Choosing the Right Touchscreen Display Technology for Your Control/Automation Process
- Created: Monday, 01 March 2010
Open Operating Platform HMIs
If you want more software options or simply need more in your HMI than the proprietary configuration software can deliver, then an open HMI might be a logical choice to meet that need. The open HMI has a touchscreen display like the standard HMI control panel, but it has an open-platform operating system like Windows CE or Windows XP that allows you the ability to utilize other Windows-based applications.
So let’s say you want to utilize a more substantial configuration software. The Windows operating system will allow you to do that. And of course, with the Windows operating system, you have access to a whole new universe of software applications and features like Web browsing. And with the browsing capability, you can network your open HMI over the Internet, take advantage of files in the HTML format, and of course, take advantage of any other online capabilities.
Your choice of CE or XP-embedded will depend upon two factors. The first is simply the fact that Windows CE is a much shaved-down version of XP and is therefore less expansive. But it also requires much less hardware capacity (memory, processor) to operate correctly. The XP version gives you the expanded options of the full operating system, but it is more expensive and it does require more substantial hardware.
It is important to remember, though, that in either case, the open HMI is not a full-fledged PC or industrial computer. It’s an HMI with an expanded capability. Think of it as the midway point between an HMI and full-fledged industrial computer or panel PC.
Panel PCs or Industrial Touchscreen Computers
Panel PCs are an interactive touch-screen display technology that offer the efficiency, power, and connectivity to create an automation process based upon your primary design objectives, rather than being forced to sidestep around the limitations and design roadblocks imposed by conventional HMIs/panel PCs.
Panel PCs are full-fledged industrial computers with touchscreen displays, fast processors, lots of memory and drive space, the Windows XP Pro Operating System, and beefed up connectivity with several USB and Ethernet and serial ports — all encased within a durable enclosure that panel-mounts into a console or instrument panel. They come in both light industrial and heavy industrial product lines; the heavy industrial with a more rugged design, anti-shock drives, and much more substantial enclosures.
Panel PCs have all the capabilities of any full-strength PC and can literally be placed at any level of your automation control process. From the corporate home office to the plant floor of your manufacturing site, the panel PC gives you all the power and options you’ll need.
And like any HMI, they can be networked over and into the entire automation process to communicate with other panel PCS, other HMIs, or even the corporate server. You can treat it like a standard PC with a keyboard, or utilize its touchscreen capability. Yet, like all HMIs, there’s no tower — all hardware is packed tightly behind the display.
These units offer much greater latitude in the creation and facilitation of the automation and control process. Although substantially more expensive, they should not be overlooked for their capability provides you with many options not otherwise available.
Control Operator Interface Terminals
This technology is a combination of the touchscreen interface with the controller. An “all-in-one” deal, the units have a touchscreen display (sometimes with adjacent hardware keys), and on the back of the unit are plug-in controller modules with I/O (input/output) connector clips.
Some “last, but not least” points to consider: HMIs, open HMIs, and panel PCs all have various levels of hardware options including add-ons like barcode scanners, CD/DVD players, microphones, and keyboard and mouse (if you don’t want to utilize the touchscreen). If you are going to need such add-ons, don’t assume that all HMIs are created equal. Check with the manufacturer first.