Emerson acquires EIM Controls

Emerson Process Management acquired Missouri City, Texas, USA, based EIM Controls Inc., a manufacturer of high-quality valve actuators. EIM Controls will join the company’s Valve Automation division, expanding Emerson’s electric actuator portfolio, while strengthening the company’s applications for FOUNDATION fieldbus and other major bus protocols.

“This is a strategic acquisition that adds value and strengthens our position in the competitive automation market,” said Dan Button, president of Valve Automation. “EIM Controls brings to Valve Automation a well-known reputation for reliability and extensive product line that perfectly complements our PlantWeb digital plant architecture.”

The addition of EIM Controls brings Multi-turn and Quarter-turn actuators incorporating MCP, M2CP, TEC2000 and the ECP2000 electric and electronic controls into Emerson's portfolio.

Since 1949, EIM Controls Inc. has pioneered product innovation and design in the manufacturing of electric valve actuators. The company generated approximately $43.3 million (€29 million) in annual sales for the period ending September 30, 2009, and has 168 employees throughout the United States, Europe and Asia.

HONEYWELL INTRODUCES ISA100.11a-READY WIRELESS RADAR GAUGE

Device Increases Flexibility While Lowering Installation Costs by Capturing Wide Range of Tank Measurements

DELFT, THE NETHERLANDS, – Honeywell (NYSE:HON) today released the first ISA100.11a-ready wireless radar gauge that helps process manufacturers monitor tank levels and prevent hazardous incidents in their plants and terminals. The FlexLine Wireless Radar Gauge improves operator awareness by capturing a wide array of tank measurements and quickly transmitting them via the OneWireless™ network to control rooms. This reduces overall operating costs and improves safety by eliminating the need for manual data collection.
The gauge is the latest addition to Honeywell’s growing OneWireless family of industrial wireless solutions for the process industries. Based on equipment compatible with the ISA100.11a standard, OneWireless networks can simultaneously accommodate multiple wireless protocols and thousands of field devices ranging from transmitters and gauge readers to mobile handheld devices and RFID tags.
In addition to level measurement, the FlexLine Wireless Radar Gauge can track temperature, pressure, water and overfill. This eliminates the need for multiple gauges and transmitters, which further reduces installation costs and increases flexibility by enabling new measurements without additional wiring. The gauge also has passed the highest accuracy and security standards set by The Dutch Weight and Measurement (W&M) authority, a key designation for the device to be used for loading and unloading tank liquids from ships and trucks. In addition to meeting the Dutch standards, the gauge has been submitted for review by W&M authorities in several other countries.
“Terminals today are striving for more efficient production, which means operators need more information and diagnostics from the field to better understand how their assets are functioning,” said John Joosten, radar and safety product manager, Honeywell Enraf. “The FlexLine Wireless Radar Gauge enables plants to easily obtain this information, making the device an ideal solution to increase uptime, efficiency and safety for facilities with challenging infrastructures.”
For more information regarding the FlexLine Wireless Radar Gauge and other Honeywell field instruments that improve safety, reliability and efficiency, please visit www.honeywell.com/ps.
Honeywell International (http://www.honeywell.com/) is a Fortune 100 diversified technology and manufacturing leader, serving customers worldwide with aerospace products and services; control technologies for buildings, homes and industry; automotive products; turbochargers; and specialty materials. Based in Morris Township, N.J., Honeywell’s shares are traded on the New York, London, and Chicago Stock Exchanges. For more news and information on Honeywell, please visit http://www.honeywellnow.com/. Honeywell Process Solutions is part of Honeywell’s Automation and Control Solutions group, a global leader in providing product and service solutions that improve efficiency and profitability, support regulatory compliance, and maintain safe, comfortable environments in homes, buildings and industry. For more information about Process Solutions, access www.honeywell.com/ps.
This release contains “forward-looking statements” within the meaning of Section 21E of the Securities Exchange Act of 1934. All statements, other than statements of fact, that address activities, events or developments that we or our management intend, expect, project, believe or anticipate will or may occur in the future are forward-looking statements. Forward-looking statements are based on management’s assumptions and assessments in light of past experience and trends, current conditions, expected future developments and other relevant factors. They are not guarantees of future performance, and actual results, developments and business decisions may differ from those envisaged by our forward-looking statements. Our forward-looking statements are also subject to risks and uncertainties, which can affect our performance in both the near- and long-term. We identify the principal risks and uncertainties that affect our performance in our Form 10-K and other filings with the Securities and Exchange Commission.

