Advanced Water Level Monitoring in Sewage Pools

The complex sewage system of a power plant necessitates immediate maintenance and management. The water utilized for operating turbines and other waste materials runs through the sewage system, and ultimately to the municipal wastewater treatment facility.

Some treatment pools are located in isolated areas around the plant, making it challenging for maintenance staff to access and repair damage promptly. Plant maintenance personnel continually look for ways to more effectively manage the pools and avoid situations where wastewater could overflow.

With the sewage system linked to a central control room, data from each sewage pool has to be transmitted to the primary Distributed Control System (DCS). To achieve optimal management of the sewers, continuous monitoring and attendants are usually necessary.

Technicians understand that sewer blockages inevitably lead to wastewater flooding due to the time required for the equipment to address the backup. This flooding results in significant damage to the surrounding area. Hence, it is crucial to regulate the wastewater level in the pools to prevent such incidents from occurring.

An outstanding solution for this problem is to install two Drexelbrook USonic continuous level transmitters to monitor level in the sewage pools. The USonic's capability to deliver contactless, continuous, and precise water level readings in the pools provide engineers with a comprehensive understanding of the pools' condition. The device's compact size and integral design facilitate easy installation, enabling a quick and efficient solution. With a measuring range of up to 30 feet, the USonic effortlessly provides water level readings of the 12-foot-high sewage pools. Its scan distance function can identify obstacles in the pool and record interfering signals. The USonic connects to the central control system via a 4-20mA interface, granting the engineers constant oversight of the water levels in the sewers, ensuring that the sewers would maintain the appropriate water level and the system would receive a notification in the event of an emergency.

For more information about the use of Drexelbrook USonic level transmitters in New England, contact:

Piping Specialties / PSI Controls

https://psi-team.com

800-223-1468

Plugged Chute Detection Technology: The Superiority of RF Admittance

The operation of industrial processes is a delicate balance of efficiency, safety, and maintenance. A crucial part of maintaining this balance is ensuring the smooth operation of material handling systems, which often employ chutes to transport bulk materials. One common complication these systems face is the problem of chute blockages or plugging, a critical issue that can lead to costly downtime, equipment damage, and potential safety hazards.

Plugged chute detection technologies mitigate these challenges, offering early detection and warning of chute blockages. However, the effectiveness of these technologies varies, and understanding their characteristics is essential for making an informed decision.

Overview of Plugged Chute Detection Technologies

Plugged chute detection technologies fall into three broadly classified groups, mechanical, acoustic, and electromagnetic methods.

Mechanical systems, such as tilt switches and paddle wheel indicators, are simple and inexpensive but prone to mechanical failure and false alarms due to vibration or material buildup. They also require regular maintenance to function effectively.

Acoustic detectors, on the other hand, utilize microphones to listen for changes in the acoustic signature of material flow. While this can be an effective method, it is sensitive to environmental noise and requires sophisticated signal processing to distinguish between normal and blocked flow.

Electromagnetic methods include capacitive probes, microwave radar, and RF Admittance. These offer non-contact detection and are less prone to false alarms and mechanical failures—however, the material's properties, environmental conditions, and installation setup affect their performance and application.

RF Admittance: The Optimal Choice

After an extensive review of these technologies, RF Admittance emerges as the overall best selection for plugged chute detection for several reasons:

Reliability

RF Admittance technology uses a probe to measure changes in the dielectric constant (a property of materials that affects their response to an electric field) between the sensor and the chute wall. When the chute is clear, the admittance (the measure of how easily a circuit or device allows an electric current to pass) between the probe and chute wall will be at one level, and when the chute is blocked, the admittance will change significantly. This reliable detection method leads to fewer false alarms than mechanical and acoustic systems.

Resistance to Material Buildup

One of the significant advantages of RF Admittance technology is its resistance to material buildup on the probe. The technology uses a driven shield construction that ensures only the material near the active sensor affects the reading. This feature helps to eliminate the risk of false alarms due to material buildup, a common issue in other technologies.

Versatility

RF Admittance technology works with various materials, regardless of their conductive or non-conductive properties, making it a versatile solution in different industries handling multiple types of bulk materials.

The Drexelbrook Solution

The Drexelbrook Plugged Chute Detector consistently identifies whether material is flowing through chutes. If the material ceases to flow due to a blockage, an alarm from the flush-mounted capacitance sensing element will be triggered, prompting further necessary actions such as notifying an operator or shutting down a conveyor belt.

The Drexelbrook detector, also known as a blocked chute switch, reliably tracks the presence or absence of bulk solids material in chutes without compromising flow speed. This cost-effective device ensures the continuous flow of materials.

