Chloride & Sulfate Process Analyzer

Determining the levels of chloride and sulfate in water is especially useful to power plant operators. Contamination of the power plant process water by chloride and sulfate leads to corrosion, pitting, and stress corrosion cracking in pressurized equipment and piping. The deposits that can result from contamination reduce heat transfer efficiency. Boilers and turbines suffer under the effects of excessive chloride and sulfate levels, so monitoring of their levels at critical locations in the steam system provides operators with actionable information that can be used to maintain efficiency and reduce maintenance demand.

Mettler Toledo, under their Thornton brand, provides a reliable and affordable analyzer for chloride and sulfate concentration in water. The video included with this post outlines the operational advantages of microfluidic capillary electrophoresis, the measuring technology employed in their system.

Share your on-line process analysis challenges with product application specialists, combining your own process knowledge and experience with their product application expertise to develop and effective solution.

Complete Bioreactor Package for Streamlining Bioprocess Applications

Complete Bioreactor Systems 2 to 20 Liters
Courtesy ILS Automation

Planning, purchasing, and configuring a bioreactor and an associated control system can be a time consuming project that taxes the limits of your technical knowledge. Coordinating the connectivity of all the components and getting everything to work in harmony takes time away from devotion to the mission goals of your project or organization.

ILS Automation, experts at bioreactor process control, now offer fully packaged and integrated complete bioreactor systems that allow customers to get up and running with a minimized time commitment. The new packaged systems include reactor vessels from 2L to 20L and combine useful design principles into every unit.

• Non-proprietary components that are readily available.
• Design empowers customer, or a third party, to perform service.
• Software and interfaces match customer requirements.
• Complete documentation and source code provided.
• Ongoing support and technology upgrades made available

More detail is provided in the datasheet included below. Share your bioprocessing and analytical requirements and challenges with application experts. Combine your own process knowledge and experience with their product application expertise to develop effective solutions.

Complete Bioreactor Package for Streamlining Bioprocess Applications from Alliance Technical Sales, Inc.

Sensor Mount Transmitter Delivers New Functionality to Smart Sensors

The new M100 Sensor Mount Transmitter affixes directly
to ISM type sensors.

Smart sensors for pH, DO, and CO2 deliver a high level of performance and productivity enhancement for analytical users. Reduction in the time needed for sensor maintenance and calibration channel more time into delivering analytical results.

The new M100 SM (Sensor Mount) transmitter from Mettler Toledo streamlines the integration of their ISM smart sensors into bioprocess control systems. The transmitter mounts directly to the sensor, without the need for separately housed electronics. The compact configuration combines the advantages of the ISM smart sensor with several analog and digital outputs for connection to bioprocess controllers.

The M100 SM is available for use with  a variety of Mettler Toledo ISM sensors, including those for pH, DO, and CO2. The transmitters provide two 4-20 mA outputs and one digital Modbus RTU connection. Configuration and sensor status check can be accomplished via Bluetooth using a desktop PC or mobile device.

More detail is provided below. Share all your analytical challenges with application specialists, combining your own process knowledge and experience with their product application expertise to develop effective solutions.

Sensor Mount Transmitters For Smart Sensors from Alliance Technical Sales, Inc.

Properly Applying Flexible Heat Tape

Heat tape, with its flexibility, provides a good means of delivering heat to a wide range of process applications. It can be applied to pipes, vessels, or other objects that need to be heated for any number of reasons. The range of available product materials and watt densities assures that there is a heat tape configuration for almost every application. This video shows how to properly apply and install heat tape to get the best performance and maintain safe operating conditions.

Share your process heating requirements of all types with an industrial heating specialist, combining your process knowledge and experience with their product application expertise to develop effective solutions.

Expanded Tunable Diode Laser Parameter and Installation Range

The GPro 500 Series TDL Gas Analyzers
Courtesy Mettler Toledo

Inline continuous gas analysis is a necessary tool for effectively tracking emissions of many types. A tunable diode laser (TDL) can provide accurate continuous measurement of target gas concentration. With the proper installation configuration, the instruments exhibit no drift and are not subject to interference, offering a sustainable means of delivering needed process data.

Mettler Toledo, with the expansion of their GPro 500 Series of TDL instruments, now provides continuous gas concentration measurement solutions for carbon dioxide, carbon monoxide, oxygen, moisture, hydrogen sulfide, and hydrogen chloride.

