Fluid Switch Blog

Category Archives: Ultrasonic Liquid Level Sensors

A Sweeter Maple Syrup Season with Level Sensors

maple syrup

In just a few short months, farmers here in New England will gear up for one of the most important seasons of the year – Maple Syrup making! Perhaps one of the most favored products to come out of the region, maple syrup is treasured by many as a sweet and delicious topping for everything from pancakes to ice cream and a number of other dishes.

In 2017, a reported 4.3 million gallons of maple syrup was produced I the United States with Vermont and New Hampshire both contributing a large part to that count. This year is expected to be great for sugaring as well.

If you’re looking for a solution to assist with your maple syrup production, let SMD Fluid Controls help!

Keep reading to learn how.

The steps involved to collect and then process syrup require special skills, tools and know how. Constant changes and improvements to the processes involved have occurred over the years to ease the time required to create maple syrup. Still, the key focus remains to produce a maple syrup with a sweet and distinct flavor. To do so, temperature and storage play a critical role.


First things first, to convert the maple sap coming out of a tree into syrup, it needs to be collected from the tree. Buckets with a tap that’s driven into the tree and a spout are hung on the trunks as sap slowly spills in. Once a sufficient amount is collected, it’s then taken for a water removal process known as “evaporation.”


tree sap bucket

In the production process, it’s easy for the foam to be formed or sugars to burn if sap levels are too low and these occurrences could ruin a lot of syrup in a short period of time. For this reason, carefully monitoring liquid levels is critical to keep batches in top condition.

In this example, an ultrasonic liquid level sensor could work inside of a collection vessel to not only help monitor the levels at which the buckets are filling up but do so without needing to touch the contents inside for hygienic reasons.

Just imagine the time saved versus having to walk the property tree by tree to check on the status of that sap collection?


To create syrup out of sap, water must be removed from it. This is done by boiling it to a specific temperature for a designated period of time and is key in producing a high-quality syrup product.

Even the bottling of the syrup should be done at a certain temperature.

Take the guesswork out of the equation here with float switches and level sensors incorporating RTD’s, thermocouples, or thermostatic devices that work to maintain appropriate temperatures and ensure storage and capping of liquids is happening properly.

A float switch could also be used to monitor liquid levels and activate a pump or sound an alarm if necessary to prevent overflow or production damages.

 At SMD Fluid Switch, we help lower costs and increase productivity. From competitive pricing for OEM designs and applications as well as custom designs to meet a variety of needs.

Contact us today to get started!

How to Choose a Level Sensor

level sensor

We speak frequently about the various applications where level sensing is used and how to best provide accurate measurements. But for this post though, we’ll be going back to basics to overview some of the most important things to consider when you are choosing a level sensor. After all, this decision will be the measure that keeps your machines and operations running smoothly and safely.

Step 1: Determine the Substance & What Must Be Measured

This is perhaps one of the most important factors in choosing a level sensor. Different liquids characteristics must be considered to make an accurate measurement. For example, highly viscous liquids like oils and grease can change the sensor requirements.

Other factors that affect monitoring a liquid level is factoring in if there could be build up in the tanks if it will be sticky or corrosive, and even the specific gravity of the liquid (the ratio of the object’s density to that of water).

In addition to the liquid being measured, you must also consider the tank that’s holding the material as its part of the larger picture.

For example, if there are limits to how the sensor is mounted to it, if the temperature inside must remain a certain degree or if there are pressure requirement or vibrating conditions that could possibly alter the accurate measurement, you’ll need to consider these factors in advance.

Determine if switching or continuous level monitoring is required for the application prior to making a selection. Also, submersible sensors placed inside a tank or those that are mounting externally are options you’ll need to choose from.

Step 2: Consider Conditional Factors

Outside of the most basic elements detailed above, you’ll need to also consider conditional factors that could change your options for level monitoring.

Can the contents inside the tank make contact with the sensor at all? Will it affect performance over time if so? Level sensor options will change based on these details.

  • Pressure sensors provide accurate measure using the measure of the bottom and open space within a tank.
  • Float switches work by measuring the level of a liquid based on its ability to float on the surface. They can be mounted vertically or horizontally and mounted on the inside or outside of a tank.
  • Ultrasonic level sensors use waves and echoes to measure a substances level and service.

