They used to be called relays, then PLCs, then PACs (Programmable Automation Controllers) and sometimes industrial computers. The differences are more in the name and technology than the function. Don't get me wrong, there is a huge difference between what relays performed in the old days and what PACs can do today, but it is all about control of a process or machine.
Programmable logic controllers (PLCs), says Himanshu Shah, senior analyst at ARC Advisory Group, "are continually improving to meet rising challenges in functionality, communications, size, software, implementation and diagnostics. Demands for open standards, multicontrol diagnostics, modular architectures and comprehensive automation solutions software are leading to an expanding role for PLCs, especially for high-end PLC applications. Interoperability is the driving force in creating the multidisciplined controller. Consequently, a new role of the high-end PLC will shift toward the PAC. More and more, the plant floor is being populated by safety-related components and equipment for plant and factory automation."
These PACs now combine four primary control disciplines—drive, integrated motion, integrated process and sequential control—and most recently safety. Safety-related components and equipment, such as light curtains, door switches, pressure sensors and motion detectors, populate the factory floor. Instead of using two different control systems, users are installing one box that can perform both standard machine control and safety control across a single safety-related network. For Safety Integrity Level (SIL) 3 compliance within the single box, dual-processor operation is required. If a processor goes down, the other can take over in an orderly fashion and perform an orderly shutdown.
According to Research and Markets, "one of the major transformations taking place in the PLC industry is the manufacturer's consolidation of various software packages into a single, open solution. Manufacturers are now providing complete solutions based on common architectures. These user-friendly packages feature HMIs that include touch-screen or standard mouse operation or allow programming functions to be performed from a keyboard.
"The paradigm shift by manufacturing plants to PC-based controls will be a major challenge to the PLC industry. Higher processing power and lower costs for commercial PCs have accelerated the shift. Use of PC-based systems will facilitate more advanced networking among fundamentally different controllers.
"As PCs increasingly penetrate standard PLC markets, winners will be those companies that develop PC-based solutions. Larger participants are producing both PLC and softPLC solutions now."
New Products Editor
CONTROL, VISUALIZATION all IN ONE
EZTouch integrates control and visualization for small-to-medium machines that require touch-type graphical displays. The system integrates a micro modular PLC base with 32 or 64 I/O. Snap-in EZI/O module options include analog I/O, high-speed counter, relay and AC/DC combo modules. Connectivity to Ethernet TCP/IP, Profibus and DeviceNet allows the user to address remote I/O, and connect to just about any device on the plant floor.
Telemecanique brand Modicon M340 programmable automation controller (PAC) is capable of real-time logic solving and offers communication, motion, database and manipulation capabilities in multiple programming environments. It is programmed by Unity Pro, the latest IEC 61131-3 development software. The Unity suite offers a choice of IEC languages, graphic programming and online help. Users can reuse developments among the PAC platforms. This PAC integrates a high-speed USB port and offers a choice of two additional communication ports—fCANopen, Ethernet or Modbus.
Schneider Electric; 847/397-2600;
EnduraTouch industrial computers have a stainless steel NEMA 4X enclosure, conductive cooling technology and sealed I/O ports, keeping water and dust out in areas where humidity, extreme temperatures, vibration and caustic washdowns are part of everyday operations. It uses Intel Mobile processing technology and can be configured as either a thin client or a workstation. Storage options include CompactFlash and hard disk drives. Supported operating systems include Windows XP, Windows Embedded XP, Windows CE and Linux. EnduraTouch can be equipped with 802.11g wireless networking.
NET Concentrator System (NCS) has sequential control language programmability based on IEC 61131-3, including ladder, function block diagram and structural text, and has the ability to act as a single PID loop controller with simple cascade, split action and inverse capabilities. The NCS withstands ambient temperature conditions from -40 ºC to +85 ºC and -40 ºF to +185 ºF for use in harsh field environments. It comes in a DIN-rail mounted metal enclosure that protects against RFI/EMI, high vibration and shock common in heavy industrial environments.
