[SuperBob]

Anyone have any thoughts on how best to control 40 to 60 air cylinders
from a p.c.? best cost is initial concern......

Thanks!

[Al_The_Man]

There is very limited information there, would not a PLC be a better choice, and do you need operator interface? Or stand alone run?
If a PC is a must, there are PCI I/O cards that will interface directly to OPTO style SSR module units.
You will need suitable front end controlling software for this.
If you are open to used or NOS, ebay is a mine of resources for this equipment.
Al.

[SuperBob]

I do need an operator interface, probably vb based, as it will need to access some database stuff too.

I have looked at Galil, but I think that could be overkill... and I would have to buy like 3 of there units to get that much output.

Any thoughts on other makes or types of stuff that will inteface with a p.c.?

Thanks!

[SuperBob]

Basically I need to read an rfid chip, pull specs from a database, and use those spec's to fire the correct combination of 40-60 cylinders.... maybe also sensors to make sure they have fired.... ugh. And operator interface to aid in the control i.e. enter password make changes etc.....

[Al_The_Man]

Unless you want motion control, Galil would be a sheer waste of money.
Contec supply these PC I/O interfaces http://www.contec.com/productsdir1.html
If you want to develop your own VB based system, otherwise it would mean using s/w such as LabView etc with them.
If you want to go the cheaper route and design your own, you could do this with a PicMicro system.
And if you do not need the PC glitzy interface, maybe a small keyboard and 2 ~ 4 line display?
If you need cylinder position confirmation, make sure you get the cylinders with magnetic ring on the piston for external detection.
Al.

[SuperBob]

Thanks Al!

[Al_The_Man]

As an afterthought, to reduce the hardware from the PC and the fact you may need over 120 I/O you could use a network link such as the OPTO Modbus method http://www.opto22.com/site/pr_detail...0081008,,,2,3&
The removes all hardware from the PC and makes all external.
I think they even have development s/w.
Al.

[bharbour]

If you are really locked into a PC, there is a company called Adlink that makes parallel I/O boards for PC's. The ones I used were pretty high speed, but they also make slow, high channel count boards. Their software libraries work fine with MS tools. I have gotten them from these people: http://www.circuitspecialists.com/level.itml/icOid/101 but others probably carry them as well. I don't have any connection with these people, just a local shop that I get stuff at from time to time.

To be honest, this seems like a PLC or a custom solution would be the best choice. You are going to need drivers for all of those valves in addition to the raw I/O. It is not complicated, but there are a lot of them. A PLC has boards that will drive valves directly.

How fast does this need to be? How is it timed?

Good Luck,
BobH

[SuperBob]

the i/o speed does not need to be fast at all.....

Timing will be controlled by the computer, this is for a setup type operation
i.e. very simple procedure, look up proper cylinder combination, fire cylinders,
wait a couple seconds for all to extend, release "tie -down clamp", done.

Thanks for the lead!

I think I have found some mead isonic series valves a set of 8 on a carrier base for $95, that helps.

I will check out your parallel port lead stuff too!

Thanks!

[Tig]

Hi SuperBob,

If you don't mind me prying, are you building a stretch former for metal?