Hardware / IO Simulation

I'm looking to buy / build a simulation tool that I can use across multiple PLC makes - mainly Siemens, Rockwell, Mitsubishi with occassional Unitronics and others (Panasonic, Omron)


What I'm thinking is to use something like a Red Lion to create an IO simulation that I can then use to test the code, train the operators, etc etc without using the real world IO.


In a previous life I used PICs, which was great, but expensive and this time around I'm paying for it myself.


Do you have any recomendations and what should I avoid?


Thanks

Andrew Hardy said:

I'm looking to buy / build a simulation tool that I can use across multiple PLC makes - mainly Siemens, Rockwell, Mitsubishi with occassional Unitronics and others (Panasonic, Omron)


What I'm thinking is to use something like a Red Lion to create an IO simulation that I can then use to test the code, train the operators, etc etc without using the real world IO.


In a previous life I used PICs, which was great, but expensive and this time around I'm paying for it myself.


Do you have any recomendations and what should I avoid?


Thanks

Click to expand...

What are you looking to simulate? The PLC code or the process? Will the real PLC still be there?

When developing new PLC functionality for projects I routinely program extra parts of PLC code that simulate input behaviour based on the PLC outputs, instead of being mapped to real hardware inputs. Usually with some extra inputs that I can switch on/off at will. By the time the hardware for the machine is built and put together, it gets shipped to the customer almost right away. Only for new stuff that we haven't done before I usually try to negotiate some extra time in the workshop for more real life testing and improving before shipping.



Some projects need more than just a relatively small number of inputs/outputs responding somewhat coherently for testing. On a few occasions I have built a simulator (in another PLC) for the newly programmed machine software to talk to, making it seem as if it is acting on a 50m long real world machine while in reality it is just two PLC's and a whole bunch of wires sitting on my desk. There is one simulator that I built several years ago for a machine type that we sell many variations of. At times that simulator is in use almost full time, from one project to another.

I too used PICs but as you say is expensive, What I do now even on simulators is map the real I/O to internal bits in separate blocks so for example
A X0 Out M0
......

A M20 = Y20 etc.
Make the symbol (tag name) similar in both the actual I/O and the mapped bit i.e. X0 = End_Travel_PX M0 = End_Travel_PX_M (used the "M" to denote the map bit
But do not call the blocks, either put an always open contact in the call or just not call it.
Then write your code using the mapped bits, when finished testing, call the blocks for the I/O mapping.
I also create blocks for the simulation so for example if you have valves with limits then write code using say the mapped output memory to drive a timer (to simulate actual movement time) to set or = the Open px mapped bit and so on. you can increment/dec analog values etc. then delete the blocks after testing, it is sometimes easier the write the code in the PLC rather than these simulators supplied. It's just like you did in PICS but without the real I/O.
I also have a spare HMI that I can use to simulate buttons and display a graphic of the process if the actual plant does not have one and only uses buttons/switches.