LED Illuminator for Flat Panel Water Gauges

LED Water Level Gage Illuminator
Courtesy Clark Reliance

Illuminators improve the visibility of flat panel water gages used for boiler water level monitoring. They serve as a backlight source that accentuates the display of the water-vapor line in the gage.

The DuraStar, from Clark-Reliance, can be fitted to
their flat glass panel level gages. The heatless LED illuminator is available in configurations for ordinary or hazardous classified locations. It provides high contrast visibility in all ambient lighting conditions, can be retrofitted to most existing gages, and is maintenance free.

Share your boiler trim instrumentation and control requirements and challenges with application specialists. Combine your process and facility knowledge with their application expertise to develop effective solutions.

LED Illuminator for Flat Glass Level Gages from CTi Controltech

Armored Liquid Level Gauges With Specialty Indicators

Armored liquid level gauges provide protection from
mechanical stress and impact
Courtesy Jerguson / Clark Reliance

Sight glass liquid level gauges are a mainstay of fluid processing operations that store raw materials, intermediate, or final product in tanks and other vessels. Having a direct visual indication of fluid level at the tank enhances safety and provides the all important data point about what is happening inside the tank.

These level gauges are installed on the exterior of the tank, exposed to whatever environmental or operational hazards existing or occurring at the location. Armored level gauges are appropriately named because of their construction. They are designed to resist impact and mechanical stress, as well as a range or environmental conditions.

There are generally two versions of armored level gauges, reflex and transparent. The names refer to way in which light is handled by the gauge to reveal the liquid level. One manufacturer of armored level gauges and other level instruments, Clark-Reliance, provides a good description of the two gauge types. Their brand of armored level gauges is Jerguson, and I provide their description here of the two types (source)

Jerguson® Reflex Level Gauges are ideal for clean total level indication applications for refining, petrochemical and general use applications. The reflex prisms are molded and polished to provide a crisp black-silver bi-color indication of the fluid level. As light passes into the reflex glass, if there is fluid present, the light continues through the glass and reflects off the back of the level gauge, providing a black color for fluid level regardless of the actual color properties of the process fluid. If fluid is not present, the light is reflected off the glass back towards the user, providing a shiny silver or mirror-like appearance to indicate vapor space.

Cross section of reflex level gauge 

Jerguson® Transparent Level Gauges are selected for interface level indication, dirty service or any application that requires the use of a shield to protect the glass from corrosion. A transparent gage is also known as a “thru-vision” gauge since the gauge is constructed with two pieces of flat polished glass assembled on opposite sides of the level gauge chamber. Since the user can see straight through the gauge, it is also easy to view the fluid properties, such as color, whereas this would not be possible with a reflex gauge. The use of an illuminator is always recommended on a transparent gauge.

Cross section of transparent level gauge

Selecting an armored level gauge is an exercise in preparing for known and unknown events that might disable your ability to directly read fluid level. Armored level gauges are employed extensively in chemical, petrochemical, and other industries where reliability under challenging conditions is essential. Wherever there are mechanical hazards, an armored level gauge may ultimately prove to be cheap insurance against downtime or delay.

Share your level measurement challenges with a product application specialist. Combine their product expertise with your process knowledge to produce an effective solution. Below is a data sheet for one of several series of Jerguson armored level gauges, so you can explore more detail. Contact the product application specialists for more information about larger sizes, higher vessel operating pressures, and optional configurations that will best suit your application.

Jerguson armored liquid level gage series 300 l from CTi Controltech

Specialty Transmitter Isolation Valve for Tanks and Vessels

Transmitter Isolation Valve
Courtesy PBM Valve Solutions

Fluid process control applications frequently employ tanks and vessels as part of the processing chain or for storage and holding. Level transmitters can be installed on the tank to provide indication of liquid level. While there are numerous combinations of fittings and valves that could be used to mount and connect the transmitter to the tank, one manufacturer has designed a specialized valve intended to mate a transmitter to a tank fitting with great advantage.

