I recently ran across a specification requiring a stand alone control board installed in a personal computer that was able to be custom programmed much like a PLC, but that did not rely on the PC's operating system. Basically the required board had its own processor running its own application program, but it only relied on the computer for its power supply and as a means of interfacing to a user. The specification required that if the computer completely locked up or shut down, the controller board would continue executing its control functions as long as it had power.

I'm familiar with PC based control, but that runs in the computer's processor. I'm also aware of some specialty boards for things like motion control that reside in a computer but run on their own. So far, I can't any components that allow completely custom programming but that reside as an autonomous entity within a personal computer. --Can anyone point me toward this animal?

 

Omron makes a board that does just this. It programs as a C200 controller, and meets all the criteria you describe. You can even reset the PC to reboot it without stopping the ladder program in the board. It uses various fieldbus solutions for I/O, or you can get a local (small) I/O board for it. It uses the PC bus for communication to the operator interface.

I do not have a part number handy, but I suspect a call to 1-800-55-OMRON, or a trip to their website (www.omron.com) would get you on the right track....

--Joe Jansen

 

I'm not sure but try this link http://www.modicon.com/PLCIO/atrium/body.htm

 

Omron have a PLC on a PCI card. Runs remote I/O. It is programmed with Omron Cx-Programmer software and powered by a separate 24 vdc power supply (usually batteries). If the PC operating system locks up or the PC is turned off, the PLC continues to run. Omron FINS Gateway software is used by SCADA packages or other software to access the data from the PLC.

 

You may want to check out: http://www.ctcusa.com/ctcnet/MLspec.asp

Best Regards,

Nick Pirog
CPU Automation
Phone: 978.692.5404
Fax: 978.692.8844
email: [email protected]

 

I believe that Siemens used to sell something like this, and quite likely AB did as well and possibly others. I don't know if these are still available. These devices were essentially a form of their standard PLC CPUs arranged on a plug in board. The I/O was all done via a network connection directly from the board.

With a reasonably good network connection between a PC and PLC, there is no need to put the PLC CPU inside the PC in order for them to share data. I
believe they were intended to address customer fears about the unrealiability of WIndows (the infamous blue screen of death) when used with with soft logic systems, while still offering close interaction between the PLC CPU and the PC. I was never really sure they were a good idea.

You might consider offering your customer a system involving a conventional PLC with an ethernet (or other) link to the PC. This is likelly to be even more reliable, and more likely to be more supportable over the long run.

--

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Michael Griffin
London, Ont. Canada
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Hi,

Schneider Electric has such a card operating exactly as you describe. It is part of the Premium range of PLCs and it is programmed as a PLC, providing high reliability and performances. As part of the Premium range this card is called Atrium or PCX

You can find all information on this product at :
http://www.schneiderautomation.com

Just hit the search button on the homepage and search for : Atrium Premium.
Just checkout the pdf document called "Premium Automation platform January 2003" (should be the first in the list of results) and get the information you need at page 20.

I hope it helps.
Regards
jm

 

Arnold,

You may also want to check out www.entertron.com for board level PLCs.

God Bless,

Stephen Luft
Entertron Industries
3857 Orangeport Rd.
Gasport, NY 14067
Tel: 716-772-7216
Fax: 716-772-2604
web: www.entertron.com

 

Siemens sells a PCI Slot-CPU in two flavors(412-416), it has Profibus and MPI on-board and can be equipped with an external Power Supply. I believe it is already capable of multi-processor (in other words you can place more than one in a PC) and it has an option, named T-kit to communicate through DP-Ram with it

Regards
Ronald

 

Some PLC manufacturers provide PLC-on-a-board.
For example Siemens proposes a S7-400 CPU to be installed in a PC. The product is named "WinAC slot PLC"