Varying application conditions can present specific challenges to an effective installation of a TDL, so the GPro 500 is available in variants that accommodate a range of installation conditions.

• The standard probe is a purged configuration for general use.
• A non-purged version is suitable for reactor of other vessel installation.
• Combustion process measurements are handled by the non-purged filter probe, with a sintered filter to prevent dust from entering the measurement cell.
• High particulate combustion processes can be served by the filtered probe provided with a blow-back port. It allows high pressure instrument air to clean the filter.
• A wafer version, for tight spaces and pipes, is also available.
• Two adaptions are also available for use with existing sample conditioning equipment.
• A retroflector adapter enables a cross-pipe measurement. It is designed to forgo the need for alignment, making installation simple.

Tunable diode laser gas analyzers provide an effective means of continuous gas concentration measurement for the process industries and combustion operations. Share your process and combustion gas analysis challenges with a product application specialist, combining your own valuable process knowledge and experience with their product application expertise to develop effective solutions.

Silicone Rubber Heating Blankets - Special Delivery for Industrial Heating Applications

Silicone Rubber Heating Blanket
One of countless shapes and sizes
Courtesy Briskheat

Electric heaters for industrial and commercial applications are available in an almost dizzying range of types, materials, and forms. One of those is the silicone rubber heater.

Stock shapes and sizes are available from many manufacturers, but one distinct advantage of silicone rubber heaters is their flexibility. The resistance heater wires are encased in a silicone rubber sheet, providing the ability to wrap the assembly around an object or manipulate it into a close fit with the target of a heating application. The silicone rubber encasement also provides a high level of protection for the heater wires from impact, moisture, and some chemicals.

The watt density of the heaters can be specified to provide a good match between the delivery of heat and the need for it. Custom shapes and configurations can be manufactured to order, and on board or remote controllers provided. Pressure sensitive adhesive is a common option that facilitates the installation of the heater assembly to a part or vessel.

The maximum application temperature is in the range of +450°F (+232°). These heaters are a useful selection option for a large range of operations demanding heat to be applied directly to a surface, object, tank, drum, or other vessel. Share your industrial heating requirements with product specialists for the best match up between heater technology and your application.

Humidity Measurement - Technical Details

Industrial humidity measurement instrument
Courtesy Vaisala

Regardless of what industry you may be operating within, humidity, the moisture content of the air surrounding your work, has some degree of impact. Though that impact may be small enough to currently be ignored, building a basic understanding of the relationship of moisture and dry air, how humidity is measured, and how it can impact your operations will make you a more effective and valuable operator of whatever your process might be.

Vaisala, a leader in humidity measurement, has produced a resource in the form of an eBook that breaks down into understandable units various aspects of humidity measurement and the impact of humidity on industrial applications. The eBook contains a basic level of detail, plus provides links to more technical in-depth source material.

Everyone should find something of value in the eBook. Share your humidity questions, concerns, and challenges with product application specialists for assistance and cooperation in developing effective solutions.

Humidity Measurement Handbook for Manufacturing from Alliance Technical Sales, Inc.

Alliance Technical Sales Adds Industrial Process Heating

Array of industrial heating products
Courtesy Briskheat

Alliance Technical Sales recently reached a new representation agreement with BriskHeat Corporation. The industrial heating products and systems manufactured by BriskHeat expand and complement the Alliance product and capabilities offering.

BriskHeat manufactures a broad line of heaters, insulators, and controls for almost every industrial application.

• Cloth Heating Jackets and Insulators
• Heating Tapes
• Heating Cable
• Laboratory Heaters and Equipment
• Etched Foil Heaters
• Silicone Rubber Heaters
• Drum Heaters
• Tote Tank / IBC Heaters
• Gas Cylinder Warmers
• Enclosure Heaters
• Hopper Heating Systems
• Personal Comfort Heating Solutions
• Hazardous-Area Heaters
• Plastic Bending Heaters
• Resistance Wire
• Temperature Controllers
• Temperature Controllers for Outdoor Use
• Insulators
• Heaters and Controls with Canadian Approvals
• Composite Curing Solutions

Share your industrial and process heating requirements with the product specialists at Alliance Technical Sales. Combining your process expertise with their product knowledge will produce effective solutions.