Gathering as much information as possible will arm you with key information to make the best decision for level sensors.

Have questions? Need Answers? Speak to the professionals at SMD Fluid Controls. We can make recommendations, build custom solutions that work for you and help you feel confident you’re making the right choice for your application.


Level Sensors: How They Work & What They Do

liquid level sensors

How do you measure the level of liquid in a contained space that’s flowing freely and in some cases too hot or dangerous to come in contact with? The answer is –  Level Sensors.

Using a magnet and reed, the most basic sensors can monitor liquid levels through the activation of switches that activate alarm about too much or too little liquid present in the container.

But don’t let their simplicity fool you. Level sensors aren’t just loved because of their cost sensibility, they are also vital to operations in industries across the globe. They don’t just measure the presence of a medium in a container, but also the absence. These low-level warnings and can even detect leaks before dangerous situations occur. This accuracy and dependability keeps businesses successful and the public safe.

Liquid measurement and monitoring is so important in fact, that new devices and technologies continue to incorporate the sensors in them as a way to deliver important data to and from advanced machines.

Depending on the type of process materials being measured, different sensor types can be used.

Two options for how to handle materials are typically chosen from – contact or non-contact measurement. This is based on various factors from the density to the temperature of the material being measured and whether or not there are sanitary requirements. As the name indicates, a contact measurement method would be the sensor located inside the vessel itself and able to come in contact with the material being measured without putting the project at risk. A non-contact method would include a sensor mounted to the outside of the tank.

Here is a break down on the different types of sensors offered by SMD Fluid Controls.

Contact Sensors:

Float Switches – These are the most commonly used devices for level measurement and utilize magnetic floats and reed relays to measure liquid medium.


FL50 – Chemical Resistant Plastic Ultrasonic Point Level Sensor


Contacting UltrasonicThese options are great for point level measurement of liquid and work by measuring the timing and speed of sound waves.

Optical SwitchesThese sensors have built-in electronics and work with no moving parts. They can perform point level sensing and pressure sensing up to 2500 psi.

optical sensor

OS950 – Miniature Plastic Optical Level Sensor

Submersible Tank Level Sensor – These are a versatile option that can gauge tank levels by the hydrostatic pressure and offer stable and continuous measurement from depths up to 211 meters.

submersible sensor

FT60 – Downhole Submersible Level Sensors

Non-Contact Sensors:

Ultrasonic Radar – This option uses radio waves to measure levels and is best for highly viscous or difficult liquid media that must be measured in real-time. Our ultrasonic sensors are made from 316 stainless steel and have a temperature maximum of 90°C with pressures up to 5,000 PSI in custom configurations.

Load CellsThis non-contact method of measurement is typically used outside of a tank to measure its contents by weight and may be suitable when non-contact with materials being measured is required.

Ready to order? Have questions?

Whether you need a prefabricated float switch or a custom designed liquid level sensor, we can help! Our full OEM services are available whatever your industry and whatever your needs! Contact us today!

Better Irrigation Management with Ultrasonic Liquid Level Sensing

irrigation on farm

It’s no secret that today’s farmers and the agricultural industry as a whole are faced with many challenges when it comes to providing high quality and consistent food for consumption.

One of the largest risks is food waste and the discarding of less than perfect crop yields for selling in stores. These deformed fruits and vegetables and those with abrasions are adding up 20 billion pounds of produce that are being left out.

The USDA has found that “30 million acres of cropland, 4.2 trillion gallons of irrigation water, 1.8 billion pounds of nitrogen fertilizer, and 780 million pounds of pesticides went into producing food that was thrown away.”

Controlling the delivery of water to crops is important for sustaining profitable yields of food production and has been around for ages.

For this blog, we’ll look at a key way to turn things around and it starts crop-level with the resources being used to monitor and deliver vital water to these plants. Referred to as, “precision agriculture” farms can maintain precise water allocation as a tool for curbing food waste.

This is done through the use of ultrasonic liquid level sensors.

Today, automated irrigation distribution systems are becoming a popular choice over traditional methods because they remove the intensive human labor required to open and close gates and they provide much greater accuracy when it comes to water level measurement.

As an effective method, irrigation staff is no longer needed to manually raise gates to release water. Not only reducing intensive labor demands and saving water but also removing the factor of human error from the equation.

