Tuesday, August 15, 2017

In Situ Oxygen Analyzer



Watch this video from Rosemount Analytical. A product manager outlines the operation and application of the model 6888 in situ oxygen analyzer. Share your process analytical challenges with the process measurement and control specialists at Hile Controls of Alabama for practical and effective solutions. The combination of your process knowledge and experience with the input of a product application specialist will yield effective solutions.

Thursday, August 10, 2017

Controlling Steam Heat Trace Lines

steam tracing temperature regulator valve
Specialty control valve regulates temperature
in steam heat tracing lines.
Image courtesy Jordan Valve
Steam is a commonly employed heat source for freeze protection or other heat tracing of process lines. Other than being an efficient heat transfer medium, steam provides the advantage of not being a possible source of ignition, extremely useful in areas where the presence of flammable vapors is a possibility.

Regardless of the method used to deliver heat, all heat trace operations consume energy. Control of the heat trace operation not only saves cost through energy conservation, but prevents potential deterioration, through overheating, of materials that may be in proximity to the heated line.

When steam is used, a well designed temperature regulator can provide control of steam flow through the heating system. Specially adapted for heat tracing operations, the Jordan Valve Mark 86 senses ambient temperature and adjusts steam flow as the ambient temperature changes. The completely self-contained unit includes temperature sensing element, diaphragm, and a sliding gate valve to regulate steam flow.

More detail is provided in the document included below. Share all your fluid flow control challenges and requirements with a flow control specialist, combining your own knowledge and experience with their product application expertise to develop an effective solution.


Friday, August 4, 2017

Industrial Wireless is a Mainstream Connection Method For Process Measurement

industrial wireless transmitter or receiver
Industrial wireless transmitters and receivers are
compact and easy to apply
Image courtesy of IOSelect
Wireless connections to process instrumentation have evolved to a point where they are uncomplicated and inexpensive to implement. Many facilities rely on wireless connections, either via a network (wifi) or point to point communications. The benefits of wireless are well known to those already among users of the technology.
  • Safety: Wireless connections can reduce personnel exposure to hazardous environments or situations that previously required human intervention or a manual gauge or instrument reading.
  • Easy Scale-up: Adding points on a network is generally a simple incremental process.
  • Operational Advantage: When deployed to replace manual instrument or gauge readings, real time data for diagnostics and efficiency measurements are now available. Information that is more accurate, timely, and consistent will produce better results.
  • Installation Savings: Installation of wireless connected assets has been reported to be up to 10 times less expensive than wired installation. The reduced space and planning for cables and conduit can make what were once complex and time consuming operations much quicker and easier.
  • Mobility: Wireless technology allows for real time connections to mobile platforms. Whether within a plant, on the road, or on the high seas, there are wireless products that can make the connection.
  • Distance: Don't just think WiFi, think radio, think satellite, think cellular. Connections can be established across very long distances using standard products from the industry.
  • Conversion of Legacy Devices: Many existing in-place devices can have their wired connections replaced with a wireless version. This accommodates a staged transition from wired to wireless in facility.
The transmission is accomplished in either the 900 MHz or 2.4 GHz band, delivering adequate range and power for most facility-wide applications. Obstructions can be overcome with the use of a strategically located repeater. Properly planned and configured, there are few limits to the distance a wireless connection can span.
Point to point wireless connections between, for example, a temperature transmitter and a recorder are easy to create. Most process sensors have very small power requirements, as do the wireless transmission and reception units. Power, if line voltage is not available at the location, can be provided by batteries, or combination of battery and photovoltaic. The 4-20 mA signal from the temperature transmitter serves as the input signal to the wireless transmitter. The analog signal is converted to a digital value and encrypted prior to transmission. A receiver at the recorder decrypts the digital signal and converts it back to a 4-20 mA analog output that serves as the input signal to the recorder. Wireless transmitter and receiver must be set to the same channel, but otherwise, the equipment handles all the work. If you can find your way around a smart phone, you can make a wireless point to point process connection.

There are likely many applications going unfulfilled because the cost or feasibility of making a wired connection is holding the project back. Reconsider the project using industrial wireless technology and you may find that the project becomes an attractive prospect.

Share your connectivity challenges with the experts at Hile Controls of Alabama, combining your own process knowledge and experience with their wireless communications expertise to develop an effective solution.

Friday, July 28, 2017

Basic Checklist for Accurate pH/ORP Measurements

process measurement sensors for pH and ORP
Sensors for pH/ORP measurement
Courtesy Emerson - Rosemount Analytical
The measurement of pH/ORP is a common practice among processors of water. Though the task is ubiquitous, it still remains an analytical process that requires careful execution in order to achieve reliable results.

Emerson contributed an article to wateronline.com, a journal focused on the many aspects and uses of water across all sectors. The article (which can be found here at the publication site) summarizes the basics one needs to approach pH/ORP measurement. All credit for the article goes to the authors at Emerson, and it is shared here to assist our readers in solidifying their skill, accuracy, and understanding of this important measurement.

Share your process measurement challenges of all types with instrumentation specialists, combining your own knowledge and experience with their product application expertise to develop effective solutions.


