[3space]

I too have the SX-3, purchased March 2103, and want computer-based spindle control (start/stop/direction/speed). Am I understanding correctly that the $99 board from LMS purports to do the job, but fails to deliver? Would I also need a new transformer? The installation guide describes a reasonably trivial installation process, yet this thread suggests otherwise. Further comments? Thx!

[rwskinner]

Nothing wrong with the LMS Board, it works fine. My problem is the G540 speed output is not real linear. You're able to map the speed using the speed calibration process but you have to use a temporary speed input to do so. I kind of wish Mach3 would allow you to enter the data points by hand. I inquired but Brian never responded.

Richard

[mattm55]

Update: ...on it's way...

I have a G540 connected to an SX3 and will order one tomorrow and then do a write w/pics to share. A giveback for all the help this forum has provided me. If anyone is doing an install, fell free to share as well. It helps.

Thanks, Matt

[mattm55]

Received the LMS Spindle Controller this past Friday. I will add my install to the build link I created for CNC'ing the SX3.

The install is with a G540 with 110v and I'll try to see what the Mach3 setup is as I go. If we need a video, I can try to do a small one if pics aren't sufficient. The install and simple wiring seem very straightforward. We'll see?

Matt


http://www.cnczone.com/forums/x3_sx3...l_build-4.html

[3space]

Received the LMS Spindle Controller this past Friday. I will add my install to the build link I created for CNC'ing the SX3.

http://www.cnczone.com/forums/x3_sx3...l_build-4.html

Hey Matt,

I'm likely going the same way as you've ray soon regarding the LMS SX-3 spindle control package, so I'm very interested to hear from you on this. I'll follow your build thread.

Thx!

[mrpackethead]

I'd like to get some spindle control on my SX-3. Mine currnetly has the digital setup, on it, and i'm running 240VAC. Would this kit work? Or any other suggestions.

[simila95]

I was back and forth about the LMS spindle control. CNC4pc also has this CNC4PC that i was looking at as i need to order some stuff from them anyway. I have a control box with vfd so assume it will work. Get a chance to fire yours up yet matt?

[mattm55]

Get a chance to fire yours up yet matt?

Not yet but it is on my next TODO. I will post the steps I used to install mine (build link) and if anyone needs more description/pics on something in particular, just let me know. I think I found a good mount position so far and had to stop and order some standoffs for mounting the PCB. Mine is 110v though....

Matt

[mattm55]

I was back and forth about the LMS spindle control. CNC4pc also has this CNC4PC that i was looking at as i need to order some stuff from them anyway. I have a control box with vfd so assume it will work. Get a chance to fire yours up yet matt?

Yes, I have it setup and working now. I will post more info, screenshots on the addition of the SCB later this week. So far the board, for $99, works as designed for my setup. I can now turn On/Off the spindle from Mach3 and change the spindle speed from Mach3. I think I would like to try the $599 motor/spindle combo too that is out there but for the cost, it does work.

Setup:
~G540 driver
~110v CNC
~homemade controller with Ethernet Smootstepper
~Mach3 w/SS config file

Matt

[rwskinner]

You didn't mention how well the speed control tracked? Did you have any issues getting the actual speed to be fairly close to the desired speed?

As I mentioned in my comments, using an external power supply, I found the LMS board to be very linear and pretty much on the money as far as desired speed and actual speed.
Where I found the issue, is neither of my G540's were close to being linear.

I tracked the Mach3 PWM output which was fine.
I tested the LMS board with external variable voltage power supply and it was fine.
I tested the voltage output of the G540 and it was no where near linear.

I also had this issue when the G540 was driving VFD's as well as the same oscillation during certain speed settings.
I never experienced this with the PMDX boards.

I sent several emails to Gecko explaining the problem and showing the graphs but never a response.

Richard

[mattm55]

You didn't mention how well the speed control tracked? Did you have any issues getting the actual speed to be fairly close to the desired speed?

I did get a chance to test a few different speeds from Mach3 to the spindle and they did correlate for my setup. Now I only tried 5 steps (300, 500, 700, 1000 & 1700). Give or take +/- 10-30 RPM's, they were pretty close. That was measured with my $13 laser tach from eBay. I did have to go back to the simple wiring to make sure at +5v I had 1700RPM spindle speed.

Good point on checking the G540 for a linear voltage output. I didn't think of that and will add that to my tests and report back.

EDIT: Here is what my voltage looks like based on RPM's.
Attachment 229484

Matt

[c45]

I also bought the 'CNC Spindle Control Upgrade Kit for SX3' from LMS and had a issue when installing it.
Because I already hat the pictures made for questioning LMS I will post this as a doku.
Attachment 249598
As you see I have the 230V edition for Europe because my machine is also a 230V version.
When I connected the kit to my SX3 Spindel driver (and did all the other things written in the manual) in the 'simplest configuration' like LMS adviced, the spindel was turning and I could revers the turning of the spindel. The only problem was that the spindel was turning all the time no matter if I connect 'start/stop' to GND. I thought I read this problem somwere else in a post. Asking LMS about that issue brought no solution. I think the are a harware store and not familiar with the guts of this device.
By the way, this is the connection on the SX3 driver board. First picture with original plug, second with the upgrade kit connected (you see mechanical it's fitting not 100%).
Attachment 249600 Attachment 249602
So I followed the 'start/stop' signal on the kit's board into the SX3 driver board (red wire). Electrically there was a pin switching from -0.7 to 4 Volts (maybe the GND was not realy Ground but you see a change).
This wasn't reaching any pin on the ATMEGA sitting on the Sieg SX3 dirver board.
Attachment 249604
Remove the big driver pcb and you can see:
Attachment 249606
The pin isn't connected at all from the factory. I don't know if they changed this on all new machines. Mine was purchaed in may 2014 and it was a 230V version.
So for safety reasons and for a first attempt (and I never remved it since) I soldered a 100 Ohm resistor into the gap and the start/stop was working.

After that I started to test the kit with my linuxcnc and a home brew breakout box. In my case the PWM for the spindle speed was ways out of exact revolution. Tested with a DC power supply it worked fine with the same linearity like the graph mattm55 posted here before. So the PWM from linuxcnc was set to 100Hz. Chageing that was no success. The speed was oscillating when setting slow values. So I made a filter to smoothen the curve.
Attachment 249608
Here you can see a PWM of 10V with a duty cycle of 10% going into the filter. The output on the 1K dummy load is 1V. The filter is rather slow, it takes 0.5s to go up to 1V but my spindle is slow, too.
The output in a closer look, some minor ripple, but O.K. for me and the kit, the oscillating was gone, everything worked fine. It seems that the kit don't like raw PWM.
Attachment 249610
Altogether in one string with the outbreak part it looks like this:
Attachment 249612
The OP's power supply not shown in the picture is 12V to reach the full 10V output. Also not shown is the driver of the optocoupler.

Here is a chart commanded speed vs. actual speed on my setup, also measured with a cheap chinese laser speed tach:
Attachment 249614

[rwskinner]

The start/stop does not work, you have to drop the control voltage to zero in order for the spindle to stop. Using a POT just turn it down to minimal position, using control from Mach issue a M5 as normal. I don't think I had to do a S0 command for it to stop, I believe the M5 did the trick.

Ah, just read the rest of your message. That is nice to know adding that bridge across those contacts fixed the start stop feature. Yes, definetly a better solution.

Richard

[mattm55]

That's great info and might help those looking for info on this board. I know when I looked, there wasn't much around. I purchased a MachTach and will be installing that on the mill to monitor the RPM's. I just got a little diverted with a a lathe purchase....

Keep the information coming...

Thanks, Matt