By Jeremy Pollard, CET
There's a free HMI project called PVBrowser. Who among you has tried it?
Mainstream vendors want and need your runtime business, development system be damned. It's nodes and tag count that matter. In fact, a customer of mine, whom I'm trying to show that thin client is the way to go, compared a fixed HMI cost against my proposal. They still are listening to me.
HMI and SCADA are blurred for sure, and vendors exploit that fuzziness. They want you, the user and the machine OEM, to be captive audiences. That's what keeps them going. OPC connects the world, but there is no common graphics standard and no common interface protocols. File formats are so totally different that once you are in, you are in with both feet.
The problem I have with the big guns isn't their technology; it's their tag-based licensing. More tag, more money. The resulting product isn't different; it's just a way to get more dough for the development and support efforts. That's cool. We only have thousands of users, not millions. I get that.
With a Visual Basic or VB.NET platform, that wouldn't happen. With a true Internet-based platform, that wouldn't happen. That brings me to Inductive Automation's Ignition server. It's a free OPC server, albeit only for Rockwell and Schneider (Modbus), with free runtime clients, minimal development costs and unlimited tags. 'Tis true. A Visual Basic solution (free stuff) with an integrated environment.
Why can't we have a common communication platform? Oh wait, we do—OPC. Why can't we have a common graphic platform? Oh, we do—GIF or JPG. Database—SQL. Conversion platform—XML. Interface protocol—HTTP (Web browser).
So what exactly is a real HMI/SCADA platform? It's Legacy. This is why Ignition is so cool.
Totally based on the open technologies of SQL, XML, HTTP and others, Ignition will allow a user to migrate all applications to this platform.
It isn't a standard. It isn't free. But it supports most common technologies. I'm unsure if the industry can adopt a common graphics format, but we certainly should, and vendors should supply their graphic object files with all the properties required to drop into our selected graphic profiles and programs using data points and nothing more.
Ignition is the first platform that can take us there. It isn't an HMI. It still needs a dev server, so for single machine control, it wouldn't be effective. But for a system where more than a few nodes were required, it could be worth it.
My excitement with this product is because it can redefine the paradigm. The up-and-coming control geeks might or might not be VB.NET-versed, but they sure are Web-versed and well aware of the inherent common technology platforms that commercial software brings to the table.
Beware these new geeks. They don't have pocket protectors, but they do have iPhones. They are as tech savvy as we used to be, but a lot of graphics-based companies are living in a Jethro-Tull-based past. In a recent survey, most respondents would go to their technology suppliers for HMI/SCADA products. They do not go outside the box.
The available technologies are homegrown and otherwise abundant. You really must investigate since it will save you money, time and grey hair.
I first chose VB many years ago for a project with 40 nodes, five applications, three concurrent users and a tag count of more than 1,000. This project with a normal vendor was going to cost more than $130K, excluding hardware or development costs. We accomplished the project with a server and PCs with development costs of less than $30K. My customer went, "What??"
Companies like Inductive Automation can change the landscape. Look over the HMI/SCADA terrain and determine if you should change. Legacy is out there. "I think I just will go with what my automation supplier tells me" won't cut it. Innovate, experiment and be successful. Don't see your future in the rearview mirror.