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

Product Options Round Out Fulfillment of Application Requirements





Analynk Wireless, in addition to their standard products, can provide an extensive range of value added services to help customers quickly and effectively fulfill project requirements involving wireless communications and process control. Share your challenges with the wireless and process control experts at Analynk, combining your process knowledge with their wireless and control expertise to develop effective solutions.

Analynk's Telmar Brand of Process Control Products

enclosed industrial process controller
Telmar enclosed 2-wire transmitter
Analynk Wireless, in addition to wireless process signal transmitters, receivers, and repeaters, manufactures a broad line of industrial process control products under the Telmar brand.

  • 2-Wire Transmitters with AC, DC, mA, slidewire, RTD, or tachometer inputs. General purpose enclosure is standard, with options for others to meet any rated environment.
  • 4-Wire Transmitters with dozens of combinations of input and output signals. Alarm outputs available as option.
  •  Signal Alarms that accommodate inputs from thermocouple, DC current, DC voltage, RTD, AC voltage, AC current, tachometer, slidewire, or strain gauge.
  • Pneumatic Transmitters for pressure to current, current to pressure, pressure to voltage, and voltage to pressure applications.
  • Tachometer Transmitters
  • Explosion Proof Transmitters with or without local indicator for thermocouple or RTD input.
    • industrial process transmitter RTD with explosion proof enclosure and display
      RTD transmitter with explosion proof enclosure and display
  • Indicators and Meters with general purpose or explosion proof enclosures in loop powered or external powered versions.
  • Sensor Assemblies for general, corrosive, or explosion proof applications. Thermocouple or RTD.
The Telmar brand provides complementary products for wired process control applications, or can be supplemented by Analynk's wireless products to provide wireless connectivity between point of measurement and point of control.

Reach out to Analynk with your process control challenges, combining your process knowledge with their product expertise to develop effective solutions.

Battery Powered Transmitter for Industrial Wireless Communication

battery powered wireless transmitter in explosion proof enclosure for industrial process control
Battery powered wireless process signal transmitter
in explosion proof enclosure
Industrial settings can present difficult or unique challenges to automation and control designers. Each new challenge seems to be met with a new, improved, or adapted product which fulfills the requirements.

Analynk's standard array of wireless transmitters operate on 24 Vdc. For installations without any appropriate power source, three models are configured to operate on power provided by batteries. The A753-BT transmitters operate on battery power, utilizing a real time clock to schedule transmission intervals appropriate for the application. The transmitter also provides an excitation voltage for external devices. Your sensor's 4-20 mA output provides input to the Analynk transmitter, along with two discrete switches. The transmitter communicates with all of Analynk's receivers.

The unit pictured is configured for use in a hazardous area, with explosion proof enclosure. Other models are suitable for DIN rail mounting in an enclosure of your selection, or provided preconfigured in a NEMA 4 enclosure.

Share your wireless process control connectivity challenges with the experts at Analynk.



Explosion Proof Antennas For Wireless Communications in Hazardous Industrial Settings

explosion proof antenna for industrial wifi wireless communications
CTX Series Explosion Proof Antenna
Analynk
Wireless connections between process measuring and control devices brings several benefits to an industrial operation. The signal cable free installation saves valuable time and space, reduces damage exposure, and simplifies process equipment layout modifications.

Implementing wireless communications in hazardous areas, whether through WiFi or other radio frequency channels, poses a unique set of challenges to successful implementation. Points of network access and other transmission and receiving equipment will require a level of isolation and hardening appropriate for the hazardous industrial environment. Specialized explosion proof enclosures can house the needed equipment, but antennas must extend outside these metal enclosures and into the hazardous environment in order to transmit and receive process signals. This imposes rigorous requirements on antenna design and construction.

Analynk Wireless manufactures patented UL listed hazardous area explosion proof antennas for industrial installations.  Their CTX and CTM series antennas carry an array of third party approvals and are suitable for use in a broad range of hazardous environments. Models can accommodate WiFi and other RF communications across frequency bands commonly utilized in industrial settings, as well as cellular and satellite communications.

Data sheets for the CTX and CTM Series antennas are included below for more detail. Share your wireless communication challenges and application questions with the experts at Analynk and work together to produce the best solutions.

Analynk Custom Design Services

analynk wireless company logo
Analynk Wireless, in addition to their line of wireless communication products for process monitoring and control, offers custom design services for a broad range of applications in the industrial control arena.

