PC plc´s

[Siemon]

We have been using Siemens Softplc for about 10 years,just S7 software running on pc processor and it is ok but just that. Now we use softplc in a XP operative with no problem(big problems with the old version) with the software but it needs a PCI slot
for the Profibus card.Hardware standard in Pc is changing fast ,so beware.I think the Siemens SlotPlc is a better choice.It is a complete
S7-300 Cpu to use in a Pc.But the traditional Plc rack is King in the long run ,we have Siemens S5 Plc´s running for 20 years with no problem.

 

[Tom Jenkins]

What is driving the decision? If it is cost, this is probably a red herring. The hardware is usually the least expensive part of an automation system. How much will down time cost? There is little doubt that a PLC will be AT LEAST as reliable as an industrial PC. Is it so IT can access the system - this can be done with PLCs as well.

What is the payback on the PC based system? How long will it take to redo all of your progrqamming on a new platform?

Sounds like a mistake to me.

 

[lbg_dk]

What is driving the decision? If it is cost, this is probably a red herring. The hardware is usually the least expensive part of an automation system. How much will down time cost? There is little doubt that a PLC will be AT LEAST as reliable as an industrial PC. Is it so IT can access the system - this can be done with PLCs as well.

What is the payback on the PC based system? How long will it take to redo all of your progrqamming on a new platform?

Sounds like a mistake to me.

The program must rewritten whatever PLC chosen. Much is written in IL. It was written by a former staff member. Me and my partner are having difficult to understand the IL code and can not get support !

And there are maybe 35% off the core logic there must be changed to the next machine version.

Each Controler will get it own adsl conection with a vpn firewall.

And well yes cost is a factor. The numbers is in 100 to maybe 300 a year.

"How much will down time cost?" I am not sure i will try to check.


Thank you all for you inputs it is realy nice

 

[SteinCollector]

lbg_dk said

The program must rewritten whatever PLC chosen. Much is written in IL. It was written by a former staff member. Me and my partner are having difficult to understand the IL code and can not get support

Since TwinCat supports the CodeSys IEC 61131 software standard, there is a chance that you could copy and paste the IL code from your current PLC software into the new software, run a compile, and see what happens. You may not have to re-engineer as much as you think. One of the advantages of eventually switching over to Codesys-based IEC 61131 software is the transferability between 64 different PLC vendors (Beckhoff, Elau, Bosch Rexroth, Moeller, Wago to name a few). If you end up hating the Beckhoff solution, you can try a different vendor w/o as many headaches w/ re-engineering.

Codesys is definitely a different creature than Mitsu programming, though. Be warned!!

I work for Bosch Rexroth and we have sold quite a few PC-based systems in the states and we have seen very few problems with them.

Good luck!

 

[Peter Nachtwey]

And there are maybe 35% off the core logic there must be changed to the next machine version.

Any code should be redone using a higher level language if possible like ST. This is the first time I have actually heard of anybody using IL. The fact that whole project was done in IL amazes me.

 

[SteinCollector]

Any code should be redone using a higher level language if possible like ST. This is the first time I have actually heard of anybody using IL. The fact that whole project was done in IL amazes me.

According to my colleagues in Germany programming in IL is actually quite common over in the Old World, supposedly it is believed that this code executes faster.

Personally, I would use IL for the transfer and re-engineering until the program is compilable. Codesys software allows an IL program to be converted into ladder or Function Block Diagram.

 

[LadderLogic]

I would be very much surprised if Mitsubishi IL bears even slightest resemblance to IEC 61131 IL... I'd give it 0.5% chance.