Showing posts with label New Jersey. Show all posts
Showing posts with label New Jersey. Show all posts

The Yokogawa YS1700 Single Loop Controller Replaces Obsolete Moore/Siemens 353

Yokogawa YS1700

Now that entire Moore/Siemens 350 family is obsolete, are you considering upgrading to a DCS? 


Are you concerned about the cost and time for a new installation, application development and personnel training?

Is it possible that the new equipment vendor may again leave you stranded with their equipment as their core business is not industrial automation and control?

We have a better solution for you: Yokogawa and its YS1700 PID loop controller. Yokogawa has been providing industrial solutions, as their primary business, for over a century and their YS1700 will keep you off of eBay looking for spare 353 parts.

Interface in the Field: Achieving Reliable Interface Measurement to Optimize Process and Increase Uptime

Interface or multiphase level measurements exist throughout the Oil & Gas streams as well as Petrochemical. While level measurement technologies have come a long way in effectively measuring liquids and solids, multiphase level measurement continues to be the biggest challenge and opportunity that exists today to which there is no perfect technology.

However, experience has shown that process optimization and increased uptime can still be achieved in many separator applications through reliable, best-in-class, level technology.

The objective of this paper is to review interface challenges, the current technologies being utilized for interface, field experience in various applications to achieve process optimization and increased uptime, and the future of reliable interface measurement.

DOWNLOAD THE TECHNICAL PAPER HERE

Courtesy of Magnetrol and Miller Energy, Inc.
https://millerenergy.com
800-631-5454

The Magnetrol ECHOTEL 962 Dual Ultrasonic Level Control


The Magnetrol ECHOTEL Model 962 is a dual point switch that can be used as a level controller, or to control pumps in an auto fill or auto empty mode. The tip sensitive lower gap performs well in aerated or foamy liquids, and can measure to within 1.4" of the vessel bottom. The rigidity of the unique flow-through upper gap allows separations of up to 125" (318 cm) between the upper and lower transducer gaps.

The Magnetrol ECHOTEL 962 offers the ultimate solution to reliable dual point liquid level measurement. This advanced switch uses pulsed signal technology for superior performance in difficult process conditions, and to provide excellent immunity from sources of electrical noise interference. Extensive self-testing of the electronics and transducer make this advanced switch suitable for use in Safety Integrity Level (SIL) 2 loops.

The ECHOTEL Model 962 is equipped with advanced diagnostics that continuously check the sensor and electronics. The diagnostics also alarm for electrical noise interference from external sources.

Ultrasonic contact switches use a pair of piezoelectric crystals that are encapsulated in epoxy at the tip of the transducer for level measurement. The crystals are made of a ceramic material that vibrates at a given frequency when subjected to an applied voltage. The transmit crystal converts the applied voltage from the electronics into an ultrasonic signal. When liquid is present in the gap, the receive crystal senses the ultrasonic signal from the transmit crystal and converts it back to an electrical signal.

Miller Energy, Inc.
https://millerenergy.com
800-631-5454

ASCO Express Product Catalog

The ASCO Express program features a range of flow control products and accessories available for shipment the same day you order them. The products listed in this catalog provide the performance required for a variety of system and process applications including boiler, air handling, process control, and water and steam control. The control voltages available for each product are the primary voltages used in industrial and commercial applications today.

908-755-6700

Water and Wastewater Treatment Applications for the Magnetrol R82 Pulse Burst Radar Transmitters


The Magnetrol R82 Pulse Burst Radar transmitter performs across a wide range of applications. The R82 is designed to provide radar reliable process measurement in challenging, vapor saturated environments, at the cost of what you pay for an ultrasonic device. For water treatment, the Magnetrol R82 Pulse Burst Radar transmitter provides continuous level measurement at the lift station and coagulant feed tanks, in settling tanks during clarification, in polymer, filter, and lime slurry tanks during filtration, and for open atmosphere water reservoirs where the control technology must withstand punishing weather conditions.  In wastewater facilities, the R82 radar can control level at the lift station pump, open channel flow and screening system, monitor feed tanks containing chemical coagulants oxidants and phosphorous precipitation, measure splitter box in clarifier levels, control corrosion inhibitors, manage pH adjustment, mixed liquor and secondary clarifier levels, as well as activated sludge and digester level control.