The specialized transmitter isolation valve minimizes dead space to prevent media residue buildup. It can be configured to accommodate CIP and drainage without process interruption. Calibration ports and industry standard mountings allow for broad application throughout the fluid process control industries.

A cut sheet is provided below, and more information and application assistance is available from process control specialists.

Specialized Transmitter Isolation Valve from CTi Controltech

Proper Way To Commission Jerguson Level Gage With Ballcheck Valves

A significant part of industrial process control is the proper commissioning and maintenance of the various physical components of the process. Doing things right, following proper procedures, is essential to establishing the proper equipment or instrument operating condition.

Level gauges with ballcheck valves are fairly common throughout industries that employ liquid storage tanks. The video below is produced by Jerguson, a recognized manufacturer of level gages, switches, and transmitters. Though it is specific for the manufacturer's product, seeing the interior workings of the valve and learning not only the proper procedure, but why the procedure is important, is useful knowledge for all stakeholders.

Product application specialists can provide additional information and help you meet your level gage challenges.

Liquid Level Measurement With Differential Pressure

Flange mount differential pressure transmitter
Courtesy Azbil North America

Industrial process operations frequently involve the use of liquid storage tanks for raw materials, in-process liquids, or finished product. Regardless of the tank usage, the data point indicating the liquid level in the tank is useful for effective process operation and safety.

Deriving tank liquid level can be accomplished utilizing a number of technologies, classed as direct or inferred. Direct level readings indicate level by interacting with the interface of the liquid surface and the unfilled area of the tank. A simple example of this would be a float, the position of which is read on a scale or transmitted to a controller. Inferential measurements are derived by directly measuring a condition which is affected in a predictable manner by the tank liquid level.

Differential pressure is an inferential methodology for determining liquid level. A differential pressure transmitter measures the total pressure of the fluid column and subtracts the pressure exerted on the surface of the liquid, delivering a signal indicating the net pressure exerted by the liquid column in the vessel. This value can be used to calculate the height of the liquid column, weight of the fluid, percentage of tank fill, or other useful values. The differential pressure method of liquid level measurement has some key features:

• Cost effective
• Limited moving parts in a complete installation, generally consisting of isolation valves for transmitter servicing
• Best applied to clean liquids with known uniform density
• Provides good accuracy over a wide operating range
• Easily mounted or retrofitted to vessel surfaces
• Low maintenance requirements
• Specifically designed seals can be utilized to provide hygienic vessel connections, or device protection from high temperature or corrosive process media

Like any measurement technology, the differential pressure method of liquid level measurement provides the best results when properly installed and maintained. There are numerous installation configurations and options to fulfill a wide variety of applications. A product application specialist can help you specify the best arrangement for your application.

Azbil Industrial Pressure Transmitters from CTi Controltech

Innovative Magnetic Level Gauge Provides Accurate Indication Under Adverse Conditions

Magnetic Level Gauge on Tank
Courtesy Jerguson

We, as engineers, industrial process operators and stakeholders, recognize the necessity and value of a continuous stream of accurate and timely information about our processes. Our experience has also taught us that the environment and activities surrounding our installations can have a significant impact upon our ability to continually gather accurate process measurements. Some of our concerns include:

• Weather - An element whose impact cannot be understated....or easily predicted.
• Physical Contact - Equipment and measurement devices must be protected from damaging impact.
• Security - Vandalism, cyber invasion, and other external threats are possible

Our responsibility, as operators of machines and handlers of materials that can produce hazardous or life threatening conditions in the case of failure or error, is to foresee every reasonably probable event that could adversely impact the safe and proper operation of our industrial processes.

One manufacturer has developed an innovative solution to a potential problem in the application of magnetic level controls.

The short video below outlines the source of the potential failure and the way in which the product design change successfully overcomes a potentially adverse impact on process measurement. Invest less than three minutes of your time to watch the video and build your application knowledge by learning from the experience of others. Do not hesitate to contact a product application specialist for more detail, or to discuss your process measurement needs.