Software For Bioreactors and Batch Processing Pulls Everything Together in One Place

Bioreactors and other batch operations can require the integration and coordinated operation of multiple control loops, data collection and processing, and the equipment and instruments sourced from differing manufacturers. Operations such as these can benefit greatly from productivity improvement afforded by expert level software that automates and coordinates the tasks involved in batch processing.

ILS Automation, a leader and specialist in software and hardware targeted at the automation of batch processing, provides their Batch Expert+ software which allows operators to maximize productivity throughout the entire process. The company takes an open non-proprietary approach to providing solutions for complex batch processing. In the company's own words (from the ILS website) Batch Expert+ software offers:

• Adaptable: Customers can customize a system to meet their needs both now and in the future. Software features are often added to meet the ever-changing needs of process development or the introduction and integration of new measurement technology. 
• IoT Approach: We apply the notion of the Internet of Things (IoT) to laboratory automation. Our controllers integrate smart control elements and instruments in smart ways. Often this implies a digital interface to read and write actual numbers instead of an analog 4-20 mA approximation. Richer and more accurate/precise data is presented for data analysis and automation. Be it gas flow controllers (Alicat and Brooks), digital probes (Mettler ISM, Hamilton Visiferm), scales (Mettler, Sartorius, OHAUS, etc.), cell density (Hamilton Incyte, ABER, Fogale), the IoT approach provides smarter solutions.
• Open: ILS first-and-foremost provides solutions — not just a piece of equipment that is unpacked from a box. To achieve this goal, we don’t hide behind proprietary equipment or software that is rigid and would conform to our thoughts of what our customers need. Our platforms grow and scale to adapt to customer needs through an open software and hardware system based on industrial grade, off-the-shelf components.
• Remote Support: ILS often supports our customers through a remote VPN connection (LogMeIn, Citrix Receiver, etc.). Our customers claim that we have an obsession with bioreactor control and performance tuning. Combining our AFC controller with our BE+ platform, the slightest DO oscillation or anomaly spurs our interest. Through this interaction and customer feedback, we continually learn and improve our products and solutions. Also, we are often not on-site when questions and issues arise just before a 5:00 pm Friday inoculation, so any automation to help the end users is greatly appreciated.

There is more to learn about Batch Expert+ and how it can be incorporated into your own operations. Share your processing challenges with a product specialist, combining your process knowledge with their product application expertise to develop an effective solution.

Batch Expert+ Boosts Lab Productivity from Alliance Technical Sales, Inc.

New Sensor For Measuring Total Chlorine

Zirkon® DIS Total - Total chlorine process sensor

Courtesy Kuntze Instrument

The measurement of chlorine is a mainstay of many disinfection and drinking water treatment processes. Higher levels of accuracy in measurement of chlorine increase the surety of the disinfection process while limiting use of disinfection chemical products to only what is necessary.

Kuntze Instruments has developed and recently released a total chlorine sensor for use in disinfection processing and drinking water production. The Zirkon® DIS Total measures the level of chlorine compounds. Its open and potentiostatic design offers four primary operator benefits.

• Immunity to air bubbles
• Absence of delicate plastic membranes
• No exchange of electrolyte
• No membrane exchange

A data sheet is included below that provides more technical data for the  Zirkon® DIS Total sensor. The sensor is designed and configured in a manner that allows its usage with the full range of applicable instrumentation from the company. 

Share you process analytical and measurement challenges with experts in the application of instrumentation to process measurement. The combination of your process knowledge and their instrument application expertise will produce an effective solution.

Zirkon® DIS Total - Total chlorine process sensor from Alliance Technical Sales, Inc.

Create a Customized On/Off Process Control Unit

In control theory, an on/off controller is a feedback controller that switches abruptly between two states. It is often used as a control method for a process which can tolerate ongoing change in the process value within a band, referred to as the hysteresis. A common example of an on/off temperature control operation is a residential thermostat. They control the temperature of your home, turning off the heating or cooling system at your comfort setting, waiting for some significant change to occur, then turning on again to eliminate that difference. The process cycles continually. Many process operations can utilize simple on/off control action to maintain suitable conditions.