The same engineering and design expertise that goes into every Analynk product can be channeled into specialty products or assemblies for your applications. Whether something as simple as a custom adapter board to facilitate connection between some dissimilar components or an embedded controller with a customized user interface, no application is without a solution.
  • Concept
  • Schematic design
  • PCB design
  • Firmware
  • Prototyping
  • Production
Share your ideas with the design team at Analynk. Combine your expertise with theirs to develop an effective solution.

Signal Alarms for Process and Operations Monitoring

process control analog signal alarm Telmar Analynk
Telmar 500 Series Signal Alarm
Analynk
Signal alarms provide functionality related to a monitored process condition, which serves as the input to the device. High, low, or both high and low alarm points can be set on the device. When the process condition reaches one of the setpoints, a relay changes state. The relay, rated at 5.0 amperes at 120 VAC, can be used to annunciate the alarm occurrence or activate another device to take some other appropriate action. A number of input options are available that accommodate a broad range of process applications.

  • Thermocouple
  • Millivolt DC
  • RTD
  • AC or DC Current
  • Slide Wire
  • Strain Gauge
  • Tachometer
  • AC or DC Voltage
The standalone signal alarms can be incorporated into new control installations, or added to existing control systems to expand functionality. More information can be found in the data sheet included below, or reach out to Analynk and share your signal or process monitoring challenges and requirements.




New Hazardous Area Wireless Access Point Enclosures

Wireless Access point enclosure for hazardous area
Model AP 412 Hazardous Area Access Point Enclosure
Analynk Wireless has added two new entries to their line of wireless access point enclosures for use in hazardous areas. Each access point enclosure is shipped ready for installation of your access point device, with hazardous area antennas, cables, mounting bracket, and antenna cables included.

Analynk access point enclosures are preconfigured to house a specific manufacturer and model number access point. Review the product offering and see the long list of accommodated access points. If you want to use an access point not shown on the list, contact Analynk for a solution.

The new models are designed to house the Cisco 2802E and 3802E Dual Band Access Points. Data sheets for both are included below.

Analynk manufactures a diverse array of equipment utilized in establishing wireless connections between industrial process control devices. Share your wireless connectivity challenges with the experts at Analynk and get effective solutions.




Piping & Instrumentation Diagrams in Process Control

electric power plant
All processes benefit from P&ID
P&ID's (Piping & Instrumentation Diagrams), or Process and Control Flow Diagrams, are schematic representations of a process control system, used to illustrate the piping system, process flow, installed equipment, instrumentation, and functional relationships among all the system components.

Intended to provide a comprehensive picture of all piping and associated hardware, including physical branches, valves, equipment, instrumentation and interlocks, the P&ID employs a set of standard symbols representing each component of the system such as instruments, piping, motors, pumps, etc. The use of standard symbols provides a universal depiction that can be read and understood by operators, technicians, outside contractors, and other similarly trained individuals.

P&ID’s can be very detailed and are generally the primary source from where instrument and equipment lists are generated, also being a very handy reference for maintenance and upgrades. P&ID’s also play an important early role in safety planning by enabling an understanding of the operating states and relationships of all components in the system.


Know Analynk Wireless - Introductory Video



Analynk Wireless is an innovative designer and supplier of wireless instrumentation for the process control industry. Instruments and equipment have been successfully implemented in numerous applications including temperature measurements, 4-20 mA bridges, discrete inputs/outputs, pulse inputs, lighting and pump controls. The company's products are used in both hazardous and non-hazardous locations. Analynk Wireless also manufactures a line of traditional wired process measurement and control instrumentation under the brand name Telmar Instruments.

Share your wireless connectivity challenges with the experts at Analynk. Combining your process knowledge with their expertise with produce effective solutions.

Comparison of 2.4 GHz and 900 MHz for Industrial Process Control Wireless Connection

logo for Analynk Wireless LLC
Wireless transmission of measurement and control signals are the future, and present, of process control. WiFi is already prevalent in higher density environments and providing benefits of reduced cabling and more. Wireless communications also can be used to connect devices over substantial distances, even globally. This article will focus on applications of moderate to long distance that will employ point to point communications of dedicated devices. Here is an illustrated example, with level measurement instruments on storage tanks located remotely from a data monitoring station.

storage tanks with level gauges wireless transmission to data monitoring and control station
Example of wireless connection between remote tanks and data collection and control center
In establishing a wireless process signal connection between the two points in the example, an initial consideration will be whether to employ 900 MHz or 2.4 GHz as the radio band. There are some general implications associated with the selection.