Its robust sensor design makes this point-level switch optimal for handling materials such as coal, wood chips, ores, and powders. Since it is flush mounted through a chute wall, there is no protrusion into the chute to hinder or obstruct material flow.

The point-level switch can automatically identify and disregard coatings, thus preventing false alarms. It features a universal power supply that auto-detects and adjusts to the input power source.

Unlike similar technologies, the point-level switch for detecting plugged chutes permits remote electronics installation at a convenient or safer location.

The dependable detection of plugged chutes ensures smooth plant operations and significantly reduces the chance of spills due to blockages.

Key Features:

• Availability of both curved and flat sensors
• DPDT relay dry contacts rated at 5A, 120VAC
• Requires less maintenance compared to other technologies; devoid of any moving parts that could potentially hang up or wear out
• Utilizes Drexelbrook PML series electronics
• Auto-detecting supply voltage range: 19-250 VAC, 18-200 VDC, without the need for jumpers

For more information, contact:
Piping Specialties, Inc.
https://psi-team.com
800-223-1468

Level Measurement in the Food Processing Industry

Level sensors and controls are crucial in industrial food processing and production facilities to ensure quality and consistency. These devices monitor and regulate the level of liquids, solids, or granular materials in containers, vessels, or silos. Here are some of the most common types of level sensors and controls used in the industry:

1. Capacitive level sensors: These sensors detect changes in capacitance caused by the presence or absence of material (liquid or solid) in a container. They measure liquids, powders, or granular materials levels in various applications, including food and beverages.
2. Ultrasonic level sensors: Ultrasonic sensors use sound waves to measure the distance between the sensor and the material's surface. These sensors are non-contact and used for measuring levels of liquids or solids in tanks or silos and provide the food industry with accuracy and reliability.
3. Radar level sensors: Similar to ultrasonic sensors, radar level sensors use radio waves to measure the distance between the sensor and the material's surface. They are also non-contact and suitable for liquid and solid materials. Radar sensors are particularly useful in challenging environments with dust, vapor, or foam, making them ideal for food processing applications.
4. Hydrostatic pressure level sensors: These sensors measure the pressure exerted by the liquid column on the sensor at a specific depth. The pressure re-calibrates to a level measurement. They are primarily used for measuring liquid levels in tanks and have broad use in the food and beverage industry.
5. Float level sensors: Float sensors use a floating device to detect the liquid level in a container. The float's vertical or tilting movement triggers a mechanical or electrical signal indicating the liquid level. Food processing plants often use them for simple and cost-effective level measurements.
6. Vibrating or tuning fork level sensors: These sensors use a vibrating probe or tuning fork that changes its vibration frequency when it comes into contact with a material. They can detect the presence or absence of material and provide point-level detection of liquids, powders, or granular materials.
7. Optical level sensors: Optical sensors use infrared or visible light to detect the presence or absence of a material at a specific level. They are suitable for various materials, including liquids, powders, and solids, in food processing applications where minimum contact with the material is essential.

The choice of level sensor and control system depends on factors like the process material, the required accuracy, the process conditions, and the specific application within the food processing facility. Each technology has advantages and limitations, so careful consideration is needed to select the most suitable option for each application.

For more information, contact:

Piping Specialties, Inc.

https://psi-team.com

800-223-1468

SIL Level Switch Is Specifically Designed for Floating Roof Tanks

One of the most difficult and critical applications is measuring the high alarm or potential overfill condition on a floating roof tank containing liquid petroleum products such as crude oil or refined products such as fuel. It normally is comprised of a cylindrical steel tank equipped with an internal or external floating roof, that floats on the surface of the stored liquid. Floating roof tank systems are especially beneficial in eliminating the evaporative losses of the liquids. As opposed to a fixed roof tank there is no vapor space in the tank. This helps to reduce risk in highly explosive vapor environments. This is an extremely high cost of failure application, and one in which only the safest and most trusted products are accepted.

Safe operation of the tank farm relies on critical real time continuous level measurements of the liquids in the tank, as well as detecting when a high level condition exists. Products used in this application are typically required to meet the API 2350 Overfill Protection Standards, as well as SIL Safety Integrity Level performance standards to IEC 61508.

The challenges to reliably detect a high level condition on a floating roof tank are long sensor length requirements, and the variability of what is being measured. The floating roof may be dry in which case you need to detect the position of the physical metal roof. Or there may be a few inches of rain water or petroleum liquids on the roof. Measuring instruments need to determine very accurately, usually within a few millimeters, when the position of the floating roof has reached

The Drexelbrook SIL IntelliPoint capacitance probe level switch is specifically designed for Floating Roof Tanks (internal and external roofs) with a flexible brass level sensing probe. The level probe sensing element is field adjustable for lengths up to 15' (4.6 m). Electronics are designed to meet API 2350 Overfill Protection.

