These shifting definitions of IPCs can make it harder for users to find the right computer for their application, but it also gives them far more choices and potentially useful solutions and savings then in the past. “Industrial PCs are an equal or better replacement for PLC in a lot of industrial applications,” adds Falke. “Users sometimes prefer the security of PLCs due to their proprietary software, which can’t easily be corrupted by viruses or other PC software. Phoenix Contact addresses those applications with its new Steeplechase VLC-programmed, embedded controllers, such as the S-MAX VLC, that offer the security of a PLC with the speed and connection options of a PC.”
Nipun Mathur, National Instruments’ (NI) DAQ product manager, adds that, “Ten years ago, industrial PCs just displayed control and I/O tasks on an HMI, but then they began getting ruggedized and enclosed in 19-in. rack for use on the plant-floor, which moved them closer to PLCs. Meanwhile, PLCs became more open, and added faster processors, advanced analytics, and control algorithms, which pushed them toward the process automation controllers (PACs) and IPCs,” says “Now, the hardened laptop or blackbox on a 19-in. rack concept has been broken out into all new areas. So, while the PLC automated tasks for more efficiency, more advanced control and plant monitoring requires a platform that runs both high-speed control and real-time analytics, and that’s what a PC can do well.”
For example, ABCO Automation reports it recently used NI’s PC-based PACs to develop a 14-station assembly and verification conveyor line and a 10-station final testing line for an automotive sensor manufacturer. To help the line produce its mandated one part every six seconds, NI’s LabVIEW Data Socket was integrated with Rockwell Automation’s Allen-Bradley RSLinx OPC server, which allowed NI’s PAC hardware to work better with traditional PLCs, and provide seamless control and data monitoring. NI adds its new ability to speak to A-B’s hardware saved it valuable programming and integration time on ABCO’s job.
In addition to evolving in the direction of PLCs and carrying our their functions, IPCs also can serve independently as headless network servers, collect data from machines, and pass it up to enterprise levels, according to Aponte. “We have one user that mounted our Microbox T computer in a confined space for automatic, material-handling control because he needed an IPC to control drives and motors, but still be close enough to his application’s actuators. “This was a job that PLCs did in the past because they were the real-time devices and PC were not, but dual-core Intel processors are allowing much more PLC-like control by industrial PCs.”
Probably the most significant recent change in industrial PC technology is the increasing use of Flash memory and cards. Because these components have no moving parts, they’re much less vulnerable to many of the environmental stresses that can plague fast-spinning hard drives or their related cooling fans. Logically, less vulnerability inside a device means less need for protection outside a device. “The users’ preference is naturally to get rid of hard drives, fans, and any other moving media,” says Aponte.
|FIGURE 1: IPC AIDS SHANGHAI WASTEWATER|
Beckhoff Automation's CX1000 embedded PC helps manage bus couplers monitoring Shanghai's growing wastewater treatment system.
Mathur adds that NI’s staffers recently threw one its Compact RIO PACs off the 9th floor of its headquarters, while the device was in the process of acquiring data, and that it still functioned properly. Compact RIO also uses Flash data storage and has no rotating parts.
“Fanless PCs allow for more protection and higher NEMA/IP ratings because no air needs to be moved out of the PC’s enclosure. This means the PC’s housing can be completely sealed,” says Falke. “This type of PC can be mounted directly in a machine, such as on a pendant arm, and eliminates the need for an industrial enclosure to house the PC. Phoenix Contact’s Vehicle Mount Terminals (VMT) are examples of these fanless, direct machine-mount PCs.”
At a time when there are so many IPC forms factors, it’s even more important now that so many are running Microsoft Windows software, according to Graham Harris, Beckhoff’s president. “Windows gives good data processing, file sharing, communications with .Net environments, and with CE for real-time controls, which doesn’t need a real-time kernel like a PLC,” says Harris. “This is another case of software being applied via the necessary hardware. As the saying goes—‘Software defines, and hardware implements.’ ”