Re: [Emc-users] Modbus wiring

> > > > ISO7421 > > > > > > Now thats sweet, and a heck of a lot better thought out than the > > > last such chip I looked at a decade ago. Needs a 4 wire cable from > > > each direction, but I don't see as that as a problem other than > > > stealing the ground and 3.3 or 5 volts to run its side

Re: [Emc-users] Max acceleration/velocity (Limited by?)

As easy as traj max vel = sqr(VmaxX^2+VmaxY^2+VmaxZ^2) On Sun, 03 Apr 2016 16:54:45 -0500 Jon Elson wrote: > On 04/03/2016 11:14 AM, Nicklas Karlsson wrote: > > Then reading the configuration file I find there max acceleration and > > velocity is defined twice. They

Re: [Emc-users] Modbus wiring

On Sunday 03 April 2016 18:12:28 Nicklas Karlsson wrote: > > > ISO7421 > > > > Now thats sweet, and a heck of a lot better thought out than the > > last such chip I looked at a decade ago. Needs a 4 wire cable from > > each direction, but I don't see as that as a problem other than > > stealing

Re: [Emc-users] Modbus wiring

> > ISO7421 > > Now thats sweet, and a heck of a lot better thought out than the last > such chip I looked at a decade ago. Needs a 4 wire cable from each > direction, but I don't see as that as a problem other than stealing the > ground and 3.3 or 5 volts to run its side of it at both ends.

Re: [Emc-users] Max acceleration/velocity (Limited by?)

On 04/03/2016 11:14 AM, Nicklas Karlsson wrote: > Then reading the configuration file I find there max acceleration and > velocity is defined twice. They are defined in both [TRAJ] and [AXIS_?] > sections. > > Does the trajectory planner follow the limit in it's own section? In such > case what

Re: [Emc-users] Max acceleration/velocity (Limited by?)

On Sunday 03 April 2016 16:52:12 Nicklas Karlsson wrote: > > On Sun, Apr 3, 2016, at 12:14 PM, Nicklas Karlsson wrote: > > > Then reading the configuration file I find there max acceleration > > > and velocity is defined twice. They are defined in both [TRAJ] and > > > [AXIS_?] sections. > > > >

Re: [Emc-users] Max acceleration/velocity (Limited by?)

> On Sun, Apr 3, 2016, at 12:14 PM, Nicklas Karlsson wrote: > > Then reading the configuration file I find there max acceleration and > > velocity is defined twice. They are defined in both [TRAJ] and [AXIS_?] > > sections. > > I am reasonably certain that the TRAJ limits apply to the combined

Re: [Emc-users] Modbus wiring

On Sunday 03 April 2016 15:07:59 Nicklas Karlsson wrote: > ISO7421 Now thats sweet, and a heck of a lot better thought out than the last such chip I looked at a decade ago. Needs a 4 wire cable from each direction, but I don't see as that as a problem other than stealing the ground and 3.3

Re: [Emc-users] Modbus wiring

ISO7421 is two channel bidirectional, there are more of them with different configurations. On Sun, 3 Apr 2016 14:30:50 -0400 Gene Heskett wrote: > On Sunday 03 April 2016 14:10:04 Nicklas Karlsson wrote: > > > I tried opto isolators and they did not work without errors

Re: [Emc-users] Controller/machine resolution

> Floating-point numbers have a huge range due to the floating-point > nature, but the dynamic range is limited. The mantissa of an IEEE 754 > double-precision float (8 bytes) has a width of 52 bits (not counting > the sign). This gives 52/log2(10)=15.7 decimal digits of accuracy. For > linear

Re: [Emc-users] Modbus wiring

On Sunday 03 April 2016 14:10:04 Nicklas Karlsson wrote: > I tried opto isolators and they did not work without errors while > capacitive insulation barriers did. It was a suprise and I can't tell > why. I think most devices including opto have a limited dv/dt > tolerance. Damn, old wet ram

Re: [Emc-users] Modbus wiring

On Sunday 03 April 2016 13:36:23 Danny Miller wrote: > Well, if you have 2 differential wires with a simple optoisolator at > the far end, ground noise/ground loops would have no effect > whatsoever. You don't need a ground. There would be no place to put a > ground. There are no common-mode

Re: [Emc-users] Configuring TB6560 Stepper Drivers

> On Apr 3, 2016, at 7:32 AM, Valerio Bellizzomi wrote: > > so now you can retry my config problably this time with luck :-) HI Valerio, It was pretty forgiving on the timing settings - we used the Sherline defaults. Best, Jeshua Lacock Founder/Engineer <3DTOPO.com>

Re: [Emc-users] Controller/machine resolution

Hi all, I have to admit that I've not read the rest of the discussion, so please excuse if that has already been said. On 03.04.2016 19:09, Mark wrote: > On 04/03/2016 12:41 PM, Jon Elson wrote: >> On 04/03/2016 09:46 AM, Mark wrote: >>> That's why in this theoretical discussion I asked to >>>

