There are some key differences between MTConnect and OPC UA where many folks get confused that I am going to clarify. I have had this conversation countless times and had one this past Friday and thought it was time for a blog post on it. Let me make sure everyone understands that MTConnect and OPC are working together and this is an educational blog to clarify the key differences between the two and not a battle cry.
Here's the net/net or punch line.
THE single MOST important difference MTConnect and OPC UA is HOW you get the data which came about directly because of HOW the MTConnect Institute organized the MTConnect Technical Advisory Group (MTCTAG) to create the COMMON dictionary of terms. Don't worry, I will expand on this :-)
First some background. In general, OPC is used for process manufacturing and MTConnect is used for discrete manufacturing. Process manufacturing is where a big bale of coffee beans comes in the left end of the plant and small k-cups come out the right end of the plant. Discrete manufacturing is where larger pieces of metal go in the left end of the plant and smaller pieces come out the right end of the plant and those smaller pieces are called finished parts such as landing gear for a jet.
The applications are what you "plug" into an MTConnect machine tool or sensor.
This is where folks in the OPC world can purposely obfuscate what is really going on or they simply do not understand what is going on with MTConnect and muddy the waters. Someone from the OPC side of the house can say, "well, we provide electricity (machine tool data) so why do you care HOW you get it as long as you get it?" It is the classic false choice version of black and white logic.
The reason manufacturers CARE is because they want MORE than just the wiring. They do not want to figure out what type of plug, voltage, amperage and AC or DC current (machine tool or sensor data ) they need to use, they simply want to have a common standard they can easily plug into to speak to their many electrical appliances (applications).
Can I use OPC for the world of discrete manufacturing? It begs the question, can I create my own outlets to use for my own appliances that are wired my unique way? Sure, but WHY when MTConnect is elegant in its simplicity and is the de facto standard for discreet manufacturing interconnectivity?
Let me say it again, there is NO Machine Tool Working Group in OPC that has agreed upon a COMMON dictionary.
The goal of MTConnectOpcUa is to have a companion spec to ensure interoperability, but let's not forget MTConnect's secret sauce - the machine tool industry companies and others who came together to create an open source, free to use and free to deploy interconnectivity standard WITH a COMMON dictionary.
I wanted to make sure everyone understands the most important differences between the two connectivity standards, but please do not take this the wrong way as I am a big fan of OPC and the OPC Foundation, as well as Tom Burke, but again, there are key differences.
Below is information on MTConnectOpcUa - the companion specification for both organizations.
On September 16th, 2010 the MTConnect Institute and the OPC Foundation announced MTConnectOpcUA:
"Chicago, Il. … Today, September 16, 2010, at the International Manufacturing Technology Show, the OPC Foundation and the MTConnect® Institute are announcing a joint Memorandum of Understanding. OPC and MTConnect will cooperate in developing standards called MTConnectOpcUa. MTConnectOpcUa is a set of companion specifications to ensure interoperability and consistency between MTConnect specifications and OPC specifications, as well as the manufacturing technology equipment, devices, software or other products that implement those standards.
Tom Burke, President and Chairman of the Board for the OPC Foundation, stated, “MTConnect & OPC collaborating will provide the necessary infrastructure to revolutionize interoperability for the complete spectrum of manufacturing technology, by leveraging the standards of both organizations, evolving the technology that has already been well accepted and adopted by the suppliers.” Dave Edstrom, President and Chairman of the Board for the MTConnect Institute has stated, “This is not just a win for MTConnect and OPC, this is a huge step forward for manufacturing interoperability around the globe.”