  • Signal attenuation over any distance is greater for 2.4 GHz than 900 MHz. This generally means that 900 MHz can cover a greater distance and provide a signal of sufficient strength to properly communicate.
  • Atmospheric attenuation for either frequency band is about the same, with a very slight advantage to 900 MHz.
  • Both frequencies require "line-of-sight" to provide predictable and reliable operation. Obstructions within that zone can degrade the signal. Any obstructions with dimensions approximating the wavelength of the signal tend to have a greater impact. The wavelength of a 2.4 GHz signal is 12.5 cm (4.52 inches), 900 MHz is 33.3 cm (84.6 inches). 2.4 GHz signals are susceptible to interference by smaller objects in the transmission path than are 900 MHz signals.
  • Without getting too technical, the height of a 900 MHz antenna will need to elevated to a greater distance the that of a 2.4 GHz antenna in order to provide what is known as "free space propagation". This is related to the Fresnel Zone and has greater impact as transmission distance increases.
  • FCC rules allow larger transmit power ratings for 2.4 GHz radio signals than 900 MHz, increasing the potential range for 2.4 GHz.
Evaluate your potential installations with the above points in mind. Their impact on any particular application can vary depending upon the distance, topography, and potential obstructions. Share your wireless communications challenges with the experts at Analynk Wireless. Combining your site and process knowledge with their product application expertise will produce an effective solution.

Analynk Extends Offering of Hazardous Area Access Point Enclosures

explosion proof enclosure for wireless network access point
AP411 for the Meraki MR72 Wireless Access Point
is Analynk's latest addition to the product line
Analynk Wireless manufactures equipment for transmitting process control signals via WiFi, radio, satellite, and cellular networks. One of their continuously expanding product lines is the Hazalynk series of explosion proof access point enclosures for installing wireless access points in hazardous areas.

The company currently has specific models designed for simple accommodation of wireless access points from Symbol, Cisco, Meru, Meraki, Aruba, HP, and Motorola. Each model is specifically configured to house a particular model wireless access point. Antenna openings, cables, and internal mounting bracket are all coordinated to provide easy installation of the wireless access point. Explosion proof antennas suitable for the access point are included with each enclosure.

The latest addition to the product line is intended for use with the Meraki MR72 Access Point. A data sheet for the unit is included below, or you can contact Analynk for more information about this or any of their other industrial wireless products.



Wireless Communications for Industrial Automation Continues to Expand Because It Performs

communications satellite in Earth orbit
Wireless communications capabilities for process control
extend beyond WiFi
Wireless connection between a sensor and control or monitoring station is not new anymore. Products have matured, familiarity with the technology is widespread. Certainly, there are still large swaths of industrial installations that do not utilize the technology. This can be for any number or reasons, but new industrial technology tends to follow a predictable course throughout its adoption. There will be innovators and early adopters that can justify higher risks with the prospect of great returns. Many industries and companies will wait until perceived technological difficulties with implementation are overcome and products become more mainstream and easy to apply. That is where industrial wireless is today. Assembling complete working systems is a straight forward operation. Costs are comparatively modest. It's easier to visualize a payback.

Let's review some of the benefits a wireless installation can bring.

  • 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.
Analynk Wireless manufactures a broad range of wireless communications equipment for industrial process control and automation. Share your wireless connection challenges and ideas with the experts at Analynk and start benefiting from the technology. It's not new anymore. It's mainstream.


Transmitting Multiple I/O Points Along A Single Signal Path

Industrial wireless 900 MHz or 2.4 GHz multiple I/O transmitter/receiver
Analynk A16000 Expansion Module provides up to
16 I/O points for wireless transmission or reception.
Wireless transmission of process control signals is steadily increasing in prevalence throughout many industrial environments. The ease of implementation, with no long cable runs to plan, layout, install, protect, and maintain, allows wireless installations to fulfill application niches that may have been considered impractical in the past.

Analynk provides hardware that easily allows the transmission and reception of up to 16 I/O points using a single transmitter and receiver. The A16000 Expansion Module can be configured with up to four internal cards that accommodate various types of input and output signals. The process is similar to setting up the I/O on a PLC. Connect the process signals to the A16000, and the A16000 to one of Analynk's transmitter or receiver devices. Setup is straight forward and allows the installation to be operable in minimal time.

Share your wireless communications and signal transmission challenges with the experts at Analynk and get recommendations on how to best implement workable solutions.


