Looking for a Non-Windows Based DCS System

Dear All

Thanks so much in advance for all your contributions in the various threads. I have been benefiting a lot through your insights into various topics on Plant Control and Automation.

We are a Specialty Chemical company and currently have 20 plants under windows based DCS systems. Our vendor continuously approaches us to upgrade the DCS system(and has been charging for upgrade of some plants at a time) claiming that Microsoft has stopped support for the operating system and instead of charging the major amount for the Microsoft license fees and nominal fees for his systems, charges us almost 50% of original system cost claiming the entire system needs to be upraded while also charging for replacement of cards that are not compatible with latest version of their software. Apart from this they are periodically stopping manufacture of original hardware with the old system claiming it is a corporate decision.

This has created an ongoing nuisance for our organisation and hence I started looking at Unix based DCS systems and/or any other options that do not have this ongoing upgrade discussion especially with Microsoft systems.

Thanks much for your assistance and insights in advance
With Warm Regards