Temperature Transmitter
Courtesy Smart Sensors

A PLC (programmable logic controller) can be a good candidate for creating your own on/off temperature controller with specialized additional functionality that suits your process. Implementing the temperature control operation is not difficult, and the use of a PLC allows the designer to integrate other useful functions into a single piece of hardware, functions that might not be available in a commercially available process controller.

The primary input device will be a transmitter with analog output compatible with the analog input on the PLC. For this discussion, let's assume this is a temperature control application that requires heating of the process. So, a temperature transmitter will be our primary input device. The primary output device will be a heater contactor or other power control device, the input of which must be compatible with the output of the PLC. Any other switches, pilot lights, alarms, or other devices will need to also be associated with a compatible PLC I/O point. 

The logic portion of the temperature control activity is not complex. The input signal from the temperature transmitter is converted to a working value. Depending upon the numeric muscle of your PLC, this value may be a floating point number, but integer values work suitably. Here are the logic steps needed.

• Read temperature input value
• Is temperature greater than or equal to the setpoint? If yes, turn off output for heater and proceed to the next step. If no, go to next step.
• Is temperature less than or equal to the value of setpoint minus a deadband value (more on deadband below)? If yes, turn on output for heater. If no, continue to other commands that provide your additional desired functions.

Here are some points to consider.

• Use a greater than or equal to, or less than or equal to comparison to assure that all possible numeric scenarios for process temperature are handled.
• Deadband is a value that you employ to keep your control output from chattering rapidly between the on and off state when the process value is very close to the setpoint. It can also be used, in this case, to slow down the on/off switching of the heater and reduce wear on a mechanical contactor. Keep in mind that a 16 or 32 bit number, which is what the PLC will use for internal processing of your temperature reading, may actually pass across the setpoint value rapidly, even though a digital display of temperature will appear to be relatively stable. The constantly changing values would cause rapid changes in the output if the comparison logic did not include a deadband value. The use of a deadband creates a range of process temperature where no change in the output occurs. 
• For this particular application, with its heating action, a separate limit control is advised. The device should derive its input signal from a source other than that of the PLC and the output of the limit control should provide a positive means of de-energizing the heater.
• Other functions easily programmed into the PLC include alarms, pilot lights to reflect heating activity, an on/off switch for the process, and other items limited only by your ingenuity.

Not every process needs PID control. This illustration focused on temperature, but the principles are the same for almost any process. A modestly powerful PLC can provide the processing power, and input devices for temperature, humidity, moisture, pH, liquid level, flow, pressure, and more are available. Share your challenges with a process measurement specialist and develop an effective customized solution for control of your process.

Intelligent Management for Process Sensors

Process analytical sensors can require scrupulous levels of attention and maintenance to continually deliver optimum performance. In some cases, overly frequent or involved maintenance is performed in order to avoid problems. Mettler Toledo, globally recognized leader in the development of process analytical sensors, developed a solution to streamline sensor maintenance and maximize reliability and performance.

The iSense software suite supports Mettler Toledo's line of intelligent sensors, monitoring and documenting sensor performance while maintaining real time indications of time to maintenance and calibration. Essentially, the iSense software provides guided sensor maintenance and continually verifies the operational health of the sensor to assure that delivered data is accurate and reliable.

There is much more to learn about how the iSense software and comprehensive offering of intelligent sensors can enhance process performance, as well as the efficiency of analytical operations. Reach out to a process analytics specialist with your analytical measurement challenges. Combining your process knowledge and experience with their product application expertise will yield an effective solution.

Improve Liquid Processing Performance With Sensor Technology

In the field of industrial processing, there is always a striving for improvement. Increasing output, improving output, and decreasing resource input are the watch phrases for process designers and operators in every industry.

Liquid processing often involves analytical instruments that produce periodic or continuous measurements of process conditions. The accuracy of these instruments will directly impact the quality and efficiency of the process, so great attention is paid to maintaining sensors and related instrumentation in top working order. Mettler Toledo, globally recognized leader in analytical sensor technology, provides a comprehensive solution for liquid analytical operations with its line of smart sensors and companion management software.

The ISM sensor technology couples the sensor with an onboard processor that continuously monitors sensor performance and delivers real time information about accuracy and time before maintenance. This empowers users to efficiently schedule maintenance tasks and operate with assurance that the data delivered by the sensor is reliable.

The video below sums up the ISM sensor benefits in under one minute. Share your process analytical challenges with application specialists and combine your process knowledge with their product application expertise to develop effective solutions.

