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Quick-Connect Process Connection for RF Capacitance Silo Level Sensor

 


Quick-Connect Process Connection Probe
(Shown with Optional Clamp, Gasket and Ferrule)

 

Monitor Technologies’ TrueCap^® Model MK-2 RF Capacitance point level sensor is available with a “quick-connect” tri-clamp process connection that provides easy installation and removal of the unit for cleaning purposes. This connection has no exposed threads and offers an affordable solution for basic sanitation situations not requiring 3A rating. The “quick-connect” tri-clamp is available for the Ryton® and Nylon (food grade) versions of the standard and stub probes. Also, it can accommodate both a 1” and 1-1/2” ferrule size.

The TrueCap^® Model MK-2 RF Capacitance point level sensor is designed to provide a superior and stable sensitivity threshold making it suitable for a variety of powder and bulk solids, liquid and slurry applications. Advanced features of the Model MK-2 include automatic immunity to material build-up on the probe by its driven shield design, push-button calibration, enhanced temperature compensation and maximized reliability via smart sensing algorithms like “self-validating” fail-safe protection.

Please visit http://www.monitortech.com/product_p_rf2.shtml or call 1-630-365-9403 for more information.

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Silo Patrol provides level measurement for solid / liquid interface applications

Silo Patrol® provides level measurement for solid / liquid interface applications

  The Silo Patrol^® plumb bob “smart” level sensor from Monitor Technologies can be equipped with an optional stainless steel interface style plumb bob in order to provide continuous level measurement for settled solids in a blanket of water. The interface style plumb bob will penetrate through the water, make contact with the surface of the solid material and then retract to provide a level measurement. Examples of material applications that have been successful include sand, salt, corn, rice, potatoes and similar items that are covered by a layer of water. Interface with other liquids besides water may also be possible. Please check with Monitor regarding specific applications.

The SiloPatrol uses time-proven weight and cable techniques and combines Hall Effect sensor technology, state-of-the-art sealed bi-directional optical sensing, a split-compartment enclosure design, isolated outputs, SMT (surface mount electronic technology) and other valuable features to produce a rugged, reliable and accurate measuring system designed for the harshest and most dynamic conditions. In addition, a variety of operator interface devices and software, like SiloTrack software, are available to calculate and display material level inventory data.

Please visit www.monitortech.com for more details.

Alarm for Backed-Up Conveyor Chute of Powder or Pulverized Coal

Monitor's Binatrol® diaphragm-style level switch is a reliable and cost-effective way to detect levels of powder and bulk solids in storage bins, silos and other vessels. In addition to level indication, the Binatrol® diaphragm switch can be used to detect plugged or backed-up conveyor chutes for some applications. For example, we have several companies that install diaphragm switches with the optional Hycar® covers to be used as alarms for backed-up conveyors of powder or pulverized coal chutes that provide feedstock to boilers.

The Hycar® (rubber nitrile) optional cover is designed to provide the Binatrol® Model G/GX series diaphragm bin level switch with additional durability for use with more abrasive dry materials like powder or pulverized coal. See image below.

The Binatrol® is a surface mounted, minimally intrusive switch that makes it ideal for vessels or chutes limited in size or internal clearance. Also, the Binatrol diaphragm switch requires no input power.

For more details please visit www.monitortech.com, e-mail [email protected] or call 1-630-365-9403.

Vibratory Level Sensor and Heavier Dry Materials

        


Recently one of our Application Engineers was asked if a vibratory style level sensor could be used to detect heavier bulk solids materials such as metal shot blast media.

Our Application Engineer responded by mentioning that a vibratory type level detector can indeed be used to detect shot media.  However, due to the nature of the vibratory technology, this type of sensor would require a protective baffle to be installed if it is employed where heavier materials are stored or in a dynamic process where the material may be shifting en mass (see baffle examples above). Most designs for the vibratory type level detectors contain a sensing element, that if bent as a result of mishandling or exposure to excessive process dynamics the sensor can be rendered ineffective.  Of course, the heavier the target media the greater the chance of the sensing probe suffering damage.

