rick_pedraza

Evolution, Not Revolution, for Programmble Controls

May 10, 2006
A Product Roundup of new programmable control devices and components shows that improvements in capabilities are keeping pace with discrete machine applications for various emerging markets.
About the Author
In 2006, Rick Pedraza was digital managing editor for Control Design.After another year of robust market growth, forecasts for the use of programmable controllers in discrete machine applications is expected to rise once again due to heightened demand from various emerging markets.

According to a recent study by ARC Advisory Group, the outlook through 2009 identifies booming markets in Asia and Latin America as regions of new opportunities for programmable controls used for condition monitoring, safety, collaborative manufacturing, and real-time optimization.

ARC’s analysis of current market stats shows global purchases of PLCs are expected to grow at a Compounded Annual Growth Rate (CAGR) of 5.9% over the next five years, taking worldwide sales figures of controller devices from just over $7 billion in 2005 to more than $9 billion in 2009.

It appears that most users are asking for steady product improvement, not huge, step-change advances. Many industry professionals agree that the continuing overlap of PC, PLC, and embedded technology capabilities will enable more-efficient control, faster cycle times and ease of connectivity.

According to research provided by Frost & Sullivan, “the paradigm shift by manufacturing plants to PC-based controls also will become a major challenge to the PLC industry. Globalization is increasingly causing manufacturers to favor automation expenditure to drive down costs and raise the quality of products while addressing consumer demand and infrastructure development,” the report says. Higher processing power and lower costs for commercial PCs is accelerating the shift to PC-based systems, studies show. Furthermore, the use of PC-based systems is facilitating more advanced networking among fundamentally different controllers.

That observation should be absorbed cautiously. The impending demise of the PLC has been postponed many times, usually due to its faithful use by “stubborn” machine builders, SIs, and end users alike. Micro and nano PLC manufacturers should see the most growth, researchers at Frost concluded, as machine builders specify devices that occupy less space in their designs with the same performance capabilities as larger systems.

Our roundup of programmable controllers new to the market shows that ease of programming, reliability, and the ability to provide real-time operating data are the hot buttons. Included here are hardware devices that have new or improved functionalities, including advanced timer commands, PID loop commands, motion commands, and Ethernet compatibility. In addition, as PLCs become more and more capable, they increasingly take on more supervisory responsibility in control system design.

Product Roundup:

Programmable Controllers

Get On Board
PC/104-Plus single-board computer features a 1.6 GHz Pentium M processor for embedded control applications. The 3.6x3.8 in. board includes two COM ports, two USB 2.0 ports, Ethernet, IDE, LPT, audio, and PS/2 keyboard/mouse support. Standard pass-through connectors allow it to be stackable. The system includes customizable, OEM-enhanced BIOS that is field-upgradeable, and is designed to work with embedded operating systems including Windows CE/XP/XPe, Linux, VxWorks, QNX, and DOS. VersaLogic; 541/485-8575; www.VersaLogic.com

Universal Control
Single-loop PID process controller monitors and controls temperature, pressure, level, flow and other analog variables for batch and continuous processes. Available models provide an isolated analog (4-20 mA or 0-20 mA) control signal output to regulate a control valve or similar final control element. Models with alarm trip outputs can be used for on/off control or to warn of unwanted high/low conditions. Optional RS-485 communications allows interface with digital-communicating DCS, PLC and PC-based SCADA systems. Moore Industries; 818/894-7111; www.miinet.com

Logical Deployment
MVI56-ADM and MVI56-ADMNET modules available in both serial and Ethernet feature two jumper configured ports for direct or multi-drop field communication (supporting RS-232, RS-422 and RS-485) and one debug port for setup, configuration and diagnostics. Independent control of the two application ports allows for flexibility and expandability in the design. Memory usage is user-configurable, supporting the storage and transfer of up to 5,000 registers to/from the control processor. ProSoft Technology; 661/716-5100; www.prosoft-technology.com

It’s Your Move
NextMove e100 motion controller provides real-time control, onboard analog and digital I/O and a USB port for simple connection to PC hosts with ActiveX support tools. Additionally included are support for three traditional analog-controlled servos and four steppers, and a CANopen interface for adding local or remote I/O or other components. It links seamlessly into local and wide-area networks, and provides simpler system building and commissioning. Baldor; 800/828-4920; www.baldor.com

