Monitor Technologies, LLC
On The Level
June / July 2013
In This Issue
Practical Tip...Main Aspects to Consider When Selecting a Rotary Paddle Level Sensor
Product Spotlight...RF Capacitance Level Sensors with Time Delay Function
Word of the Month
Upcoming Holiday Schedule
Practical Tech Tip
Main aspects to consider when selecting a rotary paddle style level sensor 
SafePoint® Truly Fail-Safe Rotary Paddle Level Sensor With A Standard 3-Vane Paddle Assembly 
Rotary paddle level sensors are the most commonly used sensors for point level indication in powder & bulk solids applications. This is mainly due to their versatility in a variety of powder & bulk materials and reasonable price range. There are a number of styles out in the market to choose from, so how do you determine which one is best for your needs? Below are a few of the main factors to look at when selecting a rotary paddle level sensor:

> Application / Purpose - Rotary paddle level sensors work well as high-level, low-level and intermediate-level indicators for most powders, granules, pellets, aggregates and other bulk solid materials. If located properly, they can also be used for high level detection in dust collection hoppers and for plugged chute detection (more details on plugged chute).

How demanding the application is plays a big part in the type of rotary level sensor that is selected. For instance, "mini" rotary level switches are good for smaller bins/areas under light duty, low use conditions; However, if the level sensors are going to be used on a regular-basis or in critical applications, the standard version or fail-safe rotary paddle sensors would be recommended
Level Paddles
Examples of Paddle Assemblies 
(like Monitor's Model KA/KAX or SafePoint sensors).

> Paddle Assembly - In most cases you have a choice on the paddle assembly you can use. The paddle selected will help determine how successful the unit is for your specific target material. The major factors for picking a paddle assembly include: material density, material flow properties and sensor mounting location & method.  The standard 3-vane paddle is the most commonly used because it works for the widest range of target materials. "Insertable" paddles, such as a 1-vane scimitar or 2-vane collapsible paddle, are useful when fitting a paddle through a pre-existing 1-1/4" NPT or 1-1/2" BSPT coupling hole from the outside of a bin or silo.

Click here for Monitor's paddle selection chart (PDF file)
Click here for article on selecting a paddle assembly (in PBE magazine - PDF file)

> Fail-safe Option - In most cases for rotary paddle level indicators, "the term fail-safe refers to the output signal condition that occurs with loss of power to the switch". However, there are some fail-safe rotary level indicators, referred to as "truly fail-safe", "self-validating" or "fail-safe plus", that in essence also monitor their own ability to function. This self-analysis includes sensor health in addition to indication of a power failure.

Click here for article regarding fail-safe rotary paddle sensors (in PBS magazine)

More Information on SafePoint® "Truly" Fail-Safe Rotary Paddle Level Sensors:       

More Information on Model KA / KAX Standard Rotary Paddle Level Switches:


Product Spotlight

TrueCap RF Capacitance Level Sensors
TrueCap LED

TrueCap® RF Capacitance Level Sensors Provide Maximum Reliability with Time Delay Function

Monitor Technologies' TrueCap® RF capacitance point level sensors are designed to provide stable sensitivity and durability for powder and bulk solids applications, as well as, some liquid and slurry applications. In addition, the TrueCap has a settable function that provides a time delay from when the unit first enters a detect mode, to when the relay output is activated. This function helps to eliminate premature material-present indication that can sometimes occur during the filling process if material was to intermittently come in contact with the level probe.

Other features of the TrueCap include temperature compensation, automatic immunity to material build-up on the probe by its driven shield design and external viewable LED status indicator on ordinary location models. The TrueCap product line offers a selection of options to meet the needs for a wide variety of applications.

Click here for more details on Monitor's TrueCap® level sensors or e-mail:  


Word of the Month

Plaudit (PLAW-dit)    

noun -
1) an act or round of applause
2) enthusiastic approval - usually used in plural 
1)  The latest installment in the movie series earned plaudits from critics and fans alike. 
2)  The speaker received plaudits from the audience following his inspiring speech.
To translate this word into a different language using Google translate please go to


Upcoming Holiday Schedule

Labor Day

Monitor Technologies' facility in Elburn, IL will be closed Monday, September 2nd for Labor Day.

We hope that you and your family have a happy and safe Labor Day weekend.


About Monitor

Monitor Technologies, LLC

Practical solutions at every level!


For over 50 years we have been providing high quality, reliable product experiences for the worldwide powder and bulk solids markets, backed by trusted customer service.

We believe that a practical solution is not just a plain, basic, mundane idea, but rather, a creative innovation wrapped in common sense, delivering the "exact" value that you require.
Contact us today and let us put our solutions to work for you! (level measurement blog)




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Fax: 1-630-365-5646

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