Utilizing ultrasonic liquid level sensing, sensor-driven channel gates that distribute precise volumes of water based on requested parameters are possible.

There’s more.

The sensors are also collecting important data that can be shared with farmers to provide exact details on how much water was delivered and help define future orders. Reducing waste of precious water resources especially during a drought, and even protecting crops from rot and damage due to overwater.

SMD Fluid Controls offers a variety of ultrasonic liquid level sensors and transmitters for continuous, non-contact tank level measurement. Our industrial ultrasonic sensors operate using the most state of the art working principles and are available in a variety of materials and prices.

Get in touch to learn more about how we can help with your application’s specific requirements.

Don’t Risk Boat and Off Road Vehicle Shutoff, Use Liquid Level Sensors

Loading a Boat

As warm weather makes its way to more parts of the country, there will be an increase in the use of boats and off road vehicles. Whether you seek outdoor adventures for a weekend pastime or depend on boating and off-road vehicles to perform job related tasks, keeping these vehicles up and running is important.

In this post we’ll discuss one possible issue with low oil levels and how a liquid level switch can be the perfect solution.

The Problem:

Getting an accurate oil level read in your boat or ATV’s tank could lead to engine failure, shut-off, being stranded and other breakage. The old fashioned dip stick is good for a quick rough estimate, but it’s not accurate to give you a fair warning that fluids are running out.

The Solution:

If the OEM had integrated a liquid level oil sensor into their design, it would be possible to get a more accurate measurement and a much more advanced notice of a potential engine failure due to low lubricant.

How Liquid Level Sensors Work

Liquid level sensors are the most accurate and reliable way to measure oil tank levels. These sensors can automatically sense the levels of the liquid in the tank and then electronically communicate that reading to you.

These readings offer precise levels to warn about low level, high level and overflow of oil in the tank to ensure safe and efficient operations while keeping the motor moving and keeping you working efficiently.

Liquid level sensors for tank level monitoring, fuel and chemical injection and other applications have all been crucial to the continued advancement of the oil and gas industry in every step of the processes they require.

FL50 Chemical Resistant Plastic Ultrasonic Point Level Sensor

The FL50 Chemical Resistant Plastic Ultrasonic Point Level Sensor from SMD Fluid Controls is a terrific option. Made with durable nylon or polypropylene it offers unmatched chemical resistance across a wide range of industrial applications, including with hydraulic fluids, oils, and slurries.

Through high frequency sound waves, the ultrasonic level sensors can detect changes in the waves as they bounce back to the sensor, making them capable of both point level and continuous sensing applications.

Like all of our level sensors, the FL50 can be custom-engineered to manufactured to meet your specific requirements.

Not sure which level sensor you need? Let us help!

Since each application varies, it’s important to use the right level sensor for specific needs. If you need assistance choosing the right level sensor, SMD Fluid Controls can help. Our corrosion-resistant level switches, non-contact ultrasonic models, and more offers what you need to get accurate reads and critical advanced notice.

Level Sensors Make Portable Power Reliable


Schools will be out for summer break soon and temps are warming up for most of the nation. While it may mean poolside relaxing and vacations for some, for many who work in the construction and maintenance industry, busy season is just getting started.

To help keep these sites up and running, many rely on portable power units that deliver necessary electricity and cooling.

Generators and portable air units make it possible to continue working for the duration of the project and are an important, hardworking element of the job. These offerings can be purchased or rented for use during temporary, emergency and permanent applications. Regardless of what they will be used for, their reliability is of extreme importance.

How can they ensure continued performance?  With level sensors.

How Level Sensors are used in Portable Power Equipment

For temporary power needs, generators are a top choice at commercial sites. To keep them running, fuel must be present in the system. With a level sensor it’s possible to monitor fuel levels so there is no risk of power loss or shut off. In emergency situations and where power loss would be detrimental to operations, this monitoring is especially critical.

Loss of fuel for portable equipment also translates to money lost for businesses. Employee downtime, temperature issues and even recharge costs can also all create problems.

Instead, a reliable level sensor can measure the presence of fluid (in this case fuel) inside of the tank to assist in keeping the power equipment functional.

Depending on an applications needs, single point, multi-point or continuous monitoring level sensors can be used.

For oil & gas, an ultrasonic liquid level sensor is typically be used. These sensors emit pulses of sound at the liquid surface and record and calculate the time it took for the sound wave to bounce back. The lower the liquid level, the farther the sound travels and the longer the process takes.