Re: [Emc-users] Controller/machine resolution

On Sunday 03 April 2016 09:38:59 Mark wrote: > On 04/03/2016 09:28 AM, Dave Caroline wrote: > > A number is a number regardless of trailing 0's, no affect on > > accuracy or resolution. > > Where users do get it wrong though, is not understanding how path > > following has a tolerance. This is

Re: [Emc-users] Modbus wiring

I tried opto isolators and they did not work without errors while capacitive insulation barriers did. It was a suprise and I can't tell why. I think most devices including opto have a limited dv/dt tolerance. On Sun, 3 Apr 2016 12:36:23 -0500 Danny Miller wrote: >

Re: [Emc-users] Controller/machine resolution

On Sunday 03 April 2016 09:37:05 Mark wrote: > I understand that, but that doesn't really answer the question - what > determines the machine/controller resolution/precision, the machine > and electronics notwithstanding. If I set the G Code coordinates to > x.x is the resolution/accuracy

Re: [Emc-users] Modbus wiring

On Sunday 03 April 2016 09:35:04 Nicklas Karlsson wrote: [huge snip] > You could also read if there is something in the manual about a > shielded cable and how it should be connected. > > > Nicklas Karlsson Such information is not mentioned in my Chinglish manual. And thats troublesome too

Re: [Emc-users] Modbus wiring

Well, if you have 2 differential wires with a simple optoisolator at the far end, ground noise/ground loops would have no effect whatsoever. You don't need a ground. There would be no place to put a ground. There are no common-mode issues. The slave device's ground could be +300VDC above

Re: [Emc-users] Max acceleration/velocity (Limited by?)

On Sun, Apr 3, 2016, at 12:14 PM, Nicklas Karlsson wrote: > Then reading the configuration file I find there max acceleration and > velocity is defined twice. They are defined in both [TRAJ] and [AXIS_?] > sections. I am reasonably certain that the TRAJ limits apply to the combined motion of

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 12:41 PM, Jon Elson wrote: > On 04/03/2016 09:46 AM, Mark wrote: >> That's why in this theoretical discussion I asked to >> disregard the actual machine accuracy and presume you had >> the so-called perfect machine. What I was looking for was >> how precise/accurate/resolute the

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 09:46 AM, Mark wrote: > That's why in this theoretical discussion I asked to > disregard the actual machine accuracy and presume you had > the so-called perfect machine. What I was looking for was > how precise/accurate/resolute the controller would be. But, there is no "perfect

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 08:37 AM, Mark wrote: > I understand that, but that doesn't really answer the question - what > determines the machine/controller resolution/precision, the machine and > electronics notwithstanding. If I set the G Code coordinates to x.x is > the resolution/accuracy actually 0.1" or

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 07:48 AM, Mark wrote: > Friend of mine and I have had an email discussion going over the last > few days about movement precision, accuracy and resolution. > > Lets say there are three different G Code files, A, B and C. > > In file A, the coordinates are such: X x.x Y x.x > > In

[Emc-users] Max acceleration/velocity (Limited by?)

Then reading the configuration file I find there max acceleration and velocity is defined twice. They are defined in both [TRAJ] and [AXIS_?] sections. Does the trajectory planner follow the limit in it's own section? In such case what happen if [AXIS_?] limit is lower? Regards Nicklas

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 10:14 AM, Nicklas Karlsson wrote: >> On 04/03/2016 09:31 AM, Nicklas Karlsson wrote: Lets say there are three different G Code files, A, B and C. In file A, the coordinates are such: X x.x Y x.x In file B, the coordinates are such: X x.xx Y x.xx In

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 09:42 AM, Dave Caroline wrote: > we are all saying it makes NO difference how many trailing 0s you have > the accuracy is machine and its maths, see Andy's answer > > Dave Caroline It's a theoretical discussion, hence my usage of the theoretically perfect machine, which has no slop

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 09:55 AM, andy pugh wrote: > On 3 April 2016 at 14:47, Mark wrote: > >> Okay, now we're getting somewhere. Assuming the theoretically perfect >> machine, a commanded move in a straight line (keeping it >> simplified)would stop within >> >> x.x0" of

Re: [Emc-users] Controller/machine resolution

> On 04/03/2016 09:31 AM, Nicklas Karlsson wrote: > >> Lets say there are three different G Code files, A, B and C. > >> > >> In file A, the coordinates are such: X x.x Y x.x > >> > >> In file B, the coordinates are such: X x.xx Y x.xx > >> > >> In file C, the coordinates are such: X x.xxx Y

Re: [Emc-users] Controller/machine resolution

On 3 April 2016 at 14:47, Mark wrote: > Okay, now we're getting somewhere. Assuming the theoretically perfect > machine, a commanded move in a straight line (keeping it > simplified)would stop within > > x.x0" of it's commanded position, correct? Yes. Less

Re: [Emc-users] Configuring TB6560 Stepper Drivers

On Sat, 2016-04-02 at 18:00 -0600, jeshua wrote: > > On Mar 28, 2016, at 6:01 PM, Gene Heskett wrote: > > > > On Monday 28 March 2016 19:48:26 Gene Heskett wrote: > > > >> On Monday 28 March 2016 16:21:36 jeshua wrote: > On Mar 26, 2016, at 7:50 AM, Sarah Armstrong >