Miller Energy, Inc.
https://millerenergy.com

Brooks Instrument Sponsoring $2000 Engineering Scholarship

CLICK THIS LINK TO LEARN MORE

Brooks Instrument is committed to the next generation of engineers. Accordingly, they have established a $2,000 scholarship for a qualified student enrolled in an engineering program at an accredited college or university. Learn more here (https://www.brooksinstrument.com/en/about-us/scholarship).

Temperature Switches

temperature switch
Temperature switch
(United Electric Controls)
A temperature switch detects the temperature of some substance. Temperature switches often use bimetallic strips as the temperature-sensing element, the motion of which actuates one or more switch contacts. An alternative design uses a metal bulb filled with a fluid that expands with temperature, causing the switch mechanism to actuate based on the pressure this fluid exerts against a diaphragm or bellows. This latter temperature switch design is really a pressure switch, whose pressure is a direct function of process temperature by virtue of the physics of the entrapped fluid inside the sensing bulb.

The “normal” status of a switch is the resting condition of no stimulation. A temperature switch will be in its “normal” status when it senses minimum temperature (i.e. cold, in some cases a condition colder than ambient). For a temperature switch, “normal” status is any sensed temperature below the trip threshold of the switch.

switch contacts

Like all other process switches, temperature switches exhibit a certain amount of deadband in their switching action. A temperature switch that trips at 300 F rising, for example, will not reset at 300 F falling. That switch would more likely reset at some lower temperature such as 295 F. With mechanical switch designs, some amount of deadband is inevitable due to friction inside the mechanism. However, process switch deadband is actually a useful characteristic as it helps avoid repeated “nuisance” alarms from happening.

To understand this concept, it is helpful to imagine a scenario where the process variable is at or very near the trip point. For our hypothetical temperature switch with a trip point of 300 F (rising), imagine a situation where the process temperature is precisely 300.0 F. Any further rise in temperature will of course trip the switch (sounding an alarm). With no deadband, however, the switch will immediately re-set when the temperature falls back down to 300.0 F. This means the switch may possibly “cycle” back and forth between its trip and reset states with just a minute change in process temperature (300.0 F to 300.1 F and back again). If the temperature switch is activating an alarm every time it trips, it will create a series of alarm events prompting operators to repeatedly acknowledge the alarm. This is a nuisance to operations personnel, as it distracts them from addressing what they already realize is a process problem. It is better for the switch to trip at 300.0 F rising and remain in that tripped state until the temperature falls down to some degree substantially below the trip point. This way, the operators only receive one alarm event rather than multiple alarm events for each process temperature excursion.

Some mechanical temperature switches come equipped with a separate adjustment for deadband (also called differential). Setting this deadband adjustment in a mechanical temperature switch requires the technician to repeatedly subject the sensing element to a rising and falling temperature, to check that the switch trips at the proper setting and resets at the proper setting. This is analogous to cycling the process variable back and forth when adjusting the “zero” and “span” settings of an analog transmitter: checking to see that the transmitter repeatedly outputs a 0% signal at the lower range value (LRV) and a 100% signal at the upper range value (URV). 

For discrete temperature-sensing applications demanding high accuracy and repeatability, electronic temperature switch circuits using thermocouples, RTDs, or thermistors may be used instead of a mechanical (bi-metallic or filled bulb) sensing element. The operation and configuration of discrete electronic temperature switches is very similar to that of continuous electronic temperature transmitters.

An example of an electronic temperature switch module is the United Electric One Series shown below:

UE Series One Electronic Temperature Switch
UE Series One Electronic Temperature Switch

With electronic temperature switches, the adjustment of deadband (differential) is both precise and flexible. Unlike mechanical switches where deadband is primarily a function of friction, and therefore liable to change over time as the device wears, electronic switching circuits may be precisely set for any trip and reset points along its measurement range, remaining very stable over time.

For more information about temperature switches, contact Miller Energy by visiting https://millerenergy.com or by calling 908-755-6700.