This level measurement system is specifically designed for spill prevention in floating roof tanks (internal and external roofs) using the IntelliPoint level switch with a flexible level sensing element for ease of installation (model 700-0005-595).

This level measurement system meets API 2350 regulations. It is ideal for use in safety related systems with requirements for functional safety for SIL2 in accordance to IEC61508-2, ed2, 2010 (Exida).

To prevent false alarms this level measurement system automatically recognizes and ignores coatings and is supplied with continuous self-test monitors circuits and sensing elements to detect faults.

A dual compartment housing separates the customer wiring from the sensing element and operating circuits. The encapsulated power supply/terminal block design eliminates the possibility of damage caused by moisture in the conduit.

The Floating Roof Tanks system comes with field adjustable lengths from 1' to 15' (0.3 to 4.6 m).

The system is based on our Manual Certify principle which allows the entire system to be manually tested without removing the sensor from the tank. The Manual Certify test checks that the Auto Verify circuits are operating and confirms the probe and cables are properly connected. Furthermore, the Manual Certify feature allows the electronics to sense changes in the probe that simulate contact with the media or floating roof. This provides the user with a method to ensure working performance without having to climb the tank.

No calibration or setpoint adjustments are required.

Key Features

• Loop or Line Powered
• Wetted Parts: 316SS 3/4" NPT Mounting, 3/16" FEP insulated flexible and adjustable cable, non-sparking brass sensor.
• Automatic and local or remote manual test functions ensure proper system operation.
• One system fits most floating roof tank applications, reducing field spans
• Adjustable insertion lengths up to 15' (4,6m)
• Excellent trip point accuracy over a wide range of medias and tank roof

Piping Specialties / PSI Controls

https://psi-team.com

800-223-1468

Industrial Thermowell Process Connection Types

This video covers the common types of thermowell process connections. The styles are referred to by what their process connection is.

The types are threaded thermowell, a flanged thermowell, a welded or weld-in thermowell, and a sanitary thermowell.

Threaded thermowells are commonly used when thermowell removal occurs infrequently. These wells are typically threaded into a welded fitting widely referred to as a weldolet on the pipe or vessel. Typical installations include smaller pipes or vessels where corrosion is not an issue.

Flanged thermowells are the preferred well for applications that require frequent removal or replacement due to corrosion or other hazards. Flanged wells will bolt to a mating flange installed on the process piping. Typical installations include large pipes with high pressure and high corrosion.

Weld-in thermowells are welded directly to the pipe or tank and provide a high-quality connection. Because being welded in, their removal is not easy, and they should only be installed when quick access is not required, and corrosion is not an issue. Typical installations include very high temperature and high-pressure applications, for example, a steam line or other non-corrosive applications.

Sanitary thermowells are generally fitted with a Tri-clamp or other clean-in-place connection. These thermowells also have a smooth surface which allows for easy cleaning and prevents contamination of the process: typical installations include dairy, food processing, and pharmaceutical industries.

Piping Specialties / PSI Controls

https://psi-team.com

800-223-1468

Water Cut Meters from Drexelbrook

The water cut is the proportion of water collected in a well to the total liquids produced. As crude oil and hydrocarbons travel through a pipeline, a water cut meter monitors the amount of water (cut). BS&W is the amount of non-hydrocarbon contaminants, dirt (sediment), and water included in a crude oil shipment. The lower the BS&W, the better.  Water content determination and BSW have been a persistent and long-standing issue for the oil and gas industry.

Water cut meters measure the water cut (or BS&W) of oil flowing from a well,  a separator, crude oil transfer in pipelines, and tanker loading. 

Drexelbrook has been the global leader in capacitive-based water cut measuring. Drexelbrook has the industry's highest pressure and temperature ratings, and their capacitive probes can withstand pressures of up to 1500 psi and temperatures of up to 450°F. 

The Universal IV CM Series from Drexelbrook is a high-quality water cut meter with a range of 0-50 percent in light oil and 0-80 percent in heavy oil. 

The Universal IV CM Series builds upon Drexelbrook's expertise in RF Admittance, which enables the electronics to disregard paraffin and other coatings that accumulate on the probe. 

The Universal IV CM has a one-of-a-kind Cote Shield built into the Universal IV CM series and allows the instrument to disregard a pre-determined length of the sensing element. It contains a Perm-A-Seal sensing device that eliminates the need for epoxy coatings, which wear out and need costly maintenance. 

Field setup is available anywhere along the two-wire loop when using this water cut meter with Drexelbrook's HRTWin or the STExplorer PC program. 