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 09:34 AM, andy pugh wrote: > On 3 April 2016 at 13:48, Mark wrote: > >> Using file A for example, with the coordinates only given with 0.1" >> precision, what exactly does the controller do? Does it actually work >> to 0.1" precision or does it work to

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 09:31 AM, Nicklas Karlsson wrote: >> Lets say there are three different G Code files, A, B and C. >> >> In file A, the coordinates are such: X x.x Y x.x >> >> In file B, the coordinates are such: X x.xx Y x.xx >> >> In file C, the coordinates are such: X x.xxx Y x.xxx >> >> For

Re: [Emc-users] Controller/machine resolution

we are all saying it makes NO difference how many trailing 0s you have the accuracy is machine and its maths, see Andy's answer Dave Caroline -- Transform Data into Opportunity. Accelerate data analysis in your

Re: [Emc-users] Controller/machine resolution

On 04/03/2016 09:28 AM, Dave Caroline wrote: > A number is a number regardless of trailing 0's, no affect on accuracy > or resolution. > Where users do get it wrong though, is not understanding how path > following has a tolerance. This is separate from the number and its > 0's but the speed of

Re: [Emc-users] Controller/machine resolution

I understand that, but that doesn't really answer the question - what determines the machine/controller resolution/precision, the machine and electronics notwithstanding. If I set the G Code coordinates to x.x is the resolution/accuracy actually 0.1" or is it 0.01" or 0.001" or something

Re: [Emc-users] Modbus wiring

> > Gene Heskett wrote: > > > On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote: > > > > > I had SERIOUS problems with my X200 VFD and RS485 bus- I > > > > > "mostly" fixed it. > > > > > > > > > > Here's the thing- yes, RS485 is differential, but the VFD is > > > > >

Re: [Emc-users] Controller/machine resolution

On 3 April 2016 at 13:48, Mark wrote: > Using file A for example, with the coordinates only given with 0.1" > precision, what exactly does the controller do? Does it actually work > to 0.1" precision or does it work to moreprecision, vis-a-vis when > making moves? It will

Re: [Emc-users] Controller/machine resolution

> Lets say there are three different G Code files, A, B and C. > > In file A, the coordinates are such: X x.x Y x.x > > In file B, the coordinates are such: X x.xx Y x.xx > > In file C, the coordinates are such: X x.xxx Y x.xxx > > For simplicity's sake, no Z axis and the units are inches. >

Re: [Emc-users] Controller/machine resolution

A number is a number regardless of trailing 0's, no affect on accuracy or resolution. Where users do get it wrong though, is not understanding how path following has a tolerance. This is separate from the number and its 0's but the speed of how you can change direction. see

Re: [Emc-users] Modbus wiring

On Sunday 03 April 2016 06:21:38 Nicklas Karlsson wrote: > On Sat, 2 Apr 2016 11:34:25 -0400 > > Gene Heskett wrote: > > On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote: > > > > I had SERIOUS problems with my X200 VFD and RS485 bus- I > > > > "mostly" fixed it. > > >

Re: [Emc-users] Controller/machine resolution

http://linuxcnc.org/docs/2.7/html/gcode/overview.html#_number JT On 4/3/2016 7:48 AM, Mark wrote: > Friend of mine and I have had an email discussion going over the last > few days about movement precision, accuracy and resolution. > > Lets say there are three different G Code files, A, B and C.

[Emc-users] Controller/machine resolution

Friend of mine and I have had an email discussion going over the last few days about movement precision, accuracy and resolution. Lets say there are three different G Code files, A, B and C. In file A, the coordinates are such: X x.x Y x.x In file B, the coordinates are such: X x.xx Y x.xx

Re: [Emc-users] Nets and parameters in *.hal files

On Sun, 3 Apr 2016 11:54:16 +0100 andy pugh wrote: > On 3 April 2016 at 11:47, Nicklas Karlsson > wrote: > > To load it and look at the list halcmd print work although to get something > > useful from it is a little bit harder but once the

Re: [Emc-users] Nets and parameters in *.hal files

On 3 April 2016 at 11:47, Nicklas Karlsson wrote: > To load it and look at the list halcmd print work although to get something > useful from it is a little bit harder but once the information is there it is > solvable. The -s switch might make processing the data

Re: [Emc-users] Nets and parameters in *.hal files

On Fri, 1 Apr 2016 17:51:23 -0500 Jeff Epler wrote: > No, there is no way to take a component and find out the pins > and parameters it will create, except for loading it and looking at the > lists halcmd can print. To load it and look at the list halcmd print work

Re: [Emc-users] Modbus wiring

On Sat, 2 Apr 2016 11:34:25 -0400 Gene Heskett wrote: > On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote: > > > > I had SERIOUS problems with my X200 VFD and RS485 bus- I "mostly" > > > fixed it. > > > > > > Here's the thing- yes, RS485 is differential, but the VFD