AB SoftLogix

[G_DeMark 2]

Does anyone have any experience using AB SoftLogix?  What are the advantages / disadvantages?  Obviously you do not get the benefit of a robust PLC processor when you are running on a PC.  However, if you do not have a mission critical operation and you would still like to utilize the ladder logic environment it is an interesting option.  Does the SofLogix offer any advantages in regard to integration with other Windows programs (like a database or even excel) given that is already running on a PC.  Thanks

[Joe E. 259]

At a previous employer, we had 5 production lines that each had its own SoftLogix control running on a Windows XP (I think? may have been Win 2000) PC.  For the most part, they were very reliable, except for line 2 whose PC would randomly reboot itself while the system was running.  The system log never showed anything that was useful and it never showed a BSOD that we could catch. 

That line ended up being used mostly for prototyping and short production runs so it wasn't as bad as it could have been but each reboot cost a fair amount of scrap and about 30-45 minutes to restart the line (10 dual-cavity brake pad forming presses).  I was just getting started with automation and controls at that job and I was only there about 2 years as a maintenance tech so I can't really describe the system architecture to you except I'm pretty sure it had DeviceNet boards in the PC to interface with the drives (a servo drive per cell plus a raw material delivery shuttle and a finished product unload shuttle).

Each system did have a PC based HMI program running on the SoftLogix PC.  I have no idea what software they used or if it was easier to implement with it being on the same PC.

In general, I prefer to use a dedicated PLC instead of SoftLogix.  Where I am now we have several systems that use a data collection PC to read stuff off of the PLC via Ethernet.  We had almost no trouble at all getting them to work, even with one of the data collection PCs being remote from the line.

Edited 6 Apr 2017 by Joe E.

[PLCMentor.com 60]

In most instances I would just say no.  There are some PC hardware setups that are fairly similar to the robustness of a PLC; however, when you compare costs I suspect the PLC will be cheaper.  The windows operating system does not really have the reputation for solid 24/7 operation unless maybe you go to one of their server packages.  Also ladder is not chosen because of its mission critical capabilities but due to its (supposed) familiarity for maintenance personnel.  I would ask yourself this.  Will it matter if I have to reboot my control system periodically?  If not then PC control may work for you.  I dont have any installations where this would be acceptable.

Edited 6 Apr 2017 by PLCMentor.com

[G_DeMark 2]

So I am very clear that the "hard" PLC is the more robust solution.  Unfortunately, my current employer is in love with LabView.  I am trying to get them to consider PLC.  from what I can tell LabView does have some advantages.  For example, LabView's ability  to exchange data with a database like SQL server is very nice.  When I propose a PLC there is the need to purchase an OPC server (like Kepware) which adds some cost and complexity.  So, I am wondering if the softlogix can more easily integrate with windows applications given that it is also running on windows.  This would only apply to smaller applications that do not need 24/7 uptime.  Thanks

[PLCMentor.com 60]

Well you hit upon another of my dislikes - Labview.  But that's more of a personal preference.  I suspect you will still need some sort of OPC server to talk with softlogix also even with them both on the same PC.  This is just conjecture, but softlogix attempts to look like PLC hardware and uses standard methods of communication, ie some sort of OPC server.

[G_DeMark 2]

That is what I figured.  I am trying to keep an open mind, but I am really disliking the LabView data flow model.

With all of this said, I wonder why someone would use Softlogix.  Perhaps just to save some money on the processor.

  Thanks

Edited 6 Apr 2017 by G_DeMark

[Gerry 13]

Soft plc's were a fad about 20years ago that never gained popular use in industry. They can be useful for training purposes and experimenting, but reliance on Windows and typical PC hardware made them unsuitable for production environments.

The only plus they offered was memory capacity.

For most systems, the major cost is in I/O modules and their necessary accessories, making the processor cost relatively minor. And Softlogix is not free.

And yes, you definitely need all the same software packages to communicate as would be required with a PLC.