Showing posts with label process instrument. Show all posts
Showing posts with label process instrument. Show all posts

Sunday, December 17, 2017

Process Control Basics: The Underlying Principle Behind Coriolis Flowmeters

The Coriolis effect, a derivative of Newtonian motion mechanics, describes the force resulting from the acceleration of a mass moving to (or from) the center of rotation. As this video demonstrates, the flowing water in a loop of flexible hose that is “swung” back and forth in front of the body with both hands. Because the water is flowing toward and away from the hands, opposite forces are generated and cause the hose to twist. Coriolis flowmeters apply this principle to measure fluid flow.


For more information on any process flow application, contact Mead O'Brien by calling
(800) 892-2769
or by visiting https://www.meadobrien.com.

Monday, August 21, 2017

HART Communication Protocol - Process Instrumentation

HART process instruments
Process instrument with HART protocol (Foxboro)
The Highway Addressable Remote Transducer Protocol, also known as HART, is a communications protocol which ranks high in popularity among industry standards for process measurement and control connectivity. HART combines analog and digital technology to function as an automation protocol. A primary reason for the primacy of HART in the process control industry is the fact that it functions in tandem with the long standing and ubiquitous process industry standard 4-20 mA current loops. The 4-20 mA loops are simple in both construction and functionality, and the HART protocol couples with their technology to maintain communication between controllers and industry devices. PID controllers, SCADA systems, and programmable logic controllers all utilize HART in conjunction with 4-20 mA loops.

HART instruments have the capacity to perform in two main modes of operation: point to point, also known as analog/digital mode, and multi-drop mode. The point to point mode joins digital signals with the aforementioned 4-20 mA current loop in order to serve as signal protocols between the controller and a specific measuring instrument. The polling address of the instrument in question is designated with the number "0". A signal specified by the user is designated as the 4-20 mA signal, and then other signals are overlaid on the 4-20 mA signal. A common example is an indication of pressure being sent as a 4-20 mA signal to represent a range of pressures; temperature, another common process control variable, can also be sent digitally using the same wires. In point to point, HART’s digital instrumentation functions as a sort of digital current loop interface, allowing for use over moderate distances.

HART in multi-drop mode differs from point to point. In multi-drop mode, the analog loop current is given a fixed designation of 4 mA and multiple instruments can participate in a single signal loop. Each one of the instruments participating in the signal loop need to have their own unique address.

Since the HART protocol is a standardized process control industry technology, each specific manufacturer using HART is assigned a unique identification number. This allows for devices participating in the HART protocol to be easily identified upon first interaction with the protocol. Thanks to the open protocol nature, HART has experienced successive revisions in order to enhance the performance and capabilities of the system relating to process control. The standardization of “smart” implementation, along with the ability to function with the legacy 4-20 mA technology and consistent development, has made HART a useful and popular component of the process measurement and control industry framework.

Have a question about HART? Contact Mead O'Brien by visiting this link, or call
(800) 892-2769.

Monday, July 24, 2017

Mead O'Brien: Experts in Valves, Valve Automation, Steam & Hot Water Systems, Process Instruments

Mead O’Brien specializes in valves & valve automation, steam & hot water products and systems, instrumentation products, skid designs, field services, surveys, assessments, and consulting.

Product Focus:
  • Valves, valve automation and control
  • Steam and hot water products and systems
  • Instrumentation and controls
For more information, visit http://www.meadobrien.com or call  (800) 892-2769.

Please pardon our little shameless self-promotion. Thanks for watching this short video highlighting Mead O'Brien products.

Friday, March 31, 2017

Intelligent Transmitters Help Coal Plant Reduce Costs and Improve Performance

Power Plant
Effective, profitable power plant operation requires managing capital-expense turbine, boiler, and combustion equipment, along with many other assets that must be precisely balanced. Reliable readings of pressure, temperature, and other process variables are critical to success.

While analog transmitters are known for accuracy and reliability, maintenance costs increase with age, and flexibility for performance improvement is limited. To reduce long-term operating costs and maintain quality service to more than 300,000 customers, a Michigan power utility launched a program to replace its aging analog transmitters with modern digital models.