Industrial Video & Control introduces Thermal Imaging IP camera

Industrial Video & Control announced a high-resolution thermal imaging IP camera ideal for low-light or no-light locations. The camera is housed in a pressurized outdoor enclosure making it suitable for use in harsh environments.

The thermal imager is housed in an enclosure that is rated NEMA 6P, IP68. The assembly is pressurized and has a wide operating temperature range making useful in almost any environment. When used with IVC’s camera management software, this camera provides both local and remote monitoring of public, industrial, and marine facilities. The camera can detect human activity up to about 2,500 feet away.

IVC camera offering includes pan-tilt zoom, fixed, auto-zoom and varifocal (manual zoom) cameras.

Honeywell To Help Boost Efficiency At Sugar Plant

Honeywell has announced it has been awarded a three-year maintenance and support contract with Turkey's largest private sugar producer, Konya Sugar. As part of the Solution Enhancement Support Program (SESP) contract, Honeywell will upgrade the Experion process knowledge system (PKS) at Konya Sugar's Cumra production site. SESP is Honeywell's core system support programme that helps customers keep automation investments up to date.

In addition, SESP provides several support mechanisms that can improve the performance and uptime of automation systems, such as training for engineers and operators, access to Honeywell's on-line knowledge base, and access to the experts in the technical assistance centre to assist with troubleshooting. 'We selected Honeywell after seeing significant improvements in product quality and production capacity as well as a reduction in production costs with the earlier implementation of Experion,' said a representative of Konya Sugar's Cumra site management.

Honeywell's SESP for Konya Sugar will help the company maintain peak operating performance and maximise the long-term value of the company's control systems and installed solutions. The SESP contract is designed to meet the needs of the Cumra site and includes software updates to the installed system to maintain optimum performance. Honeywell will also upgrade Konya Sugar's existing Experion to the latest release, Experion R310. This upgrade should allow the site to increase productivity and decrease maintenance costs, with up to 50 per cent better return on investment over the facility's lifecycle due to faster access to process information, a decrease in shutdowns, and quicker recovery from process upsets. The factory will also have access to 24/7 on-site technical assistance.

Tyco Grounding Connector Cuts Installation Time

Tyco Electronics has introduced a grounding connector that shortens the installation time of a ground wire to a solar panel frame. The threaded connector is inserted through a hole in the frame and uses two hex nuts to help provide a reliable connection.

The connector handles six and 8AWG (13.3 and 8.4mm2) solid uninsulated copper wire. In connecting to the frame, the connector body and the one-piece lock washer nut penetrate the surface of the aluminium frame, helping to create a reliable ground path.

In the six-second short-term current test, the connector handles 1,530A with a 6AWG ground wire. With an 8AWG ground wire, a four-second test concludes that the connector handles 1,180A. In UL 486A/B pull-out testing, the connector provides 100lb (45.3kg) with a 6AWG wire and 90lb (40.8kg) with an 8AWG wire.

GeoThermal Power Plants

There are three geothermal power plant technologies being used to convert hydrothermal fluids to electricity. The conversion technologies are dry steam, flash, and binary cycle. The type of conversion used depends on the state of the fluid (whether steam or water) and its temperature. Dry steam power plants systems were the first type of geothermal power generation plants built. They use the steam from the geothermal reservoir as it comes from wells, and route it directly through turbine/generator units to produce electricity. Flash steam plants are the most common type of geothermal power generation plants in operation today. They use water at temperatures greater than 360°F (182°C) that is pumped under high pressure to the generation equipment at the surface. Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units.

Dry Steam Power Plants

Steam plants use hydrothermal fluids that are primarily steam. The steam goes directly to a turbine, which drives a generator that produces electricity. The steam eliminates the need to burn fossil fuels to run the turbine. (Also eliminating the need to transport and store fuels!) This is the oldest type of geothermal power plant. It was first used at Lardarello in Italy in 1904, and is still very effective. Steam technology is used today at The Geysers in northern California, the world's largest single source of geothermal power. These plants emit only excess steam and very minor amounts of gases.
Flash Steam Power Plants

Hydrothermal fluids above 360°F (182°C) can be used in flash plants to make electricity. Fluid is sprayed into a tank held at a much lower pressure than the fluid, causing some of the fluid to rapidly vaporize, or "flash." The vapor then drives a turbine, which drives a generator. If any liquid remains in the tank, it can be flashed again in a second tank to extract even more energy.

Binary-Cycle Power Plants

Most geothermal areas contain moderate-temperature water (below 400°F). Energy is extracted from these fluids in binary-cycle power plants. Hot geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point than water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines. Because this is a closed-loop system, virtually nothing is emitted to the atmosphere. Moderate-temperature water is by far the more common geothermal resource, and most geothermal power plants in the future will be binary-cycle plants.