Digital Sensor Technology For In-line Process Analytics

Digital sensor technology opens new
avenues for accuracy and efficiency
Courtesy Mettler Toledo

In-line process analytics deliver wide ranging data used to control production processes and assure the suitability and performance of end products. Strict adherence to established procedures and standards contribute to the accuracy and value of the measurements derived from instruments and equipment monitoring various process steps from start to completion.

Digital sensor technology, with an onboard microprocessor, provides a wealth of functionality not previously available that enhances accuracy and efficiency. Mettler Toledo is at the forefront of digital sensor technology for inline process analytics with their line of ISM (Intelligent Sensor Management) compatible sensors. The digital sensors interface with companion transmitters and software tools to deliver customers top flight process analytics performance.

• Simplified workflow.
• Increased measurement effectiveness and process confidence.
• Sensors are easily removed from the process for calibration, negating need for personnel to bring calibration gases or buffer solutions to the measurement point.
• Diagnostic functions provide easy to read tools, notifying operators of when and what to do to maintain proper performance.
• Each sensor stores its own set of calibration data, which is automatically uploaded to the companion transmitter.
• Self configuration executed when new sensor connected to transmitter.
• Supporting software facilitates the range of tasks necessary to maintain top flight operational status for every ISM sensor.
• Sensor output is a digital signal, not prone to degradation in the same manner as analog signals.
• Sensor learns from and adapts to process conditions to provide better overall performance.

There is much more to learn regarding how ISM sensors can dovetail into your process operation and deliver substantial increases in efficiency and accuracy. The document below provides the next layer of information. Reach out to an inline process measurement specialist, sharing your process measurement challenges. The combination of your process knowledge and their product application expertise will yield an effective solution.

Intelligent Sensor Management For Inline Process Analytics from Alliance Technical Sales, Inc.

New M300 Series Single and Multi-Variable Transmitters From Mettler Toledo

Mettler Toledo recently introduced a new line of transmitters to deliver maximum effectiveness from their array of water quality and process analytics sensors. The M300 is available in 1/2 DIN and 1/4 DIN sizes, with a single or dual channel configuration. Two versions are tailored for process analytics applications or water quality applications. Analog or digital ISM sensors for pH/ORP, conductivity, dissolved oxygen and ozone can be utilized with the new transmitter, which features intuitive operation and excellent ergonomics.

Learn more about the M300 transmitter and see it in action in the video. Reach out to a product specialist with your water and process analytical challenges, combining your process knowledge with their product application expertise to develop effective solutions.

New Dissolved Ozone Sensor

Mettler Toledo, under the Thornton brand, has released a dissolved ozone sensor employing the company's Intelligent Sensor Management technology that helps to streamline the use of sensors for measuring pH, conductivity, dissolved oxygen or ozone, and a host of other aspects of pure water. The pureO3 sensor technology provides rapid response in a sensor assembly with a built in digital measuring circuit and Intelligent Sensor Management (ISM®). The pureO3 is designed for monitoring low concentrations of dissolved ozone in semiconductor and pharmaceutical pure water samples, bottled water and similar applications. Minimal maintenance requirements and reliable long-term operation are hallmarks of this sensor.

How it works, in the company's own words...

"The pureO3 sensor uses a gas permeable membrane to separate the sample from the electrochemical cell inside. Ozone diffuses through the membrane in direct proportion to the partial pressure of ozone outside the sensor.The cathode and anode inside the sensor are polarized with a voltage to enable the electrochemical reaction of ozone. Ozone is reduced at the cathode while the anode is oxidized, producing a current in direct proportion to the amount of ozone present. The very low current developed by these sensors allows them to have a long life with low maintenance. An embedded temperature sensor enables temperature compensation to adjust for the changing permeability of
the membrane with temperature. In addition, the instrument uses the temperature value to convert the ozone partial pressure signal to a dissolved ozone concentration value by compensating for the changing solubility of ozone with temperature."

Benefits to the user from the ISM® based sensor.