Understanding Telecommunications Terminology

satellite orbiting earth for industrial process control wireless communications
Industrial wireless communications can include satellites
If you are delving into wireless communications for process control operations and expect to go beyond the use of industrial Wi-Fi, you are likely to encounter some concepts and lexicon that may be unfamiliar. A source of recognized standard definitions for industry specific terms will serve as a useful tool for understanding the specifics of radio communications.

Federal Standard 1037C, entitled Telecommunications: Glossary of Telecommunication Terms was issued by the General Services Administration late in the last century. It was superseded in 2001 by American National Standard T1.523-2001, Telecom Glossary 2000, published by Alliance for Telecommunications Industry Solutions commonly known as ATIS). The current version of the ATIS Telecom Glossary is available for use by the public. Find the glossary website, with its search engine, and either type a term to search for in the box or browse the extensive listings in alphabetical order. It's easy to use and can help you sort out the meanings of some industry specific terms.

Analynk Wireless is a wireless communications equipment provider to the industrial process control sector. Contact the application specialists at Analynk and share your wireless communication challenges.

glossary of telecommunications terms
Screen shot of the glossary, showing search box in upper left area









Understand Fresnel Zones and Their Potential Impact On Your Process Signal Radio Transmission

wire frame rendition of ellipsoid representing Fresnel zone in radio transmission
Rendition of an ellipsoid, the representative shape
of a Fresnel zone
Most of us have been touched by wireless communications in the industrial process control setting. The majority of the installations are likely to be networks that operate similarly to the wireless network you may have in your home. Multiple points communicate through a network controller of some sort. The facility is flooded with signal coverage through multiple access points, so there may not be much need to consider signal propagation. Of course, this is an oversimplification. The point to be made is that, as an operator or implementer, making the actual signal connection is probably not going to be an issue in most cases.
How would you approach an application with a one mile transmission distance?
antennas and associated Fresnel zones and obstruction avoidance
Antennas with three Fresnel zones depicted and
obstruction that is outside the primary Fresnel zone
Courtesy Wikipedia
An extended transmission distance across an outdoor area requires more understanding of signal propagation and the factors that can impede the successful delivery of your
process data from transmitter to receiver. One concept that may come into play is the Fresnel zone.

I shall avoid any deep or technical approach to Fresnel zones, as my purpose is to provide the designer, technician, or implementer, who may have limited radio expertise, familiarity with the subject at a level empowering visualization of the concept to recognize the potential for its impact upon achieving a successful project. That said, a Fresnel zone, of which there an infinite theoretical number, is an ellipsoid shaped area extending between transmission and receiving antennas.  While we often consider the transmission path between two points as the popular "line of sight", an unobstructed straight line, radio frequency transmission is more accurately characterized by Fresnel zones. Being aware of the shape of the first, or primary, Fresnel zone for your application is an important element in identifying potential obstructions. A general practice is to keep the primary Fresnel zone at least 60% clear of signal obstructions, in order to maintain high wireless link performance.

There are numerous sources of Fresnel zone calculators online, but a strong recommendation to consult with your selected wireless equipment provider is in order here. Combine their expertise at applying their products with your application knowledge to reach the best outcome.

Understand Petroleum Refining for Better Process Control Support

Oil refinery petroleum refinery
Oil refineries can have different specialties and function
The petroleum refining industry provides an expansive market for process measurement and control instrumentation and equipment, valves, and process analyzers. Having a basic understanding of the industry can help purveyors of instrumentation and equipment properly address customer needs, as well as recognize where opportunities may lie. Here is a summary of the types of plants and processes.

Petroleum refineries produce liquefied petroleum gases (LPG), motor gasoline, jet fuels, kerosene, distillate fuel oils, residual fuel oils, lubricants, asphalt (bitumen), and other products through distillation of crude oil or through re-distillation, cracking, or reforming of unfinished petroleum derivatives.

There are three basic types of refineries:
  • Topping refineries
  • Hydroskimming refineries
  • Upgrading refineries (also referred to as “conversion” or “complex” refineries). 
Topping refineries have a crude distillation column and produce naphtha and other intermediate products, but not gasoline. There are only a few topping refineries in the U.S., predominately in Alaska.

Hydroskimming refineries have mild conversion units such as hydrotreating units and/or reforming units to produce finished gasoline products, but they do not upgrade heavier components of the crude oil that exit near the bottom of the crude distillation column. Some topping/hydroskimming refineries specialize in processing heavy crude oils to produce asphalt.