Text adapted from "Lessons In Industrial Instrumentation" by Tony R. Kuphaldt – under the terms and conditions of the Creative Commons Attribution 4.0 International Public License.

How Do Pilot Operated Tank Relief Valves Work?

Storage tanks become pressurized when liquid is pumped in and compresses the existing tank vapor. Tanks also become pressurized due to increasing ambient temperatures, which cause the tank vapor to expand. To mitigate damage from these expanding tank vapors, pressure relief valves are installed on tanks to prevent structural damage resulting from over-pressure.

Here is an excellent animation, courtesy of Cashco, that shows how a pilot operated relief vent protects a storage tank from over pressurizing during a pump-in situation or during thermal heating conditions.


For more information on tank relief valves, contact Miller Energy at www.millerenergy.com or by calling 908-755-6700.

Common Instrumentation Requirements for Industrial Boilers

Instrumentation Used on Industrial Boilers
Typical boiler instrumentation layout.
(courtesy of Yokogawa)
Boilers are used in a broad range of industries such as electric power, pharmaceuticals, chemicals, ceramics, and paper and pulp. Amid the rising energy costs, tightening environmental regulations, and increasing awareness of safety as of late, the needs for high efficiency operation, low emission operation, and safe and stable operation of boilers are growing.

In order to ensure the air and fuel are combusted at an optimal ratio, the waste of fuel is eliminated, and the exhaust gas is cleaned, real-time monitoring of the oxygen concentration of combustion gases is required. Equipped with an oxygen sensor unit with a longer life span, the Zirconia Oxygen Analyzer ZR series are capable of measuring an oxygen concentration with high reliability. The Stack Gas Analyzer monitors exhaust gas components such as NOX, SO2, and CO2 in order to ensure low emission operation.

A single-loop controller can be used to properly distribute control functionality. Offering the advantages of flexibility of building distributed control systems, simple maintenance, compatibility with conventional systems, and the like, the YS1000 Series of Single-loop Controllers are ideal for safe and stable operation at low costs.

In order to ensure highly efficient and safely operated boilers, it is also indispensable to accurately monitor the drum level and steam flow rate. The EJA and EJX Series of Differential Pressure Transmitters are capable of measuring the drum level with high stability even in actual applications at high temperatures and high pressures. The DY Series MV TYPE of Vortex Flowmeters with a simple construction employ a built-in sensor to measure the steam mass flow with high reliability.

Yokogawa offers a wide variety of sensors and controllers that are used to monitor and operate boilers, and contributes to increasing the efficiency and environmental performance of boilers, as well as ensuring their safe and stable operation.

Recommended Products for Boiler Applications


  • Drum Level Measurement - EJA/EJX transmitters
  • Combustion Control - The YS1000 Dual CPU Loop Controller
  • Steam Flow Measurement - Digital YEWFLO MV Type
  • Combustion Monitoring - Zirconia Oxygen Analyzers and AV550G Multi Oxygen Sensor Converter

For more information in Eastern Pennsylvania, New Jersey, Metro New York or Delaware contact:
Miller Energy by visiting https://millerenergy.com or by calling 908-755-6700 in New Jersey, or 610-363-6200 in Pennsylvania.

Detailed Look at the Yokogawa YS100 Series as a Replacement for the Obsolete Siemens 353

This video is a thorough presentation detailing why and how the Yokogawa YS1000 Series is the best replacement for the obsolete Siemens/Moore 353 controller. It is composed of a series of presentation slides - hit the pause button to focus on any single slide.

New Jersey: 908-755-6700 
Pennsylvania: 610-363-6200

Breakthrough Solenoid Valve Technology for Upstream Oil and Gas Heating Equipment

A white paper courtesy of ASCO Division of Emerson Automation
fuel shutoff valves
Fuel shutoff valves (ASCO)
Low-temperature stainless steel fuel shutoff valves are usually utilized for on/off control of fuel gas within gas fuel trains in process heating system burners. These systems are widely used by oil and gas firms as well by as original equipment manufacturers (OEMs) that produce gas heating equipment or burner management systems (BMSs) and controls in upstream oil and gas pipelines and tanks.

