a post on cnczone detailed the choice
> > > of isolater somewhere)
> >
> > Thanks for that , so it would have been DIRSETUP/DIRHOLD that I was
>
> concerned with.
>
> I managed to dig out the thread where Mariss of Gecko was talking
> about opto circuits.
> http://www.cnczone.com/forums/general-cnc-machine-related-electronics/
>23216- optoisolator-circuit.html
>
> Posts #2 and #6 are particularly interesting (not sure on cross-post
> etiquette here), and possibly give a hint as to the root cause of my
> problem.
>
> > > 
> >
> > And that gives you far finer tools to tune with than software
> > stepping
>
> ever will.  There may better interfaces than the 5i25, but for us
> stepper people, its the cats meow.  Not bulletproof on its inputs, I
> didn't have a good enough > grounding setup wrapped around my G0704,
> and apparently blew the input I was using for a probe.
>
> > I don't know as Peter could tell me which chip to replace to rescue
> > it. I
>
> AM a C.E.T. and in my dayjob before I retired in 2002/6/30, I could
> have done it easily, but at 81, my hands aren't as steady as they once
> were.
>
> They do pretty nicely on servo stuff too - I have a 5i25 on the
> (servo) bridgeport, the (stepepr) lathe was converted earlier, and
> that has a 5i20 on.
>
> > I can't comment based on experience with them so I won't, Ben. 
> > Other than
>
> to say that 98% of the opto stuff out there, will need a pulse in
> excess of 1 microsecond on, and often pushing 2 u-s to turn off. I
> understand there are
>
> > some Gas based optos about, but they'd have a serious effect on a
> > BoB's
>
> price.  One could turn a $15 BoB into a $100 BoB pretty fast.
>
> From the thread above it looks like Gecko use the HCPL-2531 in at
> least some of their drives - price of $0.87 per 1k doesn't look too
> bad for a fast dual channel opto.
>
> > However, one must bear in mind that when looking at it with a scope,
> > we
>
> are watching the voltage, and in opto stuff, voltage doesn't mean near
> as much as actually measuring the current.  Why?  Because when the
>
> > driving led in the opto goes out, which it might do at 1.85 volts or
> > as high as 2.4 volts, the load is gone, leaving the voltage to decay
>
> toward (which ever rail its headed for) at a very leasurely rate.
>
> > Thats a fancy, CMA way to say the scope is lieing to you.  So I tend
> > to
>
> look at the decay with an eye toward seeing if I can define that point
> where the down (up?)ward curve changes to a slower rate, then make the
> "on time" timing > measurements to that point. That can be a difficult
> point to define even for me, and I've "had a scope probe in one hand"
>
> > for 64 years. 64 years ago it was a 5mhz Hickock, today I have
> > 100MHZ dual
>
> trace analog, and 200mhz dual trace digitals to go poking around with.
>
> > Cheers, Gene Heskett
>
> Good to know, I have a rescued tektronix scope which I rarely get to
> use. Hints on those things that are only learned through experience
> are always appreciated.
>
> I suspect spotting most of the ways phase shift can trip you up even
> on simple circuits takes quite a bit of practice.
>
That, and ingenuity in figuring out how best to get at it with a probe.  
And sometimes you can't, you have to go well beyond and let experience 
guide one on figuring out what the heck is going on at the point of 
interest. I have even written software to excite the circuit, then asked 
it to play it back, then do a comparison of sent vs echo. In this case, 
a 4x4 fifo, used 2 wide for an 8 bite wide rubber buffer coupling in a 
video switcher, had one of the 2 4x4 fifo's that wasn't responding to 
the shift out command, about 2% of the time.  Called the switcher maker, 
who wanted $1500 a copy for the chip.  But I'm sneaky, I suspected it 
was an AMD product, called them, and they said yeah, we finally did get 
a JEDEC number for it, and its $2.10 a piece, how many do you want?  I 
took a mental inventory of how many were in it, and ordered 2 sticks, 
then told the GM there would be a COD package from AMD.  He had his 
usual litter of cows. 

Re: [Emc-users] Soft starting my mills spindle supply

[Gene Heskett]

On Sunday 13 December 2015 16:39:16 andy pugh wrote:

> On 13 December 2015 at 11:01, Gene Heskett  wrote:
> >> Feed the cap bank through a resistor.
> >> Use a (cheap $5) solid state relay to bypass that resistor when
> >> LinuxCNC is turned on.
> >
> > I had largely discounted that idea because the first cycle surge is
> > likely high enough to fuse a 40 amp Crydom. It trips a 20 amp
> > service breaker instantly when its master switch is closed. That
> > would also be complicated by needing a high side drive for it.
>
> The relay won't see the surge, because what the relay does is bypass
> the surge absorbing resistor.
>
> The relay would go on the AC input side, so you would only need one.
>
> You don't need a "high side driver", you need a 5V signal from
> LinuxCNC.

As I reported, I have 4 of them coming.  But always curious. after I got 
my lady settled in from her cataract surgery this morning. I went out 
and attached a line cord to the one I had out, and which had the .004" 
thick hard paper shim between the poles.  It darned near buzzed itself 
off the table when I plugged it in .