The vast majority (75 to 80 percent) of the approximately 150 domestic US refineries are upgrading/conversion refineries. Upgrading/conversion refineries have cracking or coking operations to convert long-chain, high molecular weight hydrocarbons (“heavy distillates”) into smaller hydrocarbons that can be used to produce gasoline product (“light distillates”) and other higher value products and petrochemical feedstocks.

Figure 1 provides a simplified flow diagram of a typical refinery. The flow of intermediates between the processes will vary by refinery, and depends on the structure of the refinery, type of crude processes, as well as product mix.

Figure 1 - Refinery Flow Diagram
Wikipedia - www.en.wikipedia.org/wiki/Petroleum_refining_processes
The first process unit in nearly all refineries is the crude oil or “atmospheric” distillation unit. Different conversion processes are available using thermal or catalytic processes, e.g., delayed coking, catalytic cracking, or catalytic reforming, to produce the desired mix of products from the crude oil. The products may be treated to upgrade the product quality (e.g., sulfur removal using a hydrotreater).

Side processes that are used to condition inputs or produce hydrogen or by-products include crude conditioning (e.g., desalting), hydrogen production, power and steam production, and asphalt production. Lubricants and other specialized products may be produced at special locations.

Temperature Measurement: Thermistors, Thermocouples, and RTDs

This post explains the basic operation of the three most common temperature sensing elements - thermocouples, RTD's and thermistors.

A thermocouple is a temperature sensor that produces a micro-voltage from a phenomena called the Seebeck Effect. In simple terms, when the junction of two different (dissimilar) metals varies in temperature from a second junction (called the reference junction), a voltage is produced. When the reference junction temperature is known and maintained, the voltage produced by the sensing junction can be measured and directly applied to the change in the sensing junctions' temperature.

Thermocouples are widely used for industrial and commercial temperate control because they are inexpensive, sufficiently accurate for many uses, have a nearly linear temperature-to-signal output curve, come in many “types” (different metal alloys) for many different temperature ranges, and are easily interchangeable. They require no external power to work and can be used in continuous temperature measurement applications from -185 Deg. Celsius (Type T) up to 1700 Deg. Celsius (Type B).

Common application for thermocouples are industrial processes, the plastics industry, kilns, boilers, steel making, power generation, gas turbine exhaust and diesel engines, They also have many consumer uses such as temperature sensors in thermostats and flame sensors, and for consumer cooking and heating equipment.
wire wound RTD
Coil wound RTD element
(image courtesy of Wikipedia)

RTD’s (resistance temperature detectors), are temperature sensors that measure a change in resistance as the temperature of the RTD element changes. They are normally designed as a fine wire coiled around a bobbin (made of glass or ceramic), and inserted into a protective sheath. The can also be manufactured as a thin-film element with the pure metal deposited on a ceramic base much like a circuit on a circuit board. 

thin film rtd
Thin-film RTD element
(image courtesy of Wikipedia)
The RTD wire is usually a pure metal such as platinum, nickel or copper because these metals have a predictable change in resistance as the temperature changes. RTD’s offer considerably higher accuracy and repeatability than thermocouples and can be used up to 600 Deg. Celsius. They are most often used in biomedical applications, semiconductor processing and industrial applications where accuracy is important. Because they are made of pure metals, they tend to more costly than thermocouples. RTD’s do need to be supplied an excitation voltage from the control circuitry as well. 

The third most common temperature sensor is the thermistor. A thermistor functions similarly to a RTD in that it exhibits a change in resistance associated with a change in temperature. A difference between the two is that, instead of using pure metal, thermistors use a very inexpensive polymer or ceramic material as the resistance element. The practical application difference between thermistors and RTD’s is the shape of the resistance curve for the devices. The RTD is linear, whereas a thermistor is non-linear, making it useful only over a narrow temperature range. 

thermistor
Thermistor bead with wires
(image courtesy of Wikipedia)
Thermistors however are very inexpensive and have a very fast response. They also come in two varieties, positive temperature coefficient (PTC - resistance increases with increasing temperature), and negative temperature coefficient (NTC - resistance decreases with increasing temperature). Thermistors are used widely in monitoring temperature of circuit boards, digital thermostats, food processing, and consumer appliances.

Developing a Useful Alarm Strategy

stainless steel tanks pharmaceutical production facility process control
Industrial process at pharmaceutical plant
Industrial process control operators and designers have the capability to measure many aspects of machine operation and process performance. Determining the elements to measure, method of measurement, and how to handle and process the derived information can be challenging, but can also impact the security, performance, and safety of an operation. A plan for monitoring, reporting, and responding to abnormal process conditions, if properly developed and executed, can yield real benefits to a process operator. A protocol that is not well conceived may produce a negative operational impact by creating events that unnecessarily draw resources away from productive endeavor. That protocol, or plan, is often referred to as an alarm plan.