Monday, July 17, 2017

Foundation Fieldbus – Part Two

storage tanks
Almost any operation can benefit from incorporating
Foundation fieldbus
Since automatic control decisions in FOUNDATION fieldbus are implemented and executed at the field instrument level, the reliance on digital signals (as opposed to analog) allows for a streamlined configuration of direct control system ports. If the central control device were to become overloaded for any reason, tasks related to control decisions could still be implemented by operators in the field. This decentralization of the system places less burden and emphasis on the overall central control unit, to the point where, theoretically, the central control unit could stop functioning and the instrumentation would continue performing process tasks thanks to the increased autonomy. Allowing for the instrumentation to function at such an increased level of operation provides a proverbial safety net for any system related issues, with the capacity for independent functionality serving as both a precaution and an example for how process technology continues to evolve from analog solutions to fully end to end digital instrumentation.

Even in terms of the FOUNDATION compliant instrumentation itself, there were two levels of networks being developed at this increased level of operation, initially: the first, H1, was considered low speed, while H2 was considered high speed. As the design process unfolded, existing Ethernet technology was discovered to fulfill the needs of the high speed framework, meaning the H2 development was stopped since the existing technology would allow for the H1 network to perform to the desired standards. The physical layer of the H1 constitutes, typically, a two-wire twisted pair ungrounded network cable, a 100 ohm (typical) characteristic impedance, DC power being conveyed over the same two wires as digital data, at least a 31.25 kbps data rate, differential voltage signaling with a defined threshold for both maximum and minimum peak receive rates, and Manchester encoding. Optical fiber can be used on some installations in lieu of the twisted pair cable.

Most of these specifications were exactly designed to withstand extremely challenging process control environments while still not abandoning the philosophy of being easy to build and implement, especially in terms of new system establishment. The most crucial aspects of many process control systems are streamlined together, allowing for consistent communication and synchronization. All aspects are viewable from both the legacy central controller and also via each individual device. Despite the data rate of 31.25 kbps being relatively slow, what is sacrificed in terms of speed is more than made up for in terms of the system being compatible with imperfect cables and other hiccups which may destabilize a network with faster speeds. The evolved technology, ease of installation, and durability have made the H1 network a widely used implementation of the FOUNDATION fieldbus technology. The standard is currently considered one of a few widely adopted industrial process control communications protocols.

Foundation Fieldbus Equipped Instrumentation – Part One

Foundation filedbus capable pressure transmitter
Foundation fieldbus capable instruments and devices
provide benefits to process operators
Image courtesy Autrol
Autonomous control and digital instrumentation are two capabilities enabling highly precise or complex execution of process control functions. FOUNDATION fieldbus instrumentation elevates the level of control afforded to digital field instrumentation where, instead of only communicating with each other, instruments involved in particular process control systems can independently facilitate algorithms typically reserved for instruments solely dedicated to controlling other instruments. Fieldbus capable instrumentation has become the standard instrumentation for many process industry installations due to the fact the FOUNDATION design principle streamlines process systems. A large contributor to FOUNDATION’s success has been faster installation as opposed to operational controllers which do not feature the fieldbus configuration. Newer process companies, or process control professionals seeking to establish a new system, have gravitated towards fieldbus due to the combined advantages of system conciseness and ease of implementation.

In a typical digital control system, dedicated controllers communicate with field instrumentation (the HART protocol is a prime example of digital communication at work in the industry). The host system controls configuration of instruments and serves as a central hub where all relevant control decisions are made from a single dedicated controller. Typically, these networks connect controllers and field devices through coupling devices and other ‘buses’ which streamline many different instruments into a complete system.

FOUNDATION fieldbus approaches the same network scheme with an important difference. Whereas in a legacy or more conventional system, either algorithmic or manual decisions would need to be implemented via the dedicated system level controllers, instruments utilizing FOUNDATION fieldbus architecture can execute control algorithms at the local device level. The dedicated controller hub is still present, so that operators can view and monitor the entire network concurrently and make status changes. Algorithmic execution of control functions becomes entirely device reliant thanks to the FOUNDATION protocol. Additionally, even though FOUNDATION implements an advanced configuration, some operators use the capabilities introduced in the fieldbus upgrade to implement specific algorithms via each device while concurrently maintaining algorithms in the central controller. This dual algorithmic configuration allows for several advantages, including the ability for increased system precision.

Since individual devices in the control process are calibrated and able to execute their own control functions, issues in the process with particular devices can be isolated and dealt with in a more specified manner by technicians using the instruments in the field. The central operator retains the capacity to use the control hub to alter and direct the control system.

Saturday, July 8, 2017

In Situ Gas Measurement Instrument for Emission Monitoring and Combustion Control

in situ gas monitor
Model GM 35 in situ gas monitor
Image courtesy of Sick USA
The measurement of gas component concentration, especially in operations involving combustion, is necessary to assure regulatory compliance, as well as levels of fuel consumption efficiency. Measurement instrumentation that is reliable, easy to maintain, and accurate delivers needed information without a substantial burden.

What are some attributes of a gas measurement instrument that may prove useful for industrial installations?

  • Ability to measure multiple constituents, such as CO, CO2, H2O, or N2O with a single instrument. 
  • Built-in capability for zero and span test without the need for test gases.
  • In place continuous operation with real time measurement output, eliminating the need for gas sampling or transport. Measurement is accomplished in the process flow.
  • Measurement of temperature and pressure included in unit function.
  • Model available in cross duct and single ended probe type versions.
  • Rugged, properly rated, enclosures for installation outdoors in challenging industrial environments
Each installation scenario will have its own challenges, and each process its own set of measurement requirements. Share your application specifics with a process measurement specialist, combining your own knowledge and experience with their instrument application expertise to develop an effective solution.