Choose the Universal IV CM sensing element depending on pipe size, wetted portions, NACE requirements, and pressure/temperature requirements. Drexelbrook has a broad assortment of probes to suit almost any purpose. 

All water cut meters have a built-in LCD and keypad, are pre-calibrated at the manufacturer, and need just one point confirmation. 

The Universal IV CM water cut meter is intrinsically safe and approved for Class I, Division 1, and Zone 0 hazardous areas.

For more infomration in New England, contact Piping Specialties / PSI Controls. Call 800-223-1468 or visit https://psi-team.com.

Food Industry Batch Level Control

Many food processing facilities employ batch processes in their production facilities where the operator starts with an empty vessel and create the final product by adding multiple ingredients.

The batch process requires the operator to know the amount of each ingredient added to the blending vessel. Point-level controls speed the process by establishing setpoints at each ingredient fill point,  often accomplished with several level sensors, each detecting one ingredient.

Batch food processing applications are challenging. The sensor must include sanitary fittings and CIP (Cleaned In Place) design. In many cases, the ingredients and final products are dense and sticky, wreaking havoc on some technologies such as mechanical switches and tuning forks. Products in the blending vessel may be thick and could cause damage to fragile sensors. Finally, many batch processes are agitated, causing false tripping due to splashing material. 

As you can tell, proper level sensing technology is critical. Choosing the wrong technology will cause ruined batches, costly downtime, and the possibility of overfilling.

The Drexelbrook Multipoint II offers the best solution for batch process control applications in the food industry.

Drexelbrook, a leading manufacturer of level controls, recommends its RF Admittance Multipoint II. It provides a total solution for the batch processing of food. The RF Admittance Multipoint II is a single sensing element and a single mounting point from the top of the vessel using a sanitary Tri-Clamp fitting and has no moving parts to wear out or get hung up. The Multipoint II sensor is a 3A sanitary designed steel rod with Kynar or TFE insulation developed for CIP procedures. RF Admittance Cote-Shield driven shield circuitry ignores heavy coatings on the sensing element, preventing false alarms. The Multipoint II consists of three independent DPDT relays, and control points are set anywhere along the vertical sensing element.

Drexelbrook Multipoint II Advantages:

• 3A designed sanitary sensing elements
• No moving parts
• 3 control points on one vertical sensing element
• Cote-Shield circuitry eliminates false alarms due to coatings
• Designed to endure Clean In Place (CIP) demands

For more infomration in New England, contact Piping Specialties / PSI Controls. Call 800-223-1468 or visit https://psi-team.com.

The REOTEMP Model W Explosion Proof, Field Mounted, HART Temperature Transmitter

Process control instrumentation monitors and controls a process to maintain proper functioning standards and keep it within a proper functioning and safe operating range. Process variables are the parameters or quantities maintained to keep the process within desired and acceptable limits. Instrumentation systems compare process variables to a desired setpoint and then produce offsetting and corrective control outputs. 

Typical process variables are level, flow, temperature, density, pH (acidity or alkalinity), mass, and conductivity. 

Temperature is a measurement of how hot or cold something is, whether it's an object or a process medium. The temperature setpoint is the process variable's target value for optimum control, quality, and safety. In a process where the temperature stays within plus or minus 1 degree Celsius of 100℃, the setpoint is 100. 

Temperature transmitters are instruments that convert a weak thermocouple or RTD signal to a robust analog (4-20mA or HART) or digital (Profibus or Fieldbus) signal. The temperature sensor and the final control device communicate through the transmitter. Since transmitters provide more robust analog or digital outputs, external signal conditioning and amplification devices are eliminated, thus lowering costs.

The REOTEMP Model W Explosion Proof Field Mounted HART Temperature Transmitter includes a local display, HART compatibility, and a 4-20mA output. The field-mounted transmitter is available as a complete RTD or thermocouple assembly customized to your process. 

The REOTEMP Model W includes linearized temperature measurement with TC and RTD sensors (Pt100 and Ni100) inputs, local display, HART communication, and 4-20 mA analog PV output for individual, difference, or average temperature measurement. It can handle two RTD or TC input sensors, and up to 63 transmitters (HART 7) can connect in a multidrop communication setup.

For more infomration about REOTEMP products in New England, contact PSI Controls / Piping Specialties, Inc. Call 800-223-1468 or visit https://psi-team.com.

Submersible Level Transmitters

AMETEK’s Submersible Level Transmitters are one of the most complete lines in the industry for measuring industrial and water/wastewater plant level. From the low cost Model SDT with a light weight 316 Stainless Steel body that can measures levels up to 345 feet, to the Model 575 and 675 with a 316 Stainless Steel body and Hastelloy diaphragm that can measure up to 690 feet with CSA intrinsically safe approval for hazardous locations, such as lift stations, process sludge tanks, AMETEK offers a series of different products to meet your level needs.