So I took the shim back out, a bit quieter but still had an audible buzz 
I could hear from anyplace in the garage.

I had noted a light film of rust on the E core faces, so I laid a worn 
piece of that 220 grit in a flat, and polished 75% of the rust away, 
noting that the center leg of the E was a thou or so lower than the 
outer legs. I sanded until I could begin to see a bit of clean steel 
thru the nearly black oxide coat on the center leg, and the outer legs 
were about 75% clean.  Put it back together, could not hear anything but 
a very low level hum with an ear on it.

Blew a couple feet of the concrete floor clean so if it blew up while I 
was back in here making preps for dinner, and left it plugged in for an 
hour.  Went back out, E core temp up 3 maybe 4 degrees F, coil maybe 10F 
warmer.  And still essentially dead silent.

Now I wonder if thats the secret to shutting all of them up, because I 
could easily tolerate 2 or 3 of those running if they'd run that quiet.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Some mill pix are at:
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Optoisolater timings (was: Z axis stepper gradually losing position)

[Ben Potter]

> Note that those setup and hold times are relative to the riseing edge of
the (step?) pulse, and the next line is not so specific, but I expect it
needs to be checked by a dual trace scope for both 
> conditions


I'm very tempted to pull the G540 from the router and rig up a test bench
test to see if I can get my head around why this is happening. Might get
time over christmas.

Would be nice to know why inverting the step output works for me, rather
than 'it just does' I'm starting to suspect that the 5i25 obeys the set
timings, whereas mach on a parallel port uses them as a minimum guide, and
frequently exceeds them.

> > I have no additional opto-isolation in that path - I believe that the
> > G540 uses fast opto's on all the parallel port pins (from the manual, 
> > I'm sure there was a post on cnczone detailed the choice of isolater
> > somewhere)

> Thanks for that , so it would have been DIRSETUP/DIRHOLD that I was
concerned with.

I managed to dig out the thread where Mariss of Gecko was talking about opto
circuits.
http://www.cnczone.com/forums/general-cnc-machine-related-electronics/23216-
optoisolator-circuit.html

Posts #2 and #6 are particularly interesting (not sure on cross-post
etiquette here), and possibly give a hint as to the root cause of my
problem.

> > 

> And that gives you far finer tools to tune with than software stepping
ever will.  There may better interfaces than the 5i25, but for us stepper
people, its the cats meow.  Not bulletproof on its inputs, I didn't have a
good enough > grounding setup wrapped around my G0704, and apparently blew
the input I was using for a probe.

> I don't know as Peter could tell me which chip to replace to rescue it. I
AM a C.E.T. and in my dayjob before I retired in 2002/6/30, I could have
done it easily, but at 81, my hands aren't as steady as they once were.

They do pretty nicely on servo stuff too - I have a 5i25 on the (servo)
bridgeport, the (stepepr) lathe was converted earlier, and that has a 5i20
on.

> I can't comment based on experience with them so I won't, Ben.  Other than
to say that 98% of the opto stuff out there, will need a pulse in excess of
1 microsecond on, and often pushing 2 u-s to turn off. I understand there
are 
> some Gas based optos about, but they'd have a serious effect on a BoB's
price.  One could turn a $15 BoB into a $100 BoB pretty fast.

>From the thread above it looks like Gecko use the HCPL-2531 in at least some
of their drives - price of $0.87 per 1k doesn't look too bad for a fast dual
channel opto. 

> However, one must bear in mind that when looking at it with a scope, we
are watching the voltage, and in opto stuff, voltage doesn't mean near as
much as actually measuring the current.  Why?  Because when the 
> driving led in the opto goes out, which it might do at 1.85 volts or   
> as high as 2.4 volts, the load is gone, leaving the voltage to decay
toward (which ever rail its headed for) at a very leasurely rate.

> Thats a fancy, CMA way to say the scope is lieing to you.  So I tend to
look at the decay with an eye toward seeing if I can define that point where
the down (up?)ward curve changes to a slower rate, then make the "on time"
timing > measurements to that point. That can be a difficult point to define
even for me, and I've "had a scope probe in one hand" 
> for 64 years. 64 years ago it was a 5mhz Hickock, today I have 100MHZ dual
trace analog, and 200mhz dual trace digitals to go poking around with.

> Cheers, Gene Heskett

Good to know, I have a rescued tektronix scope which I rarely get to use.
Hints on those things that are only learned through experience are always
appreciated.

I suspect spotting most of the ways phase shift can trip you up even on
simple circuits takes quite a bit of practice.

Thanks
Ben


--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Probe

[Andrew]

2015-12-14 21:21 GMT+02:00 Viesturs Lācis :

> Thanks, I should clarify - not that dumb to miss that link, but still
> looking for _ebay_ store.
>

Viesturs, there are no more probes listed right now.
Though yesterday it was available http://www.ebay.com/itm/151911730211
Apparently sold just recently.

Andrew
--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Probe

[Viesturs Lācis]

2015-12-14 22:51 GMT+02:00 Andrew :
> Viesturs, there are no more probes listed right now.
> Though yesterday it was available http://www.ebay.com/itm/151911730211
> Apparently sold just recently.

Thank you!

Viesturs

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users