Blue Programming
Twido nano controller with embedded Ethernet capability can be programmed with Bluetooth wireless or Ethernet, simplifying diagnostics and troubleshooting for OEMs and plant personnel. Features include four high-density analog I/O expansion modules that provide options for measurement and regulation. Capabilities include 40 I/O compact controllers with an embedded real-time clock and a compartment for a replaceable external back-up battery. Schneider Electric; 800/392-8781; www.us.telemecanique.com

Keep Discrete
Micro-VersaTrak µIPm RTU/controller has a built-in mix of 14 discrete and analog I/O, four serial ports and a 10/100 Ethernet interface. It is pre-loaded with open-source Linux and industrial IPm firmware. It can be used for real-time inventory management such as RFID systems, HVAC and energy management, or environmental monitoring. Programming can be done using any mix of languages (ladder logic, sequential function chart, etc.), high-level C/C++ and more. It has 16 MB of flash disk and 16 MB of fast dynamic memory, along with an industrial PowerPC CPU. Sixnet; 518/877-5173; www.sixnetio.com

Flying Solo
Soloist single-axis servo controller combines a power supply, amplifier, and position controller to handle complex functions such as output-on-the-fly and velocity profiling. It controls up to four tasks simultaneously, handles variables, manages I/O, and has high-speed position-latch inputs and advanced data-logging capabilities. HMI software provides a platform for controlling the entire process, and a Windows-based interface has diagnostic, development, and analysis tools for OEMs and end users. Aerotech; 412/963-7470; www.aerotech.com

Control the Bus
KL2532 and KL2542 I/O terminals provide an alternative to traditional drive systems for DC motors. Two 24 W DC motors can be supplied with up to 1 A, and short-term peak currents are permitted for fast acceleration. Terminals contain all features of a full interface between motion control software and the mechanical system. Additional parameters such as maximum peak current and speed, internal resistance of the motor, or acceleration ramps can be set via the fieldbus. Beckhoff Automation; 952/890-0000; www.beckhoffautomation.com

Moving to a Duplex
CS1D duplex programmable controller adds redundancy for critical processes and systems. It automatically switches control to the second unit within one program scan, enabling continuous operation. The down CPU can be changed out while operation continues. Redundant power supply and communication modules can be removed and replaced without interrupting control operation. Continuous operation is further enhanced by hot-swappable I/O and specialty modules. Omron Electronics; 866-88/OMRON; www.omron.com/oei

New to the Family
PLC-5 Series F Ethernet processor provides enhanced Ethernet communications and messaging, remote monitoring and management, IT integration, voice and video. Capabilities include auto-negotiating between 10-100 Mbps. The processor includes an RJ45 connector located on the faceplate, allowing direct connection of CAT-5 Ethernet cabling while eliminating the need for an external transceiver. Rockwell Automation; 800/223-5354; www.ra.rockwell.com

Spies Like Us
SPiiPlus control module combines a multi-axis motion controller and integrated digital servo amplifiers. Features include internal digital drives with space vector modulation; PIV control with programmable notch and second-order low-pass filters; 20 kHz sampling rate on position, velocity, current and commutation loops; 10/100BaseT Ethernet and RS-232/422/485; and Windows tools for tuning and troubleshooting. A complete motion simulator develops applications without hardware. ACS-Tech80; 800/545-2980; www.acs-tech80.com

Don’t Bug Me
S2E/S2T programmable controllers offer on-line debug functions such as input force, coil force, data set, status latch and sample trace. Any program written for a T-Series CPU can be downloaded directly into the PLC without modification. Device/register tags and comments can be stored in CPU module. Tags and comments can be viewed in the on-line mode without access to the original program. Programs can be created without consideration for memory constraints. Toshiba; 800/316-0920; www.toshiba.com

Small but Smart
MicroSmart series PLC has PID control, four built-in 20 kHz counters and two built-in 20 kHz pulse outputs. It has a large program size and communicates with an operator interface through a RS232C/RS485 port. Choose brick or book-style CPU and configure up to a maximum of 264 I/O. The PLCs are programmable with WindLDR intuitive ladder-logic software, and are cULus, CE, Lloyds and Class 1 Div 2 hazardous locations approved. IDEC; 800/262-IDEC; www.idec.com

System Controls Nip Force
RCS-microPOS digital servo force and positioning control reeling system is used to adjust the primary arms’ relief cylinders to the correct linear nip force on the winder of paper machines. The system measures and controls the actual nip forces using specially designed load cells, rather than inferred forces from cylinder pressures, and control is true closed-loop. Control during operation is carried out via the digital inputs on the RCS from a PLC or directly from the operator’s console. Vishay; +44(0)29 2055 5093; www.vishay.com