Now you've done it. Once again the great PC vs. PLC debate has been started.
Seriously, I believe that any control
done properly can be a good control. Likewise, any control done poorly can be a nightmare.
It does seem that because PC's can be more open than PLC's that there is much more to take into consideration to do it properly. However, there are some things you cannot do without a PC.
Maybe the best solution is a hybrid where a PLC does the control of the harware I/O and a PC with an OPC server does data collection, Bizware stuff, alarm e-mails, database integration etc.
Entivity is now owned by Phoenix Contact. Their main product brand names are Steeplechase and Think & Do. Both are mainly flow chart based programs. You can start checking things out here:
http://www.phoenixcon.com/software/
The PC Worx product is an IEC61131 type software made in Germany and is not from the Entivity line.
With an open mind you may find things you like about it and I'm sure you will find things you don't like about it just like you will with any system. If one system fit for everything then there would only be one system.
You may also find that if it is a standard machine already designed with one piece of software, the cost from the OEM to change it could be astronomical. Besides the cost to do the actual conversion, they would then be required to support multiple platforms in the field, have multiple spare parts for service, multiple manuals, ... you can see it can baloon very quickly.
<disclaimer - I work for a Phoenix Contact Distributor>