The utility uses transmitters for draft indications on the boiler and pulverized mill area. They read pressure on the boiler and the turbine as well as combustion and steam heating equipment. Some of the instruments send data to a centralized distributed control system (DCS), which manages the set points that control the sensitive interactions. Other instruments simply indicate various pressure states to operators and maintenance technicians.

When this power utility implemented its first DCS, all transmitters were analog. At the time, mixing and matching multiple brands of analog sensors was difficult, and in some cases impossible, due to proprietary mounting configurations. Managers at this Michigan power plant wanted to be certain that they selected a digital sensor that would not lock them into a single vendor.

To learn how this power company came up with a the solution and to learn the results, read the complete document below. For any process instrument requirement, visit Mead O'Brien at www.meadobrien.com or call (800) 892-2769.

Friday, April 29, 2016

Choose Guided Wave Radar for Your Challenging Process Level Application

Guided Wave Radar transmitters (GWR)
Guided Wave
Radar Transmitter
Courtesy of
Foxboro/Schneider
Electric
Designed to perform continuous level measurement in a wide range of industries and applications, Guided Wave Radar transmitters (GWR) are unaffected by changes in temperature, specific gravity, pressure and with no need to recalibrate, offering a highly available measurement at low maintenance cost. GWR transmitters provide level measurement solutions in a variety of process applications, providing a universal radar measurement solution for all liquids including corrosive, viscous, sticky and other difficult media such as foam and turbulent surfaces, and solids.

Electromagnetic pulses are emitted and guided along a probe.  These pulses are reflected back at the product surface.  The distance is calculated by measuring this transit time. This device is perfect for high-end applications.  It is suitable for applications with foam, dust, vapor, agitated, turbulent or boiling surfaces with rapid level changes.

Common features include:
Easy configuration via digital communication; Wide selection of materials facilitates service under harsh/corrosive conditions; Solutions for density/pressure variations and rapid level changes; Empty Tank Spectrum filtering; Quick Noise scanning reduces false radar reflections.

Applications: Steam Generation /Boiler Drum; Oil/Water Separator; BioDiesel Production; Overflow Protection; Interface and Density; Process tanks; Storage tanks; Polyester/Nylon fiber production; Claus Process


For more information on Guided Wave Radar level instruments, contact:

Mead O'Brien
(800) 892-2769
www.meadobrien.com

Thursday, October 15, 2015

Innovative Pressure Transmitter Automatically Selects Calibration Range

Foxboro S Series
Foxboro S Series
Typical 2-wire intelligent transmitters require the operator to manually program and use a single calibration range suited to the specific application. Not anymore. A winner of a 2015 Flow Control Innovation Award has come up with a significant change in transmitter set-up.

Foxboro, through its patented “Foxcal” firmware allows the Foxboro models IDP10S, IGP10S, IAP10S transmitters to automatically select and use any of 11 preset calibration ranges (stored in firmware). These calibration ranges cover the full pressure range of the transmitter. Upon installation, the S Series transmitter automatically selects the appropriate calibration range based on application inputs; and, if application inputs change, automatically transitions to another, more appropriate calibration range – all while maintaining a reference accuracy of 0.05%.

It is the first pressure transmitter to incorporate not only multiple calibration curves, but the ability to automatically select and transfer between them in real time. With the new technology, users have a wide-range capability with high reference accuracy for all industries requiring precise differential, gauge, and absolute pressure measurement. Additional benefits are inventory reduction and simplified tech training. Because of their wide turndown range with such high reference accuracy, adopting one model of S Series transmitter eliminates the need to inventory, learn, and maintain multiple transmitter models that handle more limited ranges (e.g., 150 psi, 800 psi, 4000 psi).

The Foxboro IDP10S datasheet can be downloaded here.

Or, you can review it online below:


For more information, contact:
Mead O’Brien
(800) 892-2769
sales@meadobrien.com
www.meadobrien.com