building xy table and servo tapping

[jimc]

I have been collecting stuff from ebay, and am now deciding on how to proceed. I have all the ball screws and servos with encoders, a Galil DMC 2040 4 axis controller with an ICM 2900 pinout or whatever you call it, servo amps, power supply, a 4 foot air slide, but am lacking a few support rails. I also have a spare Fanuc 90-30 PLC and the Versa Pro software to program it.

I muddled through the PLC programming to get another tapping machine (with a 90-30) running, so am familiar with ladder logic.

I have been reading the Galil users manual, and it's even more confusing than the Fanuc manual was. But I need real control on this x-y table - hence the Galil.

This machine, and x-y table, I hope to expand to include screw insertion under another head - hence the 4 foot long air slide.

The more I think about it, the more it seems to make sense to use BOTH the PLC and the Galil, since the screw insertion operation is likely to be using a lot of sensors and a lot of inputs and outputs.

Does anyone have any thoughts on this? And has anyone combined the two in the past with good results?

I made adaptors for two of the ball screws last week, and have mounted the servos. One is hooked to the Galil and I can make it move in sequential moves now. By sheer cooincidence, one encoder count equals .001" of linear travel. I still don't know how to actually write a whole program and get it into the controller, then push a button and have the thing do what it's supposed to. But I will hopefully get to that part within a couple weeks or so.

But those kinds of questions are for later.

Thanks.
Cheers,
jimc

[Al_The_Man]

This is an ethernet card is it not?
How were you thinking of communicating with the PLC?
And what type HMI did you plan on using for the Galil?
An I/O expansion module would be an option.
Al.

[jimc]

Al,

The Galil is a stand alone 4 axix controller. I'm using my regular computer to send it info - but once I have the motion downloaded to the controller, I'll just push a button to start the tapping cycle. I start the other machine with two opto switches that have to be engaged simultaneously.

I checked the Galil website for an extended IO, but they show it as obsolete and do not list it for sale. The do mention that both opto-22 and Greyhill made one that will work. I will call Opto-22 on Monday to see if they still have them and how much they are.

One thing about the Galil that scares me is having to figure out all the "intuitive" control programming, as opposed to using ladder logic, whcih is nothing but a bunch of pictures.

Anyhow, once the machine is built and running, hopefully I won't need much interface except when changing out broken taps, unless I change the part designs or have to add more safety programming.

I couldn't believe how many sensors and switches I wound up with on the other machine by the time I was done. What a mess of wires!

I really don't know what the best plan is. Oh, I use a windows computer to program the PLC too.

Cheers,
jimc

[Al_The_Man]

If you are thinking of persuing the expanded I/O, I would contact Galil, I recently got a I/O for one of the older DMC1000.
If you are looking at stand alone in the future, the 1500 is a viable option, in fact there are a few that come up on ebay with expanded I/O.
The thing I like about the 1000/1500 line, is you do not need the expensive break out, it can be done with 3rd party IDC ribbon to terminal connectors.
I have implemented some 1500's using the Maple Systems Operator 2 line keypad interface units via the RS232 hook up.
The Galil is very easy once you get the hang of it with the two letter commands.
The main issue with using a PLC is that you only have the the 16 I/O to communicate everything between PLC & Galil, unless you intend using a port.
Al.

[jimc]

Well, you are probably right that I'll need one in any event. In the meantime, I'll mess with the Galil some more and see if I can figure out all the if and else stuff, and how to turn a bit from low to high. I also want to gear one of the motors to another. I suppose for tapping, I should have the tapping spindle as the master and the feed motor as the slave.

Are you familiar with the Galil "Smart terminal" that is the free download way to program their controllers?

Thanks, Al.

Cheers,
Jimc

[Al_The_Man]

Yes I have used SmartTerminal but I program mainly with the 1000/1500 so I use DOS extensively, so I use the DMCTerm which is the DOS equivalent.
You can run the card a command at a time or interogate, or use the editor to write a program to download to the card and run it.
You can run a separate 'Thread' as say a PLC style program for I/O.
I have found the Galil a little restrictive for PLC use as it is a bit cumbersome to write Bit-wise Boolean logic that you may be used to on a separate PLC.
BTW one of the reasons I still use the 1000 apart from the direct ribbon output to Opto cards, is I still use the OPINT DOS s/w that Galil dropped sometime ago due to the popularity with Windows and the demise of the ISA buss.
But it is too bad, as if it is an amazing way to write HMI screens and run programs, had ISA/DOS stayed popular I think the development would have carried it even further.
For the majority of applications, not only do you not really need Win, but it can be an hindrance IMO.
Al.

[jimc]

I just realized I put this post in the wrong catagory. There are so many catagories, when I finally came across servo drives, I jumped the gun, not noticing it was in the Rutex section.

My apologies to all.

jim