Ok so I know that SIMATIC S7-PLCSIM is out there to act as an emulator if you don't have a physical PLC to write and test programs with... but it is not free  and don't think my company has it nor do I think I can get it approved as an expense.

Does anyone know of a good freeware version of something like this?

If not... what are good pay-for alternatives if any?

You can write your own simulation in the PLC by writing the inputs according to the outputs

Francis
www.controldraw.co.uk
www.s88control.blogspot.com

With all due respect... I don't think you read the post.

What if you don't have a physical PLC?

Point taken but it is hard to imagine what you can do without the PLC. As for Freeware in the industrial world, mostly it's worth what you paid for it.

Francis
www.controldraw.co.uk
www.s88control.blogspot.com

"Point taken but it is hard to imagine what you can do without the PLC."

You throw you weight around in this and other threads as someone well-seasoned in industrial environments specifically related to automation and then say this.  You can to plenty with a PLC Simulator... you can write programs with bits representing IO... you can write an HMI for it to test it... you can have a program virtually ready before any hardware shows up. Wow... think out of-of-the box a bit eh?

We are at cross purposes methinks
You can get a small PLC for not much money, perhaps even a bottom end S7.
You can get PLC programming software for a little money (even free for Design time only)
But you want it for Simatic S7 and for nothing.



 

Francis
www.controldraw.co.uk
www.s88control.blogspot.com

"But you want it for Simatic S7 and for nothing."

Yah this is an exercise.  Why should I pay.  And... oh wait a minute and I forgot all PLCs process their programs, and have block elements that are all standardized across brands.  So I can use any PLC right?  [Sarcasm]

Good luck, guys. I think I put my bet on the OP.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

"Yah this is an exercise.  Why should I pay"
Talk nicely to your local Siemens rep, they might understand.

 

Francis
www.controldraw.co.uk
www.s88control.blogspot.com

Bill Gates once said something to the effect... the person with their software on the most machines wins (hence not tying the software to the machine and a relatively lax enforcement with respect to violators ... v. apple "you have to do things our way so we can keep making you pay.)  Though being expected to pay for product is common sense... in this case it is a matter of... well... the industrial development field rapes people with propriety.  Wouldn't it be better if manufacturers allowed people to learn how to make their hardware work... at little to no cost... then more and more people get comfortable with it... they will recommend their over-priced hardware time and time again because they know how it works... even though you can buy a network card for beans for a PC system... frankly... a whole PC for the price of some CPUs out there alone... and make their money that way?

Anyway... I am not participating in this particular thread until someone tries to help more thoroughly address my original question... the rest of you can debate here, off-topic as long as you want... I am not here to have a philosophical/business-model debate... I posed a question and so far I have only a partial answer.

So I can use any PLC right?  [Sarcasm]
Your Sarcasm is misplaced (or rude).
Yes, you can use any PLC so long as it generates the signals your PC is looking for via an OPC link for example. If all your PC has to do when it is not talking to the resto of the world is represent daa coming from the PLC you could simple get any PLC (or indeed Emulator ) and then manually set bits/values to see the effect in your HMI.
Changing the OPC to address a different (the real)PLC should be easy.

Francis
www.controldraw.co.uk
www.s88control.blogspot.com

I meant it when I said I am not going to continue this until this gets back on-topic.  This is my FINAL post to this thread until it does get back on topic.  Perhaps you should start a new thread "PLC processing/syntax is standardized across manufacturers... true/false?"