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Author Topic: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup  (Read 22536 times)

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Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #20 on: November 03, 2013, 02:26:08 AM »
John, you are absolutely correct.

Sorry for not updating the thread, we have been slowly chipping away at some of the issues. We wired the machine up as suggested, with the AMPENx in series with the opto-22, so MO will kill the motors etc. We also set up the off on error. We have purchased an oscilloscope, and have found a few interesting things;

 - We have traced the cause of the machine running away back to the F to V converters. When you start the machine for the first time (and the motors are stationary), they are outputting a signal of 10v. If the drives are then turned on, the motors run away.

 - Switching the drive power off and on will return the output voltage to 0v when the motor is stopped, and the machine is completely controllable until you switch both the cabinet and the computer off.

 - Alternatively, the F to V converters have some sort of shoddy switchable circut, which introduces 5v to various places on the board when activated (see photo linked below, the yellow and black wires going into the front of the boards). This is connected to a relay on the opto-22 board, and flicking this on and off a couple of times will set the voltage to 0v when the motor is stationary. You can then turn the drives on and again the machine is completely controllable until you switch both the cabinet and the computer off.
Photo (sorry for the poor quality and large size) http://img199.imageshack.us/img199/4765/gw06.jpg

 - Once the machine is controllable, the voltage out of the f to v converters seems to be pretty stable and consistant with relation to motor speed.

 - The encoders seem to be only recieving around 4v. They are using the standard galil 5v output, however there appear to be alot of things attached, and the 5v is being pulled down to around 4v. The F to V converters have their own individual precision 5v output, we are unsure if using this would be better or if it does not matter?

It appears that once we have this sorted out, the axies should be functional. Thank you everyone for your help so far.

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Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #21 on: November 03, 2013, 05:28:16 AM »
Hi I know that western digital do some neat pluggable frequency to velocity converters that might work better. On the Heidenhain system I have the encoder voltage has to be smack on or the control will alarm out..not sure with the galil card but keeping to a true 5v is always best.

John.
Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #22 on: November 05, 2013, 02:41:57 AM »
Thanks for the reply John,

Who makes the converters? Is it western digital the hardrive manufacturer?

Jack

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Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #23 on: November 05, 2013, 03:47:59 AM »
Hi Jack sorry my typo! It"s actually us digital ..just been on there sight and I can't find the converters  now but I'm sure if you contacted them they would find the product for you.

John.

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Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #24 on: November 05, 2013, 04:06:29 AM »
Jack,

I found it under discontinued products..

It's the ETACH2 www.usdigital.com

I'm sure another company will make something similar...

John
Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #25 on: November 05, 2013, 04:09:45 AM »
No worries John!

I found the converter your thinking of by us digital its call the etach2 (http://www.usdigital.com/products/interfaces/encoder/converters/ETACH2). It looks ideal though they say the part is obsolete and no longer available. At this stage it looks like I have 2 options, Either attempt to run the machine as is or possible look to retrofitting some new drives in? Gecko 320x or Rutex or something similar? Whats your thoughts?

Thanks
Jack

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Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #26 on: November 05, 2013, 05:20:14 AM »
I personally would keep the original drives and try and find a converter  as your  drives are industrial quality much better than Rutex or Geko types...the only other option I would look at would be fitting ac drives and motors such as Yaskawa or Mitsubishi but this would be an  expensive option as you may also have to start with new motor plates and all the cables for the new motors would have to be bought and fitted on the machine.

John
Re: Kitamura T-12 with Galil DMC-1840 and Contec I/O Setup
« Reply #27 on: May 12, 2015, 01:11:19 AM »
Wow doesn't time fly......

To update the situation we battled with the drives as time allowed and while we technically got the machine to function we have decided to install new servo drives.

The machine could be made to function and was reasonably well behaved however would arbitrarily run away which we are not interested in at all.

We have selected AMC servo drives to run the machine and have purchased one B30A40ACG to use as a proof of concept on all the axis and once we are sure it will work for us we will order three more.

The main question at this stage is what VDC does the drive put out? Is it just a function of the voltage input on the AC side of the power supply? How is the bus voltage set as it is unclear on the datasheet supplied by AMC. The simplest option for us is to run it on 200VAC as we have a transformer for this voltage here (line voltage in New Zealand is 230v/440v 50hz).
http://www.a-m-c.com/download/datasheet/b30a40ac.pdf

Also I have no idea what the 'G' modification represents in the part number which I hope won't hinder us....

Hopefully this time it should all be much simpler as the hardware is all modern etc (less hours with the oscilloscope hopefully :) )

Looking forward to some info,

Thanks
Jack W