The Future of Geothermal Electricity

Steam and hot water reservoirs are just a small part of the geothermal resource. The Earth's magma and hot dry rock will provide cheap, clean, and almost unlimited energy as soon as we develop the technology to use them. In the meantime, because they're so abundant, moderate-temperature sites running binary-cycle power plants will be the most common electricity producers.

Before geothermal electricity can be considered a key element of the U.S. energy infrastructure, it must become cost-competitive with traditional forms of energy. The U.S. Department of Energy is working with the geothermal industry to achieve $0.03 to $0.05 per kilowatt-hour. We believe the result will be about 15,000 megawatts of new capacity within the next decade.

Loop Tuning Fundamentals

PID loop tuning may not be magic, but its intricacies do lie somewhere between science and art. The following proven tuning tips will help you craft your processes.

A control loop is a feedback mechanism that attempts to correct discrepancies between a measured process variable and the desired setpoint. The controller applies the necessary corrective actions via an actuator that can drive the process variable up or down.

A proportional-integral-derivative (PID) controller tracks the error between the process variable and the setpoint, the integral of recent errors, and the rate by which the error has been changing. It computes its next corrective action from a weighted sum of those three terms (or modes), then outputs the results to the process and awaits the next measurement.

PID basics

A PID controller using the ideal or ISA standard form of the PID algorithm computes its output CO(t) according to the formula shown in Figure 1. PV(t) is the process variable measured at time t and the error e(t) is the difference between the process variable and the setpoint. The PID formula weights the proportional term by a factor of P, the integral term by a factor of P/T _I, and the derivative term by a factor of P. T _D where P is the controller gain, T _I is the integral time, and T _D is the derivative time.

This terminology bears some explaining. Gain refers to the amount by which the error signal will gain or lose strength as it passes through the controller en route to becoming part of the controller's output. A PID controller with a high gain will tend to generate aggressive corrective actions to eliminate errors.

The integral time refers to a hypothetical sequence of events where the error starts at zero then abruptly jumps to a fixed value. Such an error would cause an instantaneous response from the controller's proportional term and a response from the integral term that starts at zero and increases steadily. The time required for the integral term to catch up to the unchanging proportional term is the integral time T _I. A PID controller with a long integral time is more heavily weighted towards proportional action thanintegral action.

Similarly, the derivative time T _D is a measure of the relative influence of the derivative term in the PID formula. If the error were to start at zero and begin increasing at a fixed rate, the proportional term would start at zero while the derivative term assumed a fixed value. The proportional term would then increase steadily until it caught up to the derivative term at the end of the derivative time. A PID controller with a long derivative time is more heavily weighted towards derivative action than proportional action.

Historical note

The very first feedback controllers included just the proportional term. For mathematical reasons that only became apparent later, a P-only controller tends to drive the error downward to a small but non-zero value and then quit. Operators observing this phenomenon would then manually increase the controller's output until the last vestiges of the error were eliminated. They called this operation resetting the controller.

When the integral term was introduced, operators observed that it tended to perform the reset operation automatically. That is, the controller would augment its proportional action just enough to eliminate the error entirely. Hence, integral action was originally called automatic reset and remains labeled that way on some PID controllers to this day. The derivative term was invented shortly thereafter and was described, accurately enough, as rate control.

Tricky business

Tuning is the art of selecting values for the tuning parameters P, T _I, and T _D so that the controller will be able to eliminate an error quickly without causing the process variable to fluctuate excessively. That's easier said than done.

Consider a car's cruise controller, for example. It can accelerate the car to a desired cruising speed, but not instantaneously. The car's inertia causes a delay between the time that the controller engages the accelerator and the time that the car's speed reaches the setpoint. How well a PID controller performs depends in large part on such lags.

Suppose an overloaded car with an undersized engine suddenly starts up a steep hill. The ensuing error between the car's actual and desired speeds would cause the controller's derivative and proportional actions to kick in immediately. The controller would begin to accelerate the car, but only as fast as the lag allows.

After a while, the integral action would also begin to contribute to the controller's output and eventually come to dominate it (since the error decreases so slowly when the lag time is long, and a sustained error is what drives the integral action). But exactly when that would happen and how dominant the integral action would become thereafter would depend on the severity of the lag and the relative sizes of the controller's integral and derivative times.