For valve manufacturers, these uses present a relatively specialized, rather challenging application. Environmental conditions at the point of use are often difficult. Ideally, valves should deliver reliable operation despite constraints on factors ranging from power consumption to service availability. Conversely, outdated controls can pose problems — including poor performance, noncompliance with current regulations, and triggering of environmental concerns.

In recent years, a new generation of solenoid valve technology has been changing the shutoff valve game. Their modern designs provide pipeline and tank heating systems with robust, durable performance; safety; and regulatory compliance — all while increasing efficiency and productivity.

Download the PDF version of "Breakthrough Solenoid Valve Technology for Upstream Oil and Gas Heating Equipment" here, or review it in the embedded document below.

Miller Energy, Inc.
https://millerenergy.com
New Jersey: 908-755-6700
Pennsylvania: 610-363-6200

An Excellent Replacement for the Discontinued Siemens 353 SLC

Siemens 353 replacement
The Yokogawa YS1700 is a great replacement to the
discontinued Siemens 353 SLC controller.

The discontinuation of the Siemens 353 SLC controller is a concern to many users of this popular controller. With few alternatives, customers are joking that they'll have to turn to eBay for spare parts. There's a much better solution though. The Yokogawa YS1700 PID loop controller, a drop-in replacement for the Siemens 353 SLC.

The Yokogawa YS1000 Series is the ideal choice for many control applications offering extreme reliability and sophisticated control. This product family has bright, easy-to-read displays, multiple I/O points, and powerful loop tuning. For critical applications, the YS1700 employs dual CPUs for maximum reliability and hard-manual control for added protection. The YS1700’s powerful function block programming allows for custom strategies to control many demanding processes such as boilers and steam generators, PH control, dosing control, and many other demanding plant processes.

To learn more about replacing the Siemens 353 with a Yokogawa YS1700, visit this page or go directly to this link https://millerenergy.com/Siemens-353-Replacement.

How to Select a Pressure Switch

UEC One Series Switch Transmitter Hybrid
UEC One Series Switch Transmitter Hybrid
Reprinted with permission from United Electric Controls

Pressure switches are widely used by many industries and within many applications. The basic function of a pressure switch is to detect a pressure change and convert it into an electrical signal function – typically on/off or off/on. Pressure switches may be of electro-mechanical or electronic/solid-state design (see our ONE Series); and while each may have its advantages, arriving at the correct pressure switch for your application is the same.

Set Point & Deadband


Application set point (sp) is the desired value reached at rising or falling pressure at which the micro-switch changes electrical states. Depending upon the pressure switch function, the micro-switch could be wired to open (turn something OFF)  or close (turn something ON) when set point is achieved, thereby triggering an event such as an alarm, equipment shutdown, or powering up secondary equipment. Ideally, the set point should fall into the mid 50% of the pressure switch range for best performance including repeatability and long life. On an electro-mechanical pressure switch, set point may be adjusted internally or externally either through blind adjustment or reference dial. An electronic pressure switch would have internal or external adjustment via a key pad and digital display or a handheld programmer.
Deadband graph

Deadband (DB) is the on-off differential required to reset the micro-switch. This value may be fixed or adjustable with an electro-mechanical switch and may be up to 100% adjustable on an electronic switch.

Deadband may be an important factor to consider depending upon the application requirements.

System Pressure


Knowing your normal and maximum system pressures will help in selecting a pressure switch with appropriate minimum and maximum operating parameters. Once your set point is established, other factors to consider are vacuum and/or surge pressure that could affect switch operation. This would involve maximum working pressure, over range pressure, and proof pressure specifications of a pressure switch. The relationship between set point and system pressure has a direct effect on switch performance and life.

Electrical Considerations


UEC 100 Series Pressure Switch
UEC 100 Series Pressure Switch
Micro-switches are available in a variety of configurations. The most common for electro-mechanical pressure switches is 15A, 480VAC SPDT (single pole, double throw). The advantage of a SPDT micro-switch is that it offers wiring flexibility to either open or close on pressure change. Other micro-switches available include 1A with gold contacts, useful when working with a PLC, or at the upper end, 30A when switching certain high voltage heaters or motors. Adjustable micro-switches help with deadband adjustment. A DPDT (double pole, double throw) micro-switch would provide two simultaneous functions off of one micro-switch. If a low-high limit alarm and shutdown were required, there are pressure switches that include two SPDT micro-switches that are independently settable.