• Full sensor identification by type and serial number.
• Calibration history with actual calibration, factory calibration, and last three calibration.
• Programmable timer to facilitate maintenance planning, reducing downtime.
• Starting calibration interval of 90 days.
• Time to maintenance function integrates ozone concentration over time, indicating replacement time for membrane body and electrolyte.
• Dynamic Lifetime Indicator for inner body used ozone concentration integration to predict life of inner body and membrane. Starting values, membrane body lifetime 180 days, inner body 1080 days.
• Sanitization counter allows the limit of ozone concentration and duration of sanitization cycleto be defined on the transmitter.

The pureO3 sensor with ISM operates with the M800 and M300 transmitters. ISM features enable users to maximize the lifetime of the sensors and minimize downtime by predicting when sensor maintenance is required. Contact a product application specialist for all the details. Share your process measurement challenges with experts, combining your process knowledge with their application expertise to develop the best solutions.

Technical Reference for Thermocouples and Reistance Temperature Detectors (RTD)

One of many industrial
temperature sensor
configurations
Smart Sensors, Inc.

Temperature measurement is probably employed in process control more than any other physical property measurement. Methodology for temperature measurement is well established, as is the industry providing instruments and devices for acquiring temperature data from almost any facet of any process. If you are even peripherally involved in process measurement and control, having a solid understanding of how thermocouples and RTDs work is a requisite to solving problems or servicing customers.

One manufacturer of a comprehensive line of thermocouple and RTD assemblies, Smart Sensors, Inc., produced a technical manual with all you need to know about temperature sensors for process measurement and control. The manual is included below for easy reference. It covers:

• Thermocouple theory
• RTD and thermocouple specification criteria
• Cable specifications for both sensor types
• Comparison of thermocouple and RTD attributes
• Thermowell and protection tube specification and selection
• Specifying temperature sensors for hazardous areas
• Reference data tables for both sensor types
• Practices for improving temperature measurement
• Calibration

The tech manual should be on the shelf or cloud drive of anyone involved in accomplishing, interpreting, or maintaining temperature measurement. The configuration options for temperature sensor assemblies are extensive. Reach out to a product application specialist and combine your process knowledge with their product application expertise to develop effective solutions to temperature measurement challenges.

Technical Reference for Thermocouples and Reistance Temperature Detectors (RTD) from Alliance Technical Sales, Inc.

Alliance Adds Thornton to Process Analytical Instrument Offering

Alliance Technical Sales, experienced provider of process analytical solutions throughout many industries, has added the Thornton brand of instruments to expand its offering of Mettler Toledo analytical products. Thornton specializes in on-line liquid process measurement solutions for pure and ultrapure water applications. The product line includes instrumentation and sensors providing high quality measurement of conductivity/resistivity, TOC, pH, ORP, dissolved oxygen, dissolved ozone, sodium, silica and bioburden. The Thornton line complements and expands the extent of Mettler Toledo products already available from Alliance Technical Sales.

Share your fluid process analytical challenges with product application experts, combining your process knowledge and experience with their product application expertise to develop effective solutions.

Process Analytics Product Catalog from Alliance Technical Sales, Inc.

Combustion Control in Gas Turbines

Proper inlet air control can boost gas turbine efficiency

Gas turbines continue to enjoy an expansion in their use throughout the world. The benefits of using gas as a fuel are well recognized. Achieving high levels of fuel efficiency will be a goal of every operator, so understanding the nature of combustion and fuels can be useful in attaining optimum operating conditions.

Vaisala, a globally recognized leader in the measurement of temperature and humidity, was authored a white paper application note that explains how the temperature and humidity of inlet air can contribute to combustion efficiency, as well as providing recommendations for measuring these parameters in gas turbine applications.

The white paper is included below. Share your process measurement requirements and challenges with application experts. Combine your process knowledge with their product application expertise to deliver effective solutions.

Optimizing gas turbine performance with precise humidity measurements from Alliance Technical Sales, Inc.

Close Temperature Control of a Process Fluid Flow

Temperature sensor is one component
of a successful temperature control
system
Courtesy Smart Sensors, Inc.

Temperature control is a common operation in the industrial arena. Its application can range across solids, liquids, and gases. The dynamics of a particular operation will influence the selection of instruments and equipment to meet the project requirements. In addition to general performance requirements, safety should always be a consideration in the design of a temperature control system involving enough energy to damage the system or create a hazardous condition.

Let's narrow the application range to non-flammable flowing fluids that require elevated temperatures. In the interest of clarity, this illustration is presented without any complicating factors that may be encountered in actual practice. Much of what is presented here, however, will apply universally to other scenarios.