Heavier powder & bulk solids materials like metal shot blasting media may be even better served by a bin level indicator which is more rugged.  Monitor's model MK-2 R.F. Capacitance level detector is recommended.  This instrument is designed with a sensing probe constructed of a solid T316 SS and even if deflected will continue operating.  It is very rugged.

 

For more detailed information on the best application uses for vibratory sensors, please check out our blog entitled How Many Figs does it take to Equal 150 Newtons?

Flexar® can provide dependable continuous level sensing in the production of activated carbon

 
Figure 1


Figure 2

Activated carbon, also known as activated charcoal, is a carbon product that has been put through a process to make it very porous. It is then used in the purification of air and water, the cleanup of environmental spills and the capturing of volatile compounds. For example, activated carbon is used in mercury emission control systems for coal-fired power plants. Activated carbon can be derived from a variety of raw materials including coal, lignite, coconut shells, nutshells, wood and other agricultural by-products. The Flexar® guided wave radar level sensor (see Figure 1) has been used to provide continuous inventory management for most of these raw materials. The Flexar has also been used to control inventory on the finished forms of activated carbon such as granular, pelletized, and powdered states. Figure 2 shows an original material (nutshells) on the left and the activated carbon product that is made on the right. Flexar sensors were chosen to provide real-time continuous level control in the storage for both of these items. Flexar is very versatile because it is unaffected by dust, bulk density, temperature and other properties. It can also be used for a variety of liquid applications.

Monitor Technologies’ Flexar^® guided wave radar sensor is a continuous level measurement system using TDR (time domain reflectometry) principles where radar pulses are focused down to the material surface by the unit's wave guide (a heavy duty cable) and the time-of-flight of the pulse reflection back to the instrument electronics is directly related to the empty distance in the vessel and the material level.

Benefits of Flexar^® include no moving parts for less wear and tear, easy installation and setup with minimal to no field calibration required, a universal power supply for high or low voltage options and a choice of RS-485 or analog 4-20mA output. It can also be interfaced with the SiloTrack inventory management software. For more details on Flexar guided wave radar please visit www.flexar.info

 

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Auxiliary Output Enclosure (AOE) Satisfies Input Needs for other Plant Systems

  

When choosing a continuous level measurement system, in addition to an operator interface, sometimes a customer also wants to have an output to some other type of control system such as a PLC or DCS. Available outputs include both relay contacts and analog outputs.  To fulfill these requirements, Monitor developed an auxiliary output enclosure (AOE) capable of housing as many as four output cards containing either relay outputs, analog outputs or a combination of both. When controlled by our HMI2 operator interface, each SiloPatrol® SMUse level sensor can drive one analog and up to two relay outputs. If SiloTrack Inventory Management Software is the operator interface, the number of analog outputs assignable remains at one analog output per sensor but there can be up to four relay outputs per sensor. RS-485 communication wiring consists of a twisted pair that is shielded and installed in a daisy chain fashion. Since the auxiliary output enclosure is also an RS-485 driven device, the AOE can be placed anywhere along the RS-485 communication network. Placement of the AOE in close proximity to a PLC or DCS reduces the amount of additional wiring necessary to connect the AOE outputs to the inputs of these other devices. This will significantly reduce the amount of interface wiring that would normally be required by standard analog output sensor wiring practices.

Flexar® guided wave radar level sensors that are used in conjunction with SiloTrack Inventory Management Software can also drive an auxiliary output enclosure as previously described.

Auxiliary output enclosures are available in either two or four output card configurations. (Two card version shown above.)  The two types of output cards can be mixed or matched. Flexar® guided wave radar and SiloPatrol® SMUse sensors may not currently coexist on the same RS-485 communication network. Consult Monitor's Technical Support group for selection of the correct SiloTrack product offering if your over-all sensor system design requires the use of both SiloPatrol SMUse and Flexar guided wave radar sensors.

Technorati Tags: level sensor level measurement bin level indicator level control solids level indicator

The day the sky darkened...a broken bag detector story

                   

The following diatribe or rant is a dramatization, the names have been changed to protect the innocent...