If you’re looking to keep your portable power solutions working at optimal efficiency and make them dependable, contact SMD Fluid Controls today.

Agricultural Drones: Helping Modern Farmers to Be Fruitful

agriculture drones

An unmanned aerial vehicle (UAV) is not a new technology. While early use came from assisting with military operations, these lightweight, remote controlled devices are now being used for a number of capabilities – from basic hobby-grade to very technologically advanced uses in industrial and commercial settings.

A study from PwC, “Clarity from Above” found the global market for drone powered business solutions to be valued at $127.3bn with agriculture being one of the top 3 industries primed for drone use.

In agriculture, one of the latest industries to increase tech investment, drones are making it possible for farmers to improve crop production and reduce waste. Drones are being used to not only improve the future of food production but also play an important role in speeding up critical decision-making in the agricultural field.

How Drones Are Used for Today’s Farms

As the world’s population grows and resources shrink, it’s become more important than ever for farmers to work smarter. Drones allow them to gain a better overall view of their fields and crops and increase efficiency.

Drones can be used to:

  • Carry and release liquids
  • Scan for disease and other issues
  • Address extreme weather conditions & better manage crop growth
  • Planting systems and soil analysis

Optical Sensors, Float Switches & Drones

Cameras are the most common technology included onboard drones but there are other technologies that can be added to further increase effectiveness of the job these devices do on the farm.

More sophisticated sensors and deeper automation capabilities can create additional opportunities for success. Optical and ultrasonic sensors for example, are small and lightweight and have accurate dependable measurement abilities so farmers get a broader and more accurate view of their fields.

When it comes to irrigation needs, the inclusion of thermal sensors that can measure temperatures and detect the presence or absence of liquid (i.e. drought) are important. These systems could also be connected to a system to sound an alarm or even activate a switch to allow proper watering to begin in hopes to keep the crops alive.

Ultrasonic sensors that listen for echoes to sense the amount of liquid present are also key to ensuring the proper amount of pesticides, herbicides or even water are sprayed to cover needed areas. This gets the job done quicker and with better precision than ever before possible.

One of the biggest issues plaguing farmers is the spread of disease that can threaten their entire yield. With optical sensors on a drone, it’s possible to spot possible issues early and make quick decisions to save the rest of the field before it becomes a larger issue.

Have questions? Speak with one our experts to discuss any problems you are facing and to find a solution that fits your needs.

At SMD we can make sensors to measure anything and offer competitive pricing for OEM designs and applications. These include machined level sensors, optical switches, ultrasonic level measurement, and custom molded float switches in metals or plastics like stainless steel, polypropylene, and nitrile butadiene rubber (NBR).

Contact SMD Fluid Controls today!

Low vs. High: How Fluid Viscosity Effects Float Switches and Level Sensors

thick, viscous, honey

Measuring fluids, and doing so with precision is exactly what float switches and level sensors were created to do. Regardless of application, their ability to measure and identify the presence or absence of a liquid in a vessel is critical.

There are however, some factors to take into account when selecting the proper level sensor or float switch – one of the most important being the type of liquid being measured.

Is it corrosive? Thick? Hot? These elements can all affect how measurements are taken.

For this post, we’ll be focusing on viscosity and how highly viscous (thick) liquids (think oil, paint, molasses) present a unique challenge for measuring.

Why High Viscosity is an Issue

Viscosity is used to describe how thick a substance is and defines its ability to change shape under stress or tension. To give you a better idea of the differing viscosity levels or centipoise (cP) measures, water measures at 0.894 cP, castor oil at 650 cP and ketchup at 50,000 – 100,000 cP.

As you can see the “thickness” plays a major role in how freely these different fluids can flow.

When trying to get an accurate measure you cannot use the same float switches or liquid levels in every situation. Problems including the float getting stuck or even damaging the pressure ports are all possible.

Keep in mind too that temperature conditions can change viscosity levels so be sure you’re selecting a solution that is most compatible with your specific application.

The Solution

The best option for high viscosity liquids is to opt for non-contact options like optical or ultrasonic level sensors for accurately measuring liquid levels.

Here’s why:

Acoustic waves emitted by ultrasonic liquid level sensors and the measuring of the echo returned, make it possible to know liquid levels without ever having to physically touch the matter – eliminating the risks mentioned earlier.