For more information in New England, contact PSI Controls or Piping Specialties. Call 800-223-1468 or visit https://psi-team.com.

The Drexelbrook DR3500 80 GHz FMCW Radar for Liquids With Hygienic Requirements

The Drexelbrook DR3500 is a two-wire open-air radar level transmitter ideal for measuring liquids in hygienic and sanitary applications. 

The DR3500, FMCW 80 GHz radar level transmitter provides cutting-edge performance for liquids in sanitary applications. The DR3500 offers a wide range of hygienic process connections, including flush-mounted PEEK Lens antennas. These are CIP/SIP compatible, and this model has a small dead zone and beam angles, making them ideal for small and narrow tanks. 

PEEK Lens antennas can measure levels up to 50m / 164 feet. This continuous, non-contact level measurement transmitter is ideal for high and narrow tanks and small and agitated tanks. 

The DR3500 is a two-wire radar level measurement instrument with an easy-to-use touch screen user interface and a clear navigation display. This level transmitter can determine the actual level in the tank even with agitated surfaces due to its robust signal processing and large bandwidth.

Key DR3500 Features

• Process conditions up to +300⁰F (150⁰C) and 362 psig (25 barg)
• Extensive choice of hygienic process connections
• Small dead zone and beam angle for small and narrow tanks
• Flush-mounted PEEK Lens antenna: CIP/SIP suitable
• 3 Year Warranty

NON-CONTACT LEVEL MEASUREMENT

FMCW radar transmitters enable continuous, contactless level measurement of liquids, pastes, granulates, powders, and other solids across a wide range of industries. 

DR3500 Industries:

• Pharmaceutical
• Biotech
• Biopharma
• Food & Beverage

For more information in New England, contact PSI Controls / Piping Specialties. Call 800-223-1468 or visit https://psi-team.com.

Replace Inaccurate and High Maintenance Displacer Level Controls With RF Admittance Technology

 Cost Effective Alternative to Displacer Level Measurements

THE PROBLEM

• Displacer accuracy is dependent on the specific gravity of a fluid. Varying specific gravities and “off spec” product result in significant measurement errors.
• Coating build-up on the displacer body produces errors.
• “Blowdowns” to clean displacer internals and cages is time consuming and expensive.
• Rebuilds due to component wear add significantly to the total cost of ownership.
• Interface measurements are more sensitive to slight specific gravity variances and result in separator throughput lower than the design specification.

THE SOLUTION

• AMETEK Drexelbrook Radio Frequency (RF) Admittance technology eliminates all of the inherent problems with Displacer technology level measurement.
• RF is immune to changes in specific gravity, density, temperature, and pressure.
• Accuracies to 1⁄4 inch of level in short span installations.
• No moving parts to wear, No periodic maintenance.
• Replacement cost differentials covered by eliminating one rebuild.

Piping Specialties / PSI Controls
https://psi-team.com
800-223-1468

The AMETEK Drexelbrook Impulse Guided Wave Radar Level Transmitter

The Drexelbrook Impulse is a guided wave radar (TDR) that measures all liquids and slurries' overall level and other volumetric measures. When competitive water sensors fail, the Impulse continues to provide accurate values. 

The Drexelbrook Impulse is a two-wire guided wave radar that uses field-proven TDR level (Time Domain Reflectometry) technology to produce accurate Total Level, Distance, and Volumetric outputs on all liquids and slurries. 

The Impulse handles even the most challenging level measuring applications. It will continue to give dependable and accurate measurements even in the presence of disturbances such as agitated or uneven surfaces, foam, or probe coating. Changes in the density and dielectric characteristics, dusts, mist, and turbulence do not affect it. When other water level sensors fail, the Impulse continues to measure. 

This water level sensor is a perfect replacement for costly mechanical dispenser systems, with a wide range of probe types and material possibilities for various applications. 

This guided wave radar is simple to use for any user due to its simple navigation, push-button setups, and HART connections. It only takes a few minutes to install. Choose your level measuring type and language, and the Impulse is ready to use. 

The Impulse guided wave radar is intrinsically safe, explosion-proof, and non-incendive, and it does not require calibration or level changes.

Additionally, Drexelbrook recently introduced an enlarged coaxial sensor for The Impulse GWR. The new 1.66" (42mm) diameter probe provides reliable accuracy within high viscosity liquids. The new enlarged coaxial sensor option for The Impulse GWR allows the material to flow off the sensor easily when used with viscous fluids.