This simple example demonstrates a fundamental principle of PID tuning. The best choice for each of the tuning parameters P, T _I, and T _D depends on the values of the other two as well as the behavior of the controlled process. Furthermore, modifying the tuning of any one term affects the performance of the others since the modified controller affects the process and the process, in turn, affects the controller.

Ziegler-Nichols tuning

So how can a control engineer designing a PID loop determine the values for P, T _I, and T _D that will work best for a particular application? John G. Ziegler and Nathaniel B. Nichols of Taylor Instruments (now part of ABB Instrumentation in Rochester, NY) addressed that question in 1942 when they published two loop-tuning techniques that remain popular to this day.

Their open-loop technique is based on the results of a bump or step test for which the controller is taken off-line and manually forced to increase its output abruptly. A strip chart of the process variable's subsequent trajectory is known as the reaction curve (see Figure 2).

A sloped line drawn tangent to the reaction curve at its steepest point shows how fast the process reacted to the step change in the controller's output. The inverse of this line's slope is the process time constant T which measures the severity of the lag.

The reaction curve also shows how long it took for the process to demonstrate its initial reaction to the step (the dead time d) and how much the process variable increased relative to the size of the step (the process gain K). By trial-and-error, Ziegler and Nichols determined that the best settings for the tuning parameters P, T _I, and T _D could be computed from T, d, and K as follows:

Once these parameter settings have been loaded into the PID formula and the controller returned to automatic mode, the controller should be able to eliminate future errors without causing the process variable to fluctuate excessively.

Ziegler and Nichols also described a closed loop-tuning technique that is conducted with the controller in automatic mode, but with the integral and derivative actions shut off. The controller gain is increased until even the slightest error causes a sustained oscillation in the process variable (see Figure 3).

The smallest controller gain that can cause such an oscillation is called the ultimate gain P _u. The period of those oscillations is called the ultimate period T _u. The appropriate tuning parameters can be computed from these two values according to the following rules:

P = 0.6 · P_u

T_I = 0.5 · T_u

T_D = 0.125 · T_u

Caveats

Unfortunately, PID loop tuning isn't really that simple. Different PID controllers use different versions of the PID formula, and each must be tuned according to the appropriate set of rules. The rules also change when:

• The derivative and/or the integral action are disabled.
• The process itself is inherently oscillatory.
• The process behaves as if it contains its own integral term (as is the case with level control).
• The deadtime d is very small or significantly larger than the time constant T.

Furthermore, Ziegler and Nichols had a particular closed-loop performance objective in mind when they settled on their particular tuning rules. They chose to allow some fluctuations in the process variable so long as each successive peak was no more than one-fourth the size of its predecessor (so-called quarter wave decay). For applications that require even less fluctuation, additional tweaking of the tuning parameters is required.

This is where loop tuning becomes an art. It takes more than a little experience and sometimes a lot of luck to come up with just the right combination of P, T _I, and T _D.

Distributed Control System (DCS)

The DCS is a control system which collects the data from the field and decides what to do with them. Data from the field can either be stored for future reference, used for simple process control, use in conjunction with data from another part of the plant for advanced control strategies.

What must be in the DCS for it to be able to do so much?

Operator Console
These are like the monitors of our computers. They provide us with the feedback of what they are doing in the plant as well as the command we issue to the control system. These are also the places where operators issue commands to the field instruments.

Engineering Station
These are stations for engineers to configure the system and also to implement control algorithms.

History Module
This is like the harddisk of our PCs. They store the configurations of the DCS as well as the configurations of all the points in the plant. They also store the graphic files that are shown in the console and in most systems these days they are able to store some plant operating data.

Data Historian
These are usually extra pieces of software that are dedicated to store process variables, set points and output values. They are usually of higher scanning rates than that available in the history module.

Control Modules
These are like the brains of the DCS. Specially customized blocks are found here. These are customized to do control functions like PID control, ratio control, simple arithmetic and dynamic compensation. These days, advanced control features can also be found in them.

I/O
These manage the input and output of the DCS. Input and output can be digital or analogues. Digital I/Os are those like on/off, start/stop signals. Most of the process measurements and controller outputs are considered analogue. These are the points where the field instruments are hard-wired to.

All above mentioned elements are connected by using a network, nowadays very often used is Ethernet.

The practical and technological boundaries between a Distributed Control System DCS, Programmable Logic Controller PLC and Personal Computer PC control are blurring. Systems traditionally associated with process control are being used in discrete applications. Likewise, traditionally discrete solutions are used increasingly in both batch and continuous process control.

Today's control hardware are constructed from many of the same standard industry components such as Intel processors. Therefore the only real difference between control systems is at the software level.