An electronic pressure switch would use solid-state relays to change states. Like an electro-mechanical switch, the electronic switch can be programmed to open or close on rising or falling pressure. There are different capacities for switching voltage and current depending upon the application requirements.

Process Media and Wetted Parts


The pressure connection and sensor are known as wetted parts since they come into direct contact with the process media. Sensor material is either elastomer (i.e. Buna-N, Teflon®) or metallic (i.e. Brass, Stainless Steel) with metallic or composite pressure connections. The process media must be compatible with the wetted parts material. Process media temperature should also be considered as each of the different wetted materials would have differing operating properties.

Pressure Switch Mounting


If the unit is to be installed directly onto the process, there are many methods of installation.
Typically a 1/8”, 1/4”, or 1/2” NPT (national pipe thread taper) connection is used with a mating
fitting to secure the pressure switch to the process. There are also straight threaded (SAE, BSPT)
connections, flush mount connections, and sanitary connections. The pressure switch may be
mounted directly in the process line using the threaded connection, a manifold, or flange; or the
enclosure could be bolted to a mounting plate or other plane to secure it. If heavy vibration is
present, you may choose to use a remote diaphragm seal with the pressure switch. The diaphragm
seal mates with the process connection while the pressure switch enclosure is mounted securely
away from the vibration. 

Process Environment


It is important to know what type of environment the pressure switch would be installed in – hazardous or ordinary location; indoors or outdoors; exposed to salt air; inside a control panel; in high ambient temperature. These are just some of the factors to consider so the right enclosure type is chosen. Enclosure types come in many shapes, sizes, and materials. They also conform to various industry and third-party approval standards. Electronic switches can be used to replace electro-mechanical switches when SIL is needed for safety applications.  There are also electro-mechanical pressure switches without enclosures; typically used in OEM, non-hazardous locations where the environment is benign.

With careful consideration of all the factors listed above, choosing a pressure switch is a snap. If you are at all unsure, please contact your local United Electric Distributor or visit the UE Product Selector to find your pressure switch.

Miller Energy, Inc. - Expertly Serving These Industries in the Mid-Atlantic Region

Miller Energy is a Manufacturer's Representative and Distributor of Industrial Instrumentation and Process Control Equipment with offices in South Plainfield, NJ and Exton, PA. In business since Since 1958, Miller's success is attributable to their commitment to exceeding their customers expectations and a comprehensive line of "best-of-breed" measurement, control, and communication products. With a strong reputation for unparalleled customer service and expert local technical support,  Miller Energy continues to demonstrate strong growth in the Mid-Atlantic region.


https://millerenergy.com
908-755-6700 NJ
610-363-6200 PA

Radiometric, Non-contact Level Measurement for Liquids or Solids

Radiometric level detection
Radiometric level detection
(RONAN)
Radiometric level measurement, using a very low gamma level source, is designed to deliver outstanding performance in a wide range of difficult applications and process conditions for both liquids and bulk solids which include the most dangerous materials such as caustic, toxic, corrosive, explosive, and carcinogenic irrespective of their viscosity and temperature.

These level gauges meet “As-Low-As-Reasonably-Achievable” (ALARA) guidelines. Source activity is customized depending on vessel and process parameters such as diameter, wall thickness, material, and measurement span to ensure optimum sensitivity, economy and safety while keeping the source activity to a minimum.

Non-contact level
Sources and Detector Mounted
External to Vessel
An exclusive “Radiation Low Level” (RLL) source holder uses up to 100 times less gamma energy than comparable gauges, and is the only source holder recognized by the NRC to be so safe that it does not require the stringent documentation, training or handling procedures of other systems.

Operation

Radiometric level measurement provides a safe and efficient, non-contact method to measure liquids or solids in harsh process environments. Each system consists of a gamma source, detector and microprocessor.