Piping Specialties / PSI Controls
https://psi-team.com
800-223-1468

Drexelbrook CheckWell™ Water Well Level Sensor

The Drexelbrook CheckWell™ water well level sensor automatically monitors the level or drawdown in water wells up to 3000 feet deep.

The AMETEK Drexelbrook CheckWell™ water well level sensor automatically monitors the level or drawdown in water wells up to 3000 feet (914m) deep. It generates a continuous linear output signal that is directly proportional to the well level. This output can be used for remote monitoring/recording, warning signals, and pump control via optional current-actuated relays.

The advantages include quick installation, no manual maintenance, and an all-electronic design for exceptional reliability. Density variations, mineral or oil deposits on the sensing feature, and oil on top of the water do not affect the device.

DOWNLOAD THE DATASHEET HERE

Piping Specialties / PSI Controls

https://psi-team.com

800-223-1468

Level Measurement Solutions for Water Treatment

Several functional level measurement technologies have viable solutions for a broad range of industrial and municipal water treatment applications. Because of the variety of applications that exist and the varying application conditions, no one technology is best suited in all cases. 

POINT LEVEL VERSUS CONTINUOUS LEVEL INSTRUMENTS

Regardless of the application, there are two significant classifications of level measurement instrumentation: point level and continuous level measurement.

Point Level (On/Off) measurement indicates the absence or presence of level at a certain threshold (point) within a vessel.  Point-level switches perform as high level and spill prevention alarms, low level, pump protection alarms and pump control.

Continuous Level (Proportional) measurement indicates the level in a vessel over the full span of capacity.  These devices perform as process control as well as inventory control and management.

LEVEL CONTROL TECHNOLOGY CHOICES

The technologies used to measure level are affected differently by the varying process conditions. Below is a brief description of the different technologies commonly used in a water treatment facility.

RF ADMITTANCE/CAPACITANCE
RF Admittance/Capacitance employs a radio frequency signal and monitors for a change in capacitance. Either the presence or absence of material or how much material is in contact with the sensor, making it highly versatile and a right choice for a wide range of conditions and materials for point or continuous level measurement.

RADAR
Radar utilizes either Pulsed Wave or Frequency Modulated Continuous Wave (FMCW) through-air transmission that allows for an accurate non-contact reading of reflected electromagnetic signals.

MAGNETOSTRICTIVE
Magnetostrictive uses an electric pulse from ferromagnetic wire to accurately detect a float's position with embedded magnets.  As the pulse intersects the float's magnetic field, a second pulse reflects an electric circuit that accurately determines the distance and thus the level position.

CONDUCTIVITY SWITCHES
Conductivity switches measure the drop-in resistance when a conductive liquid contacts with two probes or a probe and a vessel wall.

ULTRASONIC (POINT LEVEL)
Ultrasonic (Point Level) measurement electronically resonates a crystal at a fixed frequency to generate sound waves that travel across an air gap to a second crystal.  As liquid fills the gap between the two crystals, the second crystal begins to resonate with the first.

ULTRASONIC (CONTINUOUS LEVEL)
Ultrasonic (Continuous Level) measurement uses a transmitter to generate an ultrasonic pulse and measures the time it takes for a reflected signal to return to the transducer to determine a liquid level.

GUIDED WAVE RADAR (GWR)
Guided Wave Radar (GWR) utilizes a Time Domain Reflectometry (TDR) technique by sending a highly focused electronic signal down a metallic rod or flexible cable waveguide. When the transmitted signal intersects the liquid's surface, it reflects along the rod or cable to determine the distance traveled. The level position is then easily inferred.

HYDROSTATIC
Hydrostatic measurement immerses a pressure transmitter with a sensing diaphragm and a sealed electronic circuitry that transmits an analog signal proportional to the liquid level above the sensor.

FLOAT SWITCHES
Float switches rely on a low-density float mounted in a vessel that magnetically couples to a limit switch. A change in fluid height actuates a switch by moving the float.

VIBRATION/TUNING FORK
The Vibration/Tuning fork is piezoelectrically energized and vibrates at a frequency of approximately 1200Hz, and as the process media cover the fork, the frequency shifts. The internal oscillator the frequency shift by and converts it into a switching command.

POINT LEVEL SOLUTIONS

Advanced RF Admittance/Capacitance point level devices are the most versatile of the point level technologies, especially with process media that can coat the sensor. They provide excellent spill/overfill protection. They are simple to install and have no moving parts, making them virtually maintenance-free. Their robust design and circuitry make them an ideal solution for many water treatment applications.

Both tuning forks and ultrasonic gap switches provide reliable high- or low-level measurements in various applications. For non-coating conductive liquids, conductivity switches provide economic priced measurement while float switches appear in many basic applications at very cost-effective prices.