Moore Industries-International; 818/894-7111;
PowerPC-based Embedded System Modules (ESMs) have been expanded to include a single-board computer that employ's Freescale's MPC8548, providing 1.5 GHz of processing power. Also using Altera's Cyclone II FPGA, the EM9 is a universal computer core for cost-critical embedded solutions in harsh industrial environments and provides individual I/O for each application through IP cores. Specific applications include industrial control and safety or networked systems.
MEN Micro; 215/542-9575;
Gold series Panel PCs now come preloaded with Windows XP Professional. Available in 8-in., 10-in., 15-in. and 17-in. touchscreen displays. The 8-in. PC108A costs $2,180 and includes a 40 G hard drive, 256 MB SDRAM, Windows XP operating system, Ethernet/Serial ports and CompactFlash port. The PCs come with NEMA 4 anodized aluminum front bezel and steel enclosure for use in harsh environments.
Maple Systems; 425/745-3229;
Windows Mobile 5 powered InstantPanel color TFT touch panels are available in 5.6-in., 8-in., 10.4-in. and 12.1-in. sizes. Connectivity features include three serial ports (RS232/485- configurable), Ethernet port and three USB 2.0 ports which provide a variety of communication options. The built-in CompactFlash card slot and 44-pin IDE interface give users many storage options. InstantPanel can be bundled with InstantHMI 5.0 Runtime Engine for trending, data logging, recipes, configuration, OI-Widgets, customized OEM DLL and/or user DLL.
Software Horizons; 978/670-8700;
MOVI-PLC integrates PLC control and motion control for a flexible distributed control system. The controllers incorporate a selection of pre-written and tested function blocks. The library of standard function and motion blocks is usable in any of five standard IEC 61131-3 programming languages and is compliant with the PLC open motion control standard. The scalable MOVI-PLC is available in two power classes. In the basic class, integrated interfaces for Profibus, DeviceNet, CAN and RS485 can control up to 12 axes synchronously from the system bus. In the advanced class for the top power range, up to 64 axes can be controlled by Ethernet.
LPC-350PCI PC uses Intel's Pentium and Celeron M series processors. The aluminum chassis measures just 2 in. tall having the overall footprint about the size of a hard cover novel, measuring 10 in. x 5.87 in. x 2.75 in. and weighing approximately 6 lbs. The open PCI card slot allows users to add specialized I/O, video, data acquisition and communications cards. The mini PC has a multitude of I/O connectivity built into a small design such as LAN, Serial, 3-USB 3.0, FireWire, video, audio, PS/2 mouse and keyboard ports. For applications that require extra high shock, vibration and temperature ranges, an optional solid state hard drive and Flash drive are available.
Stealth Computer; 888/STEALTH;
Where users may have dwindling support or no support for older competitive products, these monitors can act as a drop-in replacement for monitors from Rockwell/AB, Intecolor, Xycom and others. Models are available in 18 in., 19 in. and 20 in. in a variety of configurations.
Christensen Display Products; 425/222-3800;
The "SM" PCs provide a lower-cost alternative to this company's high-end "PM" version. The "SM" is available in a 12 in. touchscreen version with one slot, or a 15 in. trouchscreen version with three slots. Selected connectivity options include three onboard USB 2.0 ports, internal PCI bus with 3.3 V and 5 V voltages to support most PCI-bus interface cards and an all-metal design.
Phoenix Contact; 800/888-7388;
AWS-8129H PC-based industrial workstation offers a 12.1 in. color TFT LCD display. Included are three ISA, four PCI and two PIC slots. There is a PS/2 port, USB port, floppy disk drive and an optional CD-ROM drive behind a front-accessible protective door. There are two membrane keypads. The first one has 47 operating keys including 26 alpha characters; the second one has 10 function keys, 10 programmable macro function keys, reset and power on/off. There are six OSD keys and a touchpad with no mouse buttons. The operating system supports Window 95, 98, 2000 and XP. Designed for harsh environments, the workstation is RoHS compliant for NEMA 4/IP65 applications.
Advantech, eAutomation Group; 513/742-8895;