Friday started off as any other day, only a bit better than most days because it was a Friday!  Things at the plant had been running smooth, business seemed to be improving and we all hoped "free parking" in the company lot would soon be reinstated. Three dollars a day to park in the company lot seemed fair at first but after a while it all adds up!

All systems were purring along, in fact things were going well, perhaps too well.  Many routine maintenance "tasks" had been put on the back burner due to some staff reductions.  Sadly one of the easiest PM chores to ignore had to do with checking the filters in our baghouse.  No one ever really wants to climb up on the roof unless of course it is July 4th!

Little did we know that a small tear had began in one of the bag filters. Steadily the bag filter leak grew larger and larger allowing more dust to escape from the broken bag.  The weakened bag filter continued to fail, more dust was escaping. It was almost as if the dust wanted to run away from the bag house that had held it captive.

Suddenly a failure of catastrophic proportion occurred, a domino effect caused by air flow, dust, and failing bags, raged through the baghouse.  Only one small bag remained intact to prevent all of the dust from exploding into the atmosphere. Quickly, under the extraordinary amount of pressure and debris, the last bag filter gave way.  A cloud of dust roared from the bag house in a menacing swirl of darkness, temporarily darkening the sky over the "pay to park" company lot.

Alright, I am no Stephen King...but a situation like this could occur if you have a filter failure in a baghouse.  One of the best ways to monitor particulate emissions is to install a simple device designed to detect broken bags in a dust collector before a catastrophic failure occurs. 

Monitor offers a product we call the DustAlarm.  The DustAlarm is a broken bag detector, or a triboelectric particle emission monitor, the DustAlarm is designed to notify you when the amount of dust in the air flow begins to increase due to a pending filter failure.

The DustAlarm broken bag detector provides reliable and economical detection of leaks and filter failures in many powder and bulk solid industries.  As mentioned, the DustAlarm is a triboelectric particle emission monitor.  Triboelectric measurement has been used for years for broken bag detection, the phenomenon, also called "particle impingement" or "frictional electrification" pertains to the resulting charge transfer when one material rubs or impacts another.  The result of a dust particle collision with a stainless steel probe is the generation of electrical signals which are continuously monitored and analyzed by the electronics.  When the signal exceeds a preset level (such as what occurs when a bag begins to fail), a time delay is initialized.  If the signal remains above the preset level for the duration of the delay, alarm relay outputs are "energized".  These relays can be used to go to an alarm or to shut down your system to allow you to inspect your bag filters and determine which filter is beginning to fail.

For more information on the DustAlarm please refer to sales bulletin # 723.  If you have any questions concerning your application please give us a call.  One of our application engineers can work with you to make sure that the DustAlarm will help prevent the sky's above you from growing dark!

Best regards,

Scott Bonine

Director of Sales

Affordable Bin Aeration-You can leave the hammer at home!

Have you ever looked near the discharge area of a silo or hopper?  Have you ever noticed how banged up this area often looks? Have you ever seen a hammer located nearby? My guess is that we have all seen evidence where someone has severely beat the discharge area of a silo or hopper with a large blunt object to help empty the silo. Admittedly, I enjoy beating things with a hammer as much as the next guy but I would prefer to keep this hobby reserved for home "repair" projects.

In addition to several different types of remarkable level controls, Monitor also offers products to help fluidize materials so they will discharge freely from the vessel.  One of the most popular items we provide to assist in the flow of dry bulk powders from storage vessels is the rectangular air pad. The air pad operates by introducing air into the body of dry powder, this action fluidizes the material once it has "settled" after the target material was initially conveyed into the vessel. For best results multiple rows of air pads are often used depending on the vessel size and the bulk density of the target material  The number of rows and quantities will differ by each application.  One of our application engineers can assist by recommending a possible air pad solution for your specific material flow problem.

Air pads are very affordable and simple to install, different materials of construction and diffuser material are available depending on the application. The Monitor air pad can easily install in existing cut outs of other brands. Air supply requirements are minimal, typically 3-5 PSI.