CONTINUOUS LEVEL SOLUTIONS

Mechanical systems such as floats and bubblers require extensive maintenance and are less reliable and accurate than electronic systems. Hydrostatic systems afford better reliability and are simple to use, and can transmit data to another receiver for remote monitoring, recording, and control.

RF Admittance/Capacitance level is a time-proven and one of the best available technologies for indication and control. RF technology inherently provides the highest accuracy and repeatability in interface measurements. Variations in the makeup of upper and lower phases of a liquid have no appreciable effect on system accuracy. Recalibration is not required.

For short-span measurements, RF Admittance technology provides one of the most preferred readings. As the level of measurement span decreases, the more appropriate RF technology becomes. In spans of only a few inches, RF systems can repeatedly produce accuracies of 1/32ths of an inch. RF has the added benefit of not being limited by “dead zones” inherent with many popular technologies often selected for measurement ranges larger than 5 feet.

Non-metallic tanks pose no technical problems for Ultrasonic, Magnetostrictive, Hydrostatic Pressure, Radar, and GWR (Guided Wave Radar) technologies. The GWR approach is suitable for vessels with internal obstructions and uses lower energy levels than airborne radar technologies. Non-contact technologies, such as Radar and Ultrasonic, can have measurement ranges up to 130 feet. 

For long-range measurements or headroom limitations, flexible sensors offer insertion lengths up to several hundred feet for Hydrostatic Pressure and RF Admittance technology products. Loop-powered GWR (TDR)-based products allow measurement ranges up to 115 feet in selected applications. Magnetostrictive technology provides an accuracy of 0.1% of measurement span in flexible sensor designs up to a maximum range of 70 feet.

Piping Specialties / PSI Controls

https://psi-team.com

800-223-1468

Level Measurement for Water in Sewage Pools

This application takes place at a large power plant well known for its "Green Approach" and it's commitment to ensuring a clean and healthy atmosphere in and around the plant. 

The branched sewer system of the power plant requires instant maintenance and control. The plant uses water to operate the turbine. This water and other wastes move to the city’s wastewater treatment plant through the sewage system.

Some of the sewers are dispersed in remote locations around the plant, making it difficult for personal maintenance personnel to approach and repair damage on time. Plant technicians were looking for a solution to control the sewers better and avoid cases where wastewater might overflow. 

The sewage pool readings had to be transmitted to the central DCS because the sewage system connects to a central control room. The plant needed a 24/7 watch and an on-site guard to gain maximum control over those sewers. 

Technicians also stressed that wastewater flooding was inevitable because it takes time for the equipment to handle blockages. This flooding has caused severe damage to the environment. It was essential to control the wastewater level in the sewers to avoid cases such as these from reappearing. 

The Drexelbrook Usonic - The Solution 

After a lengthy examination of several possibilities, the plant decided to install two Drexelbrook USonic systems in its sewage pools. The ability of USonic to produce non-contact, continuous, and accurate readings of the water level in the pools gave the engineers of the plant a clear picture of the pools' status. 

Its compact size and integral construction simplify its installation, offering an efficient solution in no time at all. The USonic had no problem providing 12ft water level readings with a measurement range of up to 30 ft.  It can map obstacles in the pool and memorize interfering signals with its scan distance function. 

The USonic was linked to the central control system via 4-20mA, allowing the plant engineers to control the water level in the sewers constantly. The engineers know that the sewers would maintain the correct water level, and the system would be alerted in an emergency. 

Summary

The two USonic systems installed in the power plant give complete control over the sewers' water level to the plant's engineers. The systems' ability to display continuous level readings around the clock improved maintenance crews handle the sewage system.

To detect sudden blockages and avoid environmental damage on time, they can now save time. The plant received an immediate return on investment due to its compact size and reduced price.

Piping Specialties / PSI Controls

https://psi-team.com

800-223-1468

Cost-effective, Non-contact Ultrasonic Level Measurement from Drexelbrook

Affordable, 2-Wire Level Transmitter with the performance and features of premium, line-powered systems.

DOWNLOAD THE USONIC DATA SHEET HERE

USonics ultrasonic technology level products from the Drexelbrook family offers a cost-effective two-wire and line powered versions for the non-contact measurement of liquids and slurries for level, distance, volume, and open channel flow.   Level, size, volume, and open-channel flow measurements are easily configured via a menu-driven display.   The USonic level transmitter has a 4-20 mA two-wire HART output signal and is suitable for all Class I Div. 1, Zone, I.S., or explosion-proof locations.

For more information contact PSI Controls / Piping Specialties by calling 800-223-1468 or visit https://psi-team.com.

