Messages

271

General Mach Discussion / Re: spindle speed via modbus

« on: November 09, 2010, 08:20:04 AM »

Hi,

Have a look at this thread. It shows how it was done for a Hitachi VFD.

http://www.machsupport.com/forum/index.php/topic,16316.0.html

You will need to look at your manual to find the appropriate registe numbers.

Cheers,



Peter.

272

General Mach Discussion / Re: spindle speed via modbus

« on: November 09, 2010, 07:55:11 AM »

Hi,

Yes, if your inverter can communicate via Modbus.

Cheers,

Peter.

273

SmoothStepper USB / Re: If you have noise issues this might be worth a try

« on: November 08, 2010, 06:31:05 PM »

Hi,

To desolder the components R5 and C4, lay the tip of the soldering iron along side R4 (in between R4 and C5 is best).  Most iron tips will be large enough to bridge both ends of the component.  If not, alternate the tip back and forth between both ends in a rocking motion. If necessary you can also add some solder to help it reflow.

When you see that both ends are molten, wipe the component off the board with the iron.

Then do the same for C5. Note the capacitor will take a little longer, but the process is the same.

A lot of people think that you need a really fine tipped iron for SMT work. The problem with a really fine tip is that the heat gets sucked out of it too easily.

For most of my work I use a 1/8" chisel tip.

Cheers,

Peter.

274

Modbus / Re: Hitachi X200

« on: October 29, 2010, 04:32:05 PM »

Hi,

Glad to see it is working.

Do you want to post the brain so that other owners of a Hitachi  can use it?

Cheers,

Peter.

275

Modbus / Re: Hitachi X200

« on: October 28, 2010, 11:38:11 PM »

Hi,

I just uploaded a presentation I did recently at the CNC BBQ in Adelaide. It may provide an overview on interfacing Mach3 to Modbus devices via brains.
http://www.machsupport.com/forum/index.php/topic,16347.html

Cheers,

Peter.

276

Modbus / Modbus Presentation

« on: October 28, 2010, 11:34:50 PM »

Hi All,

A week or two ago I did a talk on Modbus and MAch3 at the Adelaide CNC BBQ.

Attached are my presentation slides that some may find useful.

If the administrators feel that it has enough merit, they could put it in the members doc area.

enjoy.

Peter.

277

Modbus / Re: Hitachi X200

« on: October 28, 2010, 10:29:08 PM »

Ok, good.

I'd also try communicating at 19200.

What you now need to do is set up a number of modbus comms configurations.

setup a cfg say #1,  to write two coils starting at address 0001h

This will allow you to start and stop the spindle in both forward and reverse



setup another cfg, say #2 to write the holding register 0002H
This will allow you to set the inverter frequency.


Once these are setup, Mach will be continuously writing these coils and holding registers to the VFD.


Now you need to set the values. For that you need to write a brain. In the brain you will take the set spindle speed DRO put it through a formula and then write the value to the Modbus cfg#2 data buffer.  
The formula will scale the speed so that it will send 4000 to the VFD when your maximum spindle speed is asked for. If your max spindle speed was say, 24,000 rpm the formula would be;  

V = Set Spindle speed DRO /(max spindle speed/4000)
V = Set Spindle speed DRO /6


As Mach3 is sending this buffer to the VFD, it will receive the Frequency value.


You then need to write the Spindle ON LED  and the Spindle Direction LED to CFG#1

That should do it.


You should look at the video tutorials on brains and serial Plugin Modbus.

Cheers,

Peter.

278

General Mach Discussion / Re: Hardinge CHNC retrofit. ASD drive (old school) and threading...

« on: October 28, 2010, 10:09:34 PM »

Hi,

Yes, what you are suggesting will be fine.

When, threading, Mach3 does not vary the spindle speed, it varies the Z axis feedrate to match the speed of the spindle.

So, if the spindle slows slightly, the Z axis will also slow to ensure that the thread pitch being cut is maintained.

What Mach3 does need is to know how fast the spindle is actually rotating. It gets this from the spindle index sensor, and not from what S word is in the Gcode.

So you can set the spindle speed manually. If the spindle is rotating too fast such that the Z axis can't move fast enough to cut the thread. Mach3 will halt giving you a warning message of this.

Cheers,

Peter.

279

Modbus / Re: Hitachi X200

« on: October 28, 2010, 08:16:08 PM »

Hi,

OK, I haven't done it yet. but this is how to go about it.

I'm using Appendix B of the manual Modbus Network Communications

First of all you need to set the OPE/485 switch S7  on the VFD to  the 485 position. THis tells the VFD that you are controlling it by Modbus


Once you have done that, you need to test that the com port and RS485 is working correctly. To do that, go into the "Test Modbus" page. You get there from the button on the top right hand corner of the Modbus config page.



Set up the port and press the Open port button. If that works, then you can try and read some data. I'd suggest you try and read the inverter status register, register 03

So, set up the data as shown in the picture. Then press read. hopefully, you will see some data in the list on the right and the status will show no error.




The slider bar, can be moved to the right to have the data continuously read.

If you get an error displayed you will need to sort that out before going further.

Let me know how you go.

Cheers,

Peter

280

General Mach Discussion / Re: G540 charge pump pin 16 is 2v instead of 5!

« on: October 26, 2010, 01:10:48 AM »

Hi,

Have you read the GeckoDrive Initial setup guide that talks about putting the parallel port into EPP mode so that the chargepump will work?

http://www.geckodrive.com/upload/G540InitialSetup.pdf


Give it a go and report back.

Cheers,

Peter.