Magnetic Liquid Level Gauges

Magnetic level indicator with supplemental
guided wave radar instrument
Gemini Model - Magnetrol

Magnetic liquid level gauges are an excellent alternative to sight glass level gauges for many process measurement applications. Their reliable performance and adaptability has made them the primary choice in a wide variety of industrial settings.

Essentially, a magnetic level gauge or magnetic level indicator, is a sight glass with enhancements that provide better readability and a form factor that enables the inclusion of additional level monitoring functions on the same device. Where a sight glass requires operator proximity to read liquid level, the magnetic level gauge's indicating scale, or flags, can be clearly viewed from a considerable distance. A sight glass gauge can also be hindered by difficulties in visually determining liquid level because of deterioration of the glass surface or properties of the liquid. Magnetic level gauges remove the need to observe the liquid directly by incorporating a float device within a tube connected to the liquid containing vessel. As the float moves in response to liquid level changes, its magnet causes the indicator flags on the scale to rotate and display either a black face to indicate no liquid present, or a colored face.

Magnetic level indicators are available with numerous options, including armored casings to protect the tube and float arrangement and limit switches to signal the attainment of specific level conditions. Combining a MLI with another level measurement technology, such as guided wave radar or magnetostrictive, can provide an analog process signal representing liquid level and serve as a redundant measuring device for critical applications.

The document included below provides illustrated detail about the devices and their proper application. Share your process measurement requirements and challenges with instrumentation experts. The combination of your process knowledge and their product application expertise will produce effective solutions.

Magnetrol Orion Magnetic Liquid Level Indicators from Miller Energy, Inc.

Ultrasonic Contact Level Switches Provide Reliable Overfill Protection

Echotel® Ultrasonic Level Switches

Magnetrol

Requirements for safety regulation compliance continue to grow. Business operators want increased levels of risk aversion and contingency management. In industrial settings where fluids are processed or stored, meeting these goals calls for new layers of protection and redundancy for existing layers.

Tank overfill is a serious concern of any fluid processor. Providing multiple methods of measuring tank or vessel fluid level provides substantially greater assurance against overfill. One scheme involves using a continuous level measurement instrument, such as guided wave radar, to provide the real time tank level signal and an ultrasonic level switch as a tank overfill indicator.

The operating principal of an ultrasonic level switch is quite simple. A transducer sends an ultrasonic pulse across a gap. When liquid media is present in the gap, the sound wave is transmitted with little attenuation across the gap and detected. When liquid media does not fill the gap, the sound wave is strongly attenuated and fails to transmit across the gap.

Tuning fork level switches are commonly applied as the overfill detection device, but Magnetrol, a recognized global innovator in level measurement, feels they have a better solution with their Echotel® ultrasonic level switches. The video below provides an illustration of how the ultrasonic level switches can be applied, as well as a comparison between ultrasonic and tuning fork methods.

Share your level measurement requirements and challenges with a product application specialist. The combination of your process expertise and their product application skill will produce an effective solution.

Thermal Dispersion Flow Meter For Compressed Air and Nitrogen Measurement

Thermal Dispersion Flow Meter
Magnetrol

Monitoring compressed air usage in a factory or other operation where it is consumed is essential for proper system maintenance and attainment of energy efficiency goals. The ability to track down leaks and monitor compressed air usage enables stakeholders to work toward maximizing the return on an asset with substantial initial and operating costs.

Easy installation and simplicity of operation are advantages for any instrument applied in this manner, making compressed air flow measurement a good application for a thermal dispersion flow meter. With no moving parts and a simple operating principal, a thermal dispersion flow meter can be quickly installed and put into operation. A digital display of the flow measurement provides local information, and a networking connection or other signal output can provide for remote or centralized monitoring and data collection.

A cut sheet is included below that provides detail on technological, operational, and installation aspects of this simple and effective instrument. Share your flow measurement challenges with application experts, combining your own process knowledge with their product application expertise to develop cost effective solutions.

Thermal Dispersion Mass Flow Measurement from Miller Energy, Inc.

Low Cost Radar Level Transmitter For Industrial Process Applications

Magnetrol Model R82 Radar Level Transmitter

With its ability to reliably detect tank liquid surface level under conditions that prove challenging to other methods, radar technology generally provides an operational advantage over other non-contact level measurement options. Historically, the cost of radar level transmitters for industrial process control applications has hindered their success as a unit of choice for some installations. Magnetrol has changed that imbalance with their recent introduction of a lower cost radar level transmitter for tough applications.

The Model R82 provides radar performance at a price point comparable to competitive ultrasonic units, but maintains the performance advantage inherent in a radar based device. The unit utilizes pulse burst radar technology at 26 GHz, employing advanced signal processing to filter out false echos produced by a range of in-tank conditions that can produce false readings from ultrasonic units.

The short video below provides a closer look at the R82 and its performance advantages. Technical data sheets and any application assistance you may need is available from product specialists. Share your level measurement and control challenges with them and work toward the best solution.

New Product - Model R96 Non-Contact Radar Level Transmitter

New Model R96 Non-Contact Radar
Level Transmitter
Courtesy Magnetrol International

Magnetrol is a well known manufacturer of level and flow measurement instrumentation for the industrial process control field. The company recently released the Model R96 Non-Contact Radar Level Transmitter for applications where continuous fluid level measurement is required.

The company's description of the product...

"Virtually unaffected by the presence of vapors or air movement within a vessel’s free space, the two-wire, loop-powered, 6 GHz Radar transmitter measures a wide variety of liquid media in process conditions ranging from calm product surfaces and water-based media to turbulent surfaces and aggressive hydrocarbon media."