With optical switches, measurement is done using a laser wave or forward light scattering and a probe. There are no moving parts and the option works well because it can measure the presence or absence of many different types of liquid.

Need help choosing the right solution for your application? Let SMD Fluid Controls help.We work to lower costs and increase productivity for all of our clients, offering competitive pricing for OEM designs and applications.  Contact us today to get started.

Clean in Place & Pharmaceutical Manufacturing

Hygienic, sanitary measures are critical in many manufacturing facilities. From food and beverage to semiconductor and pharmaceutical, these systems ensure cleanability while reducing product loss and downtime.

Known as Clean in Place (CIP) these systems use water, heat and/or chemicals to clean and sanitize machines and other areas of a plant removing dirt, spores and other bacteria, both visible and not visible, to guarantee cleanliness.

Contamination Prevention Market

Demands for equipment that cleans is rising in the pharmaceutical industry with purchases reaching close to $550M in 2019 according to the latest report from the McIlvaine Company titled, “Ultrapure Water: World Markets.”

Ensuring these machines function optimally requires the proper fitting and connections as well as automated technologies like sensors to indicate what’s happening on the inside of a vessel.

Improper chemical use and fitting options can cause erosion, breakage and present a host of other dangers.

Tri-Clamp and Fittings

Not only is keeping clean a priority, but these systems also need to prevent product mixing, contamination and allergens or microbial threats. Fittings that are tight and durable and that are made of cleanable finishes are all critical.

A Tri-Clamp is the best option for a fitting/connection in these settings because it is sanitary, easy to clean and does not leave room for leaks. A tri-clamp also meet today’s strict sanitary and quality standards and can withstand high temperatures present in most sanitation systems for pharmaceuticals.


How Level Sensors Help

Optical sensors and other instruments are being used in these applications to help improve cleanliness and control contamination. Through the use of level sensors connected to pumps and valves, it’s become more cost effective for pharmaceutical plants to sanitize tanks, purify water, and more. Sensors that can measure the product and the detergent in a tank can also provide information on tank levels, and flow measurements.

Fluidswitch’s FM series Stainless Steel switches are perfect in these environments because they are corrosive resistant, used to control pumps and alarms and can indicate general fluid levels.

Have questions? Let us help!

Customizing A Multi-point Level Sensor for Chemical Tanks: 3 Things to Consider


Level sensors are used to measure the presence or absence of a substance in a vessel, tank or other system. The sensors can measure either the exact amount (continuous level sensors) of liquid or can be used as a way of determining if the level of a liquid is high or low (point level sensors). There are also ultrasonic level sensors that work by emitting acoustic waves which are reflected back to a transducer to measures the response and determine liquid levels.

In some tanks, there is more than one liquid present needing measurement. Multi-point level sensors are used in these situations and can monitor multiple liquid level points within a single tank. These sensors regulate liquid levels, detect fluid leaks, and so much more.

Their importance is further amplified when chemical contents are present which can pose unique dangers. In these challenging environments, customized solutions can be created to meet specific application needs and ensure accuracy and reliability.

SMD Fluid Controls engineers can design custom multilevel sensors to meet your specific needs.

Here are the top 3 things you’ll need to consider when customizing a multi-point level sensor for a chemical tank.

1.      Proper Fit

Finding the proper fit for each application is key. The fit, size, type and even how the sensor is mounted to the tank will vary depending on different factors. With ultrasonic sensors for example, the right mounting will provide accurate responses when measuring sound waves. In smaller tanks with restrictive spaces, sensors may be mounted externally or using a different custom fit.

multilevel sensor

2.      Contact or Non-contact

It’s also important to factor in whether or not there will be chemical or liquid contact with the float switch. In cases where corrosion is possible, a stainless steel custom multilevel float switch that can resist damage as well as high temperatures and pressure is the best option.

3.      Device Requirements

Be sure to look at the big picture when selecting a float switch. Factor in what it will control, power and electrical requirements should all be determining factors in your selection.

The FM04 (pictured at the top of this post) is just one example of a plastic custom multilevel float switch whose materials are compatible with a wide range of chemicals and can be customized for a range of sizes to work in an endless variety of applications.


Contact the knowledgeable team at SMD Fluid Controls to learn more today.