  • The gamma source, typically mounted external to the vessel emits energy through the vessel walls collimated in a direction towards the detector mounted on the opposite side of the vessel. The gamma energy reaches the detector when the vessel is empty. As the process level rises in the vessel, the gamma energy reaching the detector will decrease in an inversely proportional relationship to the level. 
  • The detector measures the level of energy and sends a proportional signal to the microprocessor. 
  • The microprocessor linearizes, filters, and correlates this signal to a level measurement. 

The entire system is mounted external to the vessel and can be easily installed and maintained while the process is running ... without expensive down time, vessel modifications or chance of accidental release.

Applications
Low Level Source and Detector
Low Level Source and Detector
Mounted External to Vessel
  • Radiometric level detection
  • Low Level Source and Detector
  • Mounted External to Vessel
  • Solids or Liquid Measurement 
  • Measurement Not Affected by: 
  • Internal Obstructions. i.e. Agitators Extreme Process Temperatures 
  • Caustic Processes 
  • Violent Product Flow 
  • Sterile Process 
  • Changing Process 
  • Variable Product Flow 
  • Automatic Compensation for Vapor Density Changes 
  • Automatic Compensation for Foam or Gasses 
  • Automatic Compensation for Process Build-Up 
  • Detectors Contoured to the Shape of Vessels 
  • Upgrade Utilizing Existing Sources
Features and Benefits 
  • Accurately Measures the Most Complex Processes 
  • Solid Crystal or Flexible Scintillating Fill- Fluid 
  • Excellent Measurement Reliability due to Proprietary Filtering Technology 
  • Level Detection of Multiple Interfaces 
  • Low Maintenance / No Component Wear 
  • Auto-Calibration

For more information in Eastern Pennsylvania, New Jersey, Metro New York or Delaware contact:
Miller Energy by visiting https://millerenergy.com or by calling 908-755-6700 in New Jersey, or 610-363-6200 in Pennsylvania.

Industrial Refractometers Used in Process Control

Refractometer Pharmaceutical Use
Refractometer for pharmaceutical use (K-Patents).
Part physics, part material science and part chemistry, refractometry is the process which measures the composition of known substances by means of calculating their respective refractive indexes (RI). RIs are evaluated via a refractometer, a device which measures the curve, or refraction, resulting when the wavelength of light moves from the air into and through a tested substance. The unitless number given by the refractometer, usually between 1.3000 and 1.7000, is the RI. The composition of substances is then determined when the RI is compared to a standard curve specific to the material of the substance.

Process refractometers provide the analysis to quickly, reliably, and very accurately identify a sample and determine it's concentration and purity levels. They measure the refractive index and temperature of flowing liquids, and apply mathematical functions to determine the concentration of dissolved solids.

Common industrial refractometer applications are:
  • Calculating beverages’ amount of sugar dissolved is water.
  • In commercial food applications such as juice production or tomato processing, refractometers are used to measure degrees Brix (Tthe Brix scale relates refractive index to sugar concentration, and is a key way to maintain consistency).
  • In the pharmaceutical industry, process refractometers are used to monitor and control concentration levels during supersaturation, a critical process in crystallization.
  • In pulp and paper production, process refractometers for measuring dissolved solids in black and green liquor during the chemical recovery process.
Equipment manufacturers have developed numerous refractometer configurations tailored to specific each use and application. Each has a set of features making it the advantageous choice for its intended application. Product specialists can be invaluable sources of information and assistance to potential refractometer users seeking to match the best equipment to their application or process.

For more information on industrial refractometers, contact Miller Energy by visiting https://millerenergy.com or by calling 908-755-6700 in New Jersey or 610-363-6200 in Pennsylvania.

Laboratory Flame Testing of Industrial Pressure Gauges: Wika vs. Competitor

Laboratory flame testing of industrial pressure gauges. Manufacturer Wika versus a competitor. The test is structured in (3) stages: a 10 second burn, a 30 second burn, and then a one minute burn. The Wika gauge maintains its reading, does not melt, and does not continue to burn.

https://millerenergy.com
New Jersey 908-755-6700
Pennsylvania 610-363-6200

Flow & Pressure Instrumentation for Biopharmaceuticals & Life Sciences

Flow & Pressure Instrumentation for Biopharmaceuticals & Life SciencesProducing biopharmaceuticals is one of the world’s most demanding manufacturing processes.