Radar Level Measurement: Comparison of 24 GHz and 80 GHz

Radar level transmitters are among the most accurate technology choices for process level and storage tank applications for continuous level measurement under demanding conditions.  These transmitters utilize Frequency Modulated Continuous Wave (FMCW) technology that offers superior signal processing capabilities and more reliable measurement than other techniques. The state-of-the-art signal processing capabilities of these transmitters, along with their frequency range, helps to ensure optimum application coverage.

24 GHz radar transmitters cover a broad range of applications, including liquids & solids. 

80 GHz radar transmitters are especially beneficial for level measurements in narrow tanks with internal obstructions due to their small beam angle.

This video, courtesy of AMETEK Drexelbrook, demonstrates many of the other differences between 24 GHz and 80 GHz models of radar level transmitters.

For more information on radar level transmitters in New England, contact PSI Controls (Piping Specialties, Inc.). Call them at 800-223-1468 or visit their website at https://psi-team.com.

Wiring the AMETEK Drexelbrook Universal IV RF Admittance/Capacitance Continuous Level Measurement System

The video above describes how to wire the Drexelbrook Universal IV  Continuous Level Measurement System.

The Universal IV level system is the most advanced RF continuous level measurement system available. It includes worldwide hazardous location approval and is immune to vapor, dust and foam interference as well as to tank obstructions such as nozzles, ladders, pipes and agitators. The Universal IV features standard display/keypad, auto-ranging capabilities, local or remote installation, as well as state of the art measurement technology providing unmatched stability and accuracy. It is ideal for a wide array of level applications in industries such as oil and gas refining, water and wastewater along with the pharmaceutical and biotech industries.

The Pro Model integrates the RF Admittance technology with the versatility of Cote-Shield technology.  The Cote-Shield technology is designed to ignore coatings on the probe and measurement span of 1" to 800'. 

The Lite Model is the entry level RF Capacitance measurement system without Cote-Shield capabilities, can be used in non-coating conductive liquids and insulated coating applications where Cote-Shield is not required and offers a level measurement range up to 20' typically.

Universal IV RF Continuous Level Measurement System Features

• Easy one-time calibration
• Low cost of ownership, no maintenance and no moving parts to wear out
• Immune to tank obstructions such as nozzles, ladders, pipes and agitators
• Available as intrinsically safe systems
• Output: 4-20 mAdc, HART. Compatible with HART.
• Supply voltage: 13-30 VDC, 2 wire loop powered

For more information on the AMETEK Drexelbrook Universal IV RF Admittance/Capacitance Continuous Level Measurement System visit this link - https://psi-team.com/drexelbrook-universal/ or call 800-223-1468.

FMCW (Frequency Modulated Continuous Wave) Open Air Radar Level Measurement

Non-contact level measurement using radar transmitters for the continuous, contactless level measurement of liquids, pastes, granulates, powders and other solids in a wide variety of industries.

OPERATING PRINCIPLE

• The radar principle used is FMCW (Frequency Modulated Continuous Wave). The FMCW radar emits a high frequency signal whose frequency increases linearly during the measurement phase (called the frequency sweep). 
• The signal is emitted via an antenna, reflected off the product surface and received with a time delay, t. 
• Time delay, t=2d/c, where d is the distance to the product surface and c is the speed of light in the gas above the product. 
• For further signal processing the difference Δf is calculated from the actual transmitted frequency and the received frequency. 
• The difference is directly proportional to the distance.
• A large frequency difference corresponds to a large distance and vice versa. 
• The frequency difference f is transformed via a Fast Fourier Transformation (FFT) into a frequency spectrum and then the distance is calculated from the spectrum.
• The level results from the difference between the tank height and the measured distance.

Learn more about this technology by downloading the Drexelbrook DR Series brochure from this PSI web page.

For additional information, call Piping Specialties, PSI Controls at 800-223-1468 or visit their web site at https://psi-team.com.

Setting Up and Calibrating the Drexelbrook MultiPoint II Level Switch

This video demonstrates how to calibrate and set the Drexelbrook MultiPoint II level switch.

The Drexelbrook Multipoint II level switch product offers three control points located anywhere along a single vertically inserted level sensing element. This level switch can be used to provide high level, high-high level, and low level control points. It also provides an adjustable differential feature for one of the control points for pump on/pump off control making it ideal for sump level control. It is designed to be intrinsically safe for Class I Groups A,B,C,D and Class II Groups E,F,G (Div. 1 and 2). The unit is mounted in FM approved explosion proof housing. The MultiPoint II has no moving parts and the need for maintenance is therefore eliminated. The Drexelbrook MultiPoint II is an economical solution for processes requiring multiple operating points.

For more information about level instrumentation, contact Piping Specialties, Inc. / PSI Controls by calling 800-223-1468 or visit their web site at https://psi-team.com.