There are numerous forces that can influence the development and implementation of an alarm plan. Each operation must incorporate its own set of external regulatory requirements, internal procedures and policies into a complete alarm protocol. Distilling that macro description down to a workable set of procedures and response tasks is where the real work begins. There is, however, a basic framework that can help organize your thinking and focus on what is most important.

  • What parameters define the process or operation?
    Produce a schedule of every non-human element that is required to make the process function. This will require drilling down through every machine and material that is part of the operation. Expect the schedule to be extensive, even huge. If it is not, consider that your analysis may not be reaching deep enough. The goal here is to create an overview of what makes the process work and provide a tool for systematically studying the process elements and gleaning possible commonalities or relationships among them. Consider disregarding things that cannot be measured, since that prevents the derivation of data for evaluation. Review the completed schedule and decide which parameters shall be measured and evaluated for proper performance.
  • What level of measurement is needed for each monitored parameter?
    An assessment of the needed accuracy, frequency, and resolution for parameter measurement will help define the requirements for instrumentation or other devices used to monitor a particular item. The goal is to make sure the monitoring device is capable of detecting and delivering information of sufficient quality to make decisions.
  • Define the limits of acceptability for each monitored parameter.
    Until the endpoint of the process or operation, each step is likely dependent in some way on previous steps. The output of each step becomes the input of the next. While this, in many cases, may be an oversimplification, it is important to consider the relationships between the
    industrial control automated filling line process automation
    High speed filling operation
    tasks and operations that comprise the process. Monitored parameters should relate to the successful completion of a process step, though not necessarily be a direct indicator of success. The maintenance of the parameter within certain bounds may be used as an indicator that a component of successful completion was properly attained. Defining limits of acceptability may involve an element of subjectivity and will likely be customized to accommodate the process. Each organization shall evaluate their operation and determine limits based upon intimate process knowledge and experience.
  • Define abnormal operation for each monitored parameter.
    Abnormal operation may not necessarily be any value not within what is considered acceptable. Consider abnormal to be the range of values that would be cause for notification of the operator, or even automated or human intervention. Note that the definition of unacceptable or abnormal operation might appropriately include filters or defined relationships with other parameters. An example of a simple filter is a time delay. If the measured variable exceeds the specified limit for 2 seconds, it make not be significant. If the threshold is exceeded for 2 minutes, it may be cause to take action. As with the limits of acceptability, developing the definition of abnormal operation for each parameter will be customized for each process.
  • Provide a defined response for every alarm occurrence.
    If it is important to monitor something, then it is likely important to do something when things get out of hand. Human executed alarm response should be concise and uncomplicated, to reduce the probability of error. Automated response should be designed in a manner that provides for functional testing on a regular basis. The scope of the response will be specific for each process, with the level of response depending upon factors determined by the process operators. Response can be as simple as annunciating the condition at a monitoring station, or as dire as shutting down part or all of the process operation.
  • Review every alarm occurrence
    Each alarm event should be logged and reviewed. Consider whether the event detection and response was adequate and beneficial. If the results were less than expected or desired, assess whether changes can be made to provide improved results in the future. The alarm plan is unlikely to be perfect in its first incarnation. Be prepared to reevaluate and make changes to improve performance.
The exercise of developing a comprehensive alarm plan will help to build understanding of process operation for all involved parties. This article is but a brief synopsis of the subject, intended to get the reader on the path of developing a useful alarm plan. Your alarm plan should an extension of process operation decision making, and have a goal of enhancing safety and reducing loss.   


Learn From History - Explosion at Texas Facility

Industrial accidents range in severity and impact from minuscule to catastrophic. As operators, owners, or technicians involved with industrial operations, we all have a degree of moral, ethical, and legal responsibility to conduct our work in a manner that does not unduly endanger personnel, property, or the environment. Maintaining a diligent safety stance can be helped by reviewing industrial accidents at other facilities. There is much to learn from these unfortunate events, even when they happen in an industry that may seem somewhat removed from your own.

The U.S. Chemical Safety Board, or CSB, is an independent federal agency that investigates industrial chemical accidents. Below, find one of their video reenactments of an explosion that occurred in Texas in 2013, along with their findings regarding the cause of the incident. Check out the video and sharpen your senses to evaluate potential trouble spots in your own operation.

Contact Analynk for any safety related information you may need concerning their products.