Brooks Instrument’s mass flow and pressure control technology helps maximize cell culture yields and control bioprocess costs. Their flow
and pressure controllers set global standards for reliability, repeatability and long-term stability.

Brooks Instrument mass flow controllers (MFCs) satisfy key biotechnology research and production requirements:
  • Tight control of DO and pH during experiments and production
  • NO unplanned downtime due to high cost of losing a batch or experiment
  • Ability to rapidly diagnose and resolve issues with bioreactors or fermentation equipment
  • Cost-effective method for adhering to regulatory requirements
  • Excellent technical support and rapid response for equipment service


What Advantages Do Displacer Transmitters Have Over Differential Pressure Level Transmitters?

Displacer Transmitters
Displacer
Transmitter
(Magnetrol)
Many technologies have been available over the years have helped the process control industry with level measurement. From basic mechanical float-operated level switches, the process automation industry has been developing new technologies to make industry safer and more efficient.

An example of a "tried and true" technology that was commonly used in the process automation industry is the DP (differential pressure) level transmitter. First introduced in the 1950s, DP transmitters measures the hydrostatic (head) pressure of a liquid in a tank or vessel and interprets this as level, based on the density/specific gravity of the liquid and programmed in by the user. A newer, alternative technology to DP transmitters is the displacer level transmitter, a device also based on specific gravity. While they both are dependent on specific gravity, they are significantly different in areas of installation, accuracy, and maintenance requirement.

Application/Calibration

Applying a DP transmitter or displacer level transmitter requires experience and there are many factors to be considered. Here are a few:

DP transmitters use inferential measurement to determine level measurement from the hydrostatic pressure.  Despite requiring the specific gravity variable having to be programmed into the transmitter electronics, the level displacer transmitter is in contact with the process media and the level measurement is direct.

DP transmitters requires time consuming and expensive calibration/re-calibration if any of the set-up parameters change or if the same DP transmitter is used on different materials in the same tank.
Displacer transmitters only require two variables to be programmed (temperature and specific gravity), making it easier when running multiple products in the same tank.

Many displacer transmitters do not require liquid to be present for calibration. They are programmed (wet or dry) using software. A huge time and money saving over DP transmitters.

Mounting

The physical mounting of DP transmitters is limited, which can in some situations can become downright problematic. DP transmitters require (2) side-mounted entry locations on the vessel or tank, with one having to be near the bottom. As a general rule, the fewer the entry points of a tank or vessel, the better, because of leakage. Tank bottom entries all the more so.

Displacer transmitters are mounted to meet the requirements of the application and do not require a connection at the bottom of the tank.

Installation Cost

While DP transmitters have a lower unit cost, adding ancillary components such as tubing and heat tracing can quickly "level" the installation cost playing field. Furthermore, don't discount the time cost savings when setting up, calibrating and re-calibrating displacer transmitters.

Temperature Range

DP transmitters have a normal operating temperature of up to 250°F, with an upper limit of 650°F when special options are specified.

Displacer transmitter can be used up to 850°F, very helpful particularly with level measurement in a hot oil separator application.

There are many options and variants to accommodate industrial level applications. Share your level application challenges with instrumentation specialists, leveraging your own knowledge and experience with their product application expertise to develop the most effective solution.

Cashco / Valve Concepts Model 3100 Packing Material Removal and Weight Installation Instructions

Valve Concepts Model 3100
Valve Concepts Model 3100
The Model 3100 end-of-line conservation breather vent is part of the Valve Concepts, Inc. modular vent product line. The Model 3100 can easily be field converted to a vacuum only vent, a pressure/vacuum vent with pipe away and can either be direct acting or pilot operated.

The Model 3100 end-of-line conservation breather vent is designed for use on atmospheric and low-pressure storage tanks where pressure and vacuum relief is required.

How it Works

Weight loaded pallets in the vent housing allow the intake of air and the escape of vapors as the tank breathes due to thermal changes and product movement in and out of the tank. The pallets open and close to permit in breathing and out breathing necessary to maintain the tank pressure within permissible limits to avoid damage to the tank.