Please give us a call to discuss your application, typical applications include but are not limited to:

• CEMENT  
• FLY ASH
• CARBON BLACK
• BENTONITE
• LIME
• GYPSUM
• FLOUR

We look forward to hearing from you.

Best regards,

Scott Bonine
Director of Sales
www.monitortech.com

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All the Leaves are Brown, and the Sky is Gray above your Silo Level Indicators....

So here I am reminiscing about a birthday celebration I attended last night and The Mamas and the Papas jumped in my head as I flashed back to the 60's and 70's for a minute or two. One of our staff cruised by my office door with a used sensor over his shoulder that was in need of evaluation. Since I like examining equipment that has been working in the field for extended periods of time, I  got up and followed it to the test area where we examined the unit. It was a SiloPatrol SMU that was produced in 2004. Upon removal of the cover, a small amount of white powder spilled out on the bench. After seeing the powder and knowing the SMU was sent in because of a Motion Error, we directed our attention to the wiper seal and discovered that it was packed hard in gypsum powder to the extent that the 3/16" SS cable could not travel freely through the wiper. So, finding out what I wanted to know was accomplished I then returned to my desk. "What does this have to do with dead leaves and a dark Autumn sky?", you ask. It got me thinking about a similar unit I worked on a couple of years ago in the dead of winter with 22 knot winds and temperatures in the high minus teens. If the maintenance staff at that facility had performed a preventative maintenance inspection in November, I probably would not have been getting frostbitten fingers in January. (It is difficult to thread a 3/16" SS cable and a compression sleeve and thimble with heavy gloves on.) So to conclude, If you are the proud owner of any brand of plumb bob style continuous level sensor, you might want to think of getting someone aloft to check everything out before the snow flies. And if you live where it is hot by 10AM, you still might want to pull a PM to check for worn parts so you can order them and change them out before your system actually breaks down. I almost forgot to mention that we do have part kits to allow the owners of our original SMU design to convert over to the new wiper seal compartment that eliminates the necessity of cutting your cable to change out a worn out or clogged wiper seal.

Greg DeRudder
Product Manager
[email protected]

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Avoid Obstructions When Installing A Guided Wave Radar Sensor

Guided wave radar instruments, like Flexar®, use a cable as a wave guide or antenna.  The microwave energy pulses down the cable antenna and reflects off the material surface.  The reflected pulse travels back up the antenna to the transceiver. 
Obstructions near (within ~12”) of the cable antenna have a high probability of interfering with the microwave energy measurement pulses. Just think of attempting to make a cell phone call while standing inside a metal doorway.  Sometimes it works but most times it doesn’t.
Some obstructions result in crazy reflective echoes.  These reflections can exceed the strength of that from the material surface.  To cancel such large reflection an irritating and often substantial dead zone has to be created along the length of the wave guide cable antenna.  Not good.

Obstructions also cause signal degradation.  Like the cell phone example, energy from the wave guide cable can be bleed off onto the obstruction.  Because the Flexar guided wave radar sensor is measuring and not cooking the silo contents the emitted energy level is rather limited.  If enough of this energy is bleed off there is a possibility that insufficient energy will remain to make a viable reflection.

Vessel View, Exterior

Vessel View, Interior

 

   

Pictured above is one of the most common examples when it comes to interfering obstructions.

For unknown reasons the factory provided application and mounting recommendations were disregarded and the Flexar instrument was mounted to the pictured stub nozzle.  Under the best of circumstances the height of a stub nozzle should not exceed the inside diameter.  In this example that guideline has been completely violated. As shown, the nozzle protruding above and below the roof line well exceed the inside diameter.  This resulted in crazy pulse reflections which were so strong that the level signal would not follow the
material level.  The short term solution required a six foot dead zone to be created on the top portion of the vessel. 
This meant the customer lost the ability to monitor the material in the upper six foot section of the vessel.  Not good. 

The long term solution is to move the Flexar to the  center of the forward plate which sits atop a large nozzle which better conforms to the mounting guideline.

Andy

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