What are the considerations for specifying the right equipment?

KNOW YOUR FLOW

First and foremost, you must have complete understanding of certain characteristics of the fluid.

• Specific Heat - The amount of heat input required to increase the temperature of a mass unit of the media by one degree.
• Minimum Inlet Temperature - The lowest media temperature entering the process and requiring heating to a setpoint. Use the worst (coldest) case anticipated.
• Mass Flow Rate - An element in the calculation for total heat requirement. If the flow rate will vary, use the maximum anticipated flow.
• Maximum Required Outlet Temperature - Used with minimum inlet temperature in the calculation of the maximum heat input required.

SELECT SYSTEM COMPONENTS WITH PERFORMANCE TO MATCH THE PROJECT

• Heat Source - If temperature control with little deviation from a setpoint is your goal, electric heat will likely be your heating source of choice. It responds quickly to changes in a control signal and the output can be adjusted in very small increments to achieve a close balance between process heat requirement and actual heat input. 
• Sensor - Sensor selection is critical to attaining close temperature control. There are many factors to consider, well beyond the scope of this article, but the ability of the sensor to rapidly detect small changes in media temperature is a key element of a successful project. Attention should be given to the sensor containment, or sheath, the mass of the materials surrounding the sensor that are part of the assembly, along with the accuracy of the sensor.
• Sensor Location - The location of the temperature sensor will be a key factor in control system performance. The sensing element should be placed where it will be exposed to the genuine process condition, avoiding effects of recently heated fluid that may have not completely mixed with the balance of the media. Locate too close to the heater and there may be anomalies caused by the heater. A sensor installed too distant from the heater may respond too slowly. Remember that the heating assembly, in whatever form it may take, is a source of disturbance to the process. It is important to detect the impact of the disturbance as early and accurately as possible.
• Controller - The controller should provide an output that is compatible with the heater power controller and have the capability to provide a continuously varying signal or one that can be very rapidly cycled. There are many other features that can be incorporated into the controller for alarms, display, and other useful functions. These have little bearing on the actual control of the process, but can provide useful information to the opeartor. 
• Power Controller - A great advantage of electric heaters is their compatibility with very rapid cycling or other adjustments to their input power. A power controller that varies the total power to the heater in very small increments will allow for fine tuning the heat input to the process.
• Performance Monitoring - Depending upon the critical nature of the heating activity to overall process performance, it may be useful to monitor not only the media temperature, but aspects of heater or controller performance that indicate the devices are working. Knowing something is not working sooner, rather than later, is generally beneficial. Controllers usually have some sort of sensor failure notification built in. Heater operation can be monitored my measurement of the circuit current.
  
  

SAFETY CONSIDERATIONS

Any industrial heater assembly is capable of producing surface temperatures hot enough to cause trouble. Monitoring process and heater performance and operation, providing backup safety controls, is necessary to reduce the probability of damage or catastrophe.

• High Fluid Temperature - An independent sensor can monitor process fluid temperature, with instrumentation providing an alert and limit controllers taking action if unexpected limits are reached.
• Heater Temperature - Monitoring the heater sheath temperature can provide warning of a number of failure conditions, such as low fluid flow, no fluid present, or power controller failure. A proper response activity should be automatically executed when unsafe or unanticipated conditions occur.
• Media Present - There are a number of ways to directly or indirectly determine whether media is present. The media, whether gaseous or liquid, is necessary to maintain an operational connection between the heater assembly and the sensor. 
• Flow Present - Whether gaseous or liquid media, flow is necessary to keep most industrial heaters from burning out. Understand the limitations and operating requirements of the heating assembly employed and make sure those conditions are maintained. 
• Heater Immersion - Heaters intended for immersion in liquid may have watt density ratings that will produce excessive or damaging element temperatures if operated in air. Strategic location of a temperature sensor may be sufficient to detect whether a portion of the heater assembly is operating in air. An automatic protective response should be provided in the control scheme for this condition.

Each of the items mentioned above is due careful consideration for an industrial fluid heating application. Your particular process will present its own set of specific temperature sensing challenges with respect to performance and safety. Share your requirements with temperature sensing experts, combining your process knowledge with their expertise to develop safe and effective solutions.