 The new product offers features that combine to make a state-of-art instrument for accurate continuous level measurement. A product brochure is included below. Contact application specialists to formulate the right product configuration for your level measurement challenge.

Non Contact Radar for Level Measurement and Control from Miller Energy, Inc.

Simple Field Verification of Thermal Mass Flow Meter Calibration

Magnetrol TA2 Thermatel
Thermal Mass Flow Transmitter
Courtesy Magnetrol

In processes that require mass flow measurement of gases or air, thermal dispersion measurement technology is often selected for use. Its direct mass flow measurement and other attributes make this technology a favorable alternative for many applications, including combustion air, compressed air, natural gas, aeration air, vent lines, biogas production, vent lines, hydrogen lines, and more.

Schematic depiction of dual
temperature sensors on a
thermal mass flow meter
Courtesy Magnetrol

As it name implies, a thermal mass flow meter calculates flow by using temperature measurements. Two temperature sensors are inserted into the flow path. One measures the media temperature, the other is heated by a measured power source. With a device factory calibrated for a specific medium, the amount of heat transferred away from the heated sensor can be known, and will be proportional to the mass flow rate of the medium.

Some of the key attributes of thermal mass flow measurement devices:

• Comparatively moderate initial cost
• Compatible with measurement of low density gases that cannot be achieved with some other methods
• Provides direct mass flow measurement
• Most devices have option for output of process temperature
• High turndown, with strong signal at low flow rates
• Field calibration verification

Verifying the proper operation of transmitters of any type can be challenging, especially if performed in the field. The video below demonstrates how the Magnetrol TA2, a thermal mass flow transmitter, can have a calibration verification performed on site with a simple procedure.

The video is short and concise, with some valuable technical knowledge to build your understanding of how this technology works. More detailed information about mass flow measurement, or the specific devices shown in the video, is available from a product application specialist. Share your process measurement and control challenges with them and collaborate to develop the best solution.

Magnetic Level Indicators - Knowledge Base and Selection Guide

Magnetic Level Indicators
Courtesy Orion Instruments

Industrial process control frequently involves the storage of liquid in vessels or tanks. Continuous and accurate indication of liquid level within the tank is an essential data point for safety and process management. While there are a number of methods and instrument types utilized to provide tank level measurement, the instrument of choice is often a magnetic level indicator, also referred to as a magnetic level gauge. Its use for providing level indication has a number of positive attributes:

• Construction that is resistant to breakage.

• Measuring indicators, switches, and transmitters mounted externally, without contacting the medium being measured.

• Maintenance free operation. No regular cleaning needed.

• Readable level indication from greater distance than glass sight gauges.

• Magnetic level indicators can accommodate greater fluid level ranges without the need for multiple instruments.

Orion Instruments, a Magnetrol company and industry leader, has produced a comprehensive guide to magnetic level gauges, switches, transmitters, and related products. It delivers experts and newcomers an understandable and clear description of the technology and principals of operation behind magnetic level gauges and instruments. The guide also assists the reader in properly specifying and selecting the best instrument configuration for an application. A table of contents at the front of the document helps readers to quickly find the information they need.

Take a couple minutes to roll through the document and you are likely to find new and useful application tips and product information. Any questions about magnetic level indicators or your process measurement and control applications can be clearly addressed by a product specialist.

Orion instruments magnetic level gauge & instrument selection guide from Miller Energy, Inc.

Guided Wave Radar for Hygienic Applications: Advantages Over Other Technologies

Guided Wave Radar
for Hygienic
Applications

Operating Principle

Guided wave radar is based upon the principle of TDR (time domain reflectometry). Pulses of electromagnetic energy travel via the waveguide. The pulse is reflected when it contacts a liquid surface and the distance is then calculated.

Guided wave radar transmitters are available with a 304 stainless steel housings designed specifically for use in hygienic applications. This instrument meets the needs and requirements for the wetted and non-wetted materials, process connections and surface finishes of hygienic industries.
Features

• Low dielectric measurement capability (εr >_ 1.4)
• Volumetric output
• Quick connect/disconnect probe coupling
• Operates in visible vapors and ignores most foams
• IS, XP, and Non-Incendive approvals
• Ignores coating buildup

Advantage Over Other Technologies

• Advantage over Differential / Hydrostatic Pressure Transmitter:  Replaced by Eclipse due to setpoint shifts, blockage, leakage, installation cost & long term calibration / maintenance

• Advantage over Magnetostrictive: Replaced by Eclipse due to setpoint shifts, turn-down and clean ability & long term calibration / maintenance.

• Advantage over RF Capacitance: Replaced by Eclipse due to dielectric shifts, coating issues & long term calibration / maintenance.

• Advantage over Load Cells: Eclipse is more cost effective and long term cost of ownership is lower due to long term calibration / maintenance.

• Advantage over Ultrasonic: Replaced by Eclipse due to vapors, condensation, temperature restrictions, foaming & turbulence.

• Advantage over Through Air Radar: Replaced by Eclipse due to performance issues on low dielectric media, short range measurement because of dead band issues in small vessels, measurement issues when using false echo rejection from internal obstructions such as agitators and spray balls, signal attenuation from turbulence, foam, condensation and spray from spray balls used during cleaning or product filling. Through air radar can have issues from variable false echoes generated when spray hits the antenna when vessel is filled from spray balls.

For more information see this Guided Wave Radar bulletin:

Guided Wave Radar Level Transmitter For Hygienic Applications from Miller Energy, Inc.