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Liquid Level Sensors

Need a liquid level sensor? Our full line of level measurement sensors is found below. Choose between 24 different products using 6 different technologies for the perfect solution to your liquid level control needs. Alternatively, you can use the menu above to narrow your search down.

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Loop Powered Ultrasonic Sensors

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Programmable Intelligence

The LPU-2428 was made with intelligent software for measurement without the need for a controller. The sensor can calculate distance, level, flow, and volume. In addition, the sensor features a 32-point linearization table for non-linear tanks and channels.

Class 1, Div. 1

This loop powered sensor is suitable for use in hazardous areas rated CSA Class 1, Div. 1.

Maintenance-Free

With a tough, IP65 rated housing, its hazardous rating, and non-contact measurement, the LPU-2428 takes care of itself.

LPU-2428 Loop-Powered Ultrasonic Sensor

Open Channel Flow Monitoring with Totalization

Range: 1 to 25 ft.
Mount: 2 in. NPT
Output: 4-20mA
Certification: CSA Class 1, Div. 1
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Easy Set-Up

We designed the LPU-2127 for easy set-up. Wiring is fast, and programming is done entirely through the integrated keypad.

Tough and Safe

With CSA hazardous location certification, and a durable housing with high chemical compatibility, this ultrasonic sensor performs well under stress.

No Fuss

The LPU-2127 is loop-powered for faster, more efficient wiring, and the easy interface and keypad eliminate the need for a computer. The sensor is virtually maintenance-free!

LPU-2127 Loop-Powered Ultrasonic Sensor

Built-in Display and Keypad

Range: 1 to 25 ft.
Mount: 2 in. NPT
Output: 4-20mA
Certification: CSA Class 1, Div. 2

DC Powered Ultrasonic Sensors

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Programming Options

The IRU-2000 sensors are designed for a variety of applications, and therefore have ample programming options to accommodate many needs.

Surface Mount

These ultrasonic sensors are built for use outside of the tank environment. Instead of a threaded fitting, they simply bolt onto a flat surface. The IRU-2000 transducers are often used for presence/absence detection, object profiling, and more.

Variety of Available Outputs

Outputs determine compatibility, so it’s nice to have options. From relays and trip points to 4-20mA and RS-485, the IRU-2000 ultrasonic sensors have you covered. Pick from our standard offerings or contact us about custom outputs.

IRU-2000 Ultrasonic Sensor

Range: 1 to 25 ft.
Mount: Surface (4 Screws)
Output: 4-20mA, RS-485, 2 Trip Points, Solid State Relay
Certification: CSA General Purpose
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Hazardous Location Certified

IRU-2420 ultrasonic sensors are suitable for hazardous locations classified under CSA Class 1, Div. 2.

Flexible Programming

This series of ultrasonics was designed with flexibility in mind. It features our AutoSense software for quick and easy programming in a variety of application settings.

A Good Fit

With a 25 ft. range, a 2 in. NPT fitting, and a 4-20mA output, the IRU-2420 sensors work well for many tank level applications.

IRU-2420 Ultrasonic Level Sensor

Range: 1 to 25 ft.
Mount: 2 in. NPT
Output: 4-20mA, 2 Trip Points
Certification: CE, CSA Class 1, Div. 2

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Class 1, Div. 2

Our customers deal with hazardous materials every day, and our sensors have been keeping them safe for years. The IRU-3430 carries on this tradition with a CSA Class 1, Div. 2 certification.

Impressively Programmable

Featuring our AutoSense software, you can program the IRU-3430 to perform the way you want it to.

Long Range

The IRU-3430 series ultrasonic sensors use a larger, more powerful transducer for a 50 ft. sensing range.

IRU-3430 Ultrasonic Level Sensor

Range: 1.5 to 50 ft.
Mount: 3 in. NPT
Output: 4-20mA, 2 Trip Points
Certification: CE, CSA Class 1, Div. 2
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Short Range Specialists

Blanking distance is a big deal with non-contact level measurement. The IRU-5000 ultrasonic sensors have brought it down to only 4 inches.

Versatile Mounts

This sensor series let’s you choose between three mounts: 1-inch threads, 2-inch threads, or 2-inch Sanitary Flange. Makes sense, right?

Output Options

The IRU-5000 series ultrasonic sensors offer 4-20mA, NPN trip points, and a programmable voltage outputs.

IRU-5000 Ultrasonic Level Sensors

Range: 4 to 79 in.
Mount: 1 or 2 in. NPT
Output: 4-20mA, 2 Trip Points, 0-2.5 V, 0-5 V
Certification: CE, CSA Class 1, Div. 2

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For Data Logging

We know that continuous level measurement, even in real-time, is always enough. So we gave you a version with the excitation feature for data logging.

Flexible Output

Sometimes it's nice to have options. The IRU-6429 offers a selectable output, either 0-2.5 V or 0-5 V. Simply program this during set-up.

Higher Accuracy

Most of our ultrasonic sensors offer accuracy of 0.25% of full scale. While this is good, this ultrasonic tightens it to 0.25% of detected range.

IRU-6429 Ultrasonic Level Sensor

Excitation for Data Logging

Range: 1 to 30 ft.
Mount: 2 in. NPT
Output: 0-2.5 V, 0-5 V
Certification: CE, CSA General Purpose
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Versatile Range

The IRU-9400 ultrasonic handles targets at distances from 6 in. to 35 ft. Measure a larger range without complex mounting arrangements.

Sensitive Transducer

This sensor uses a more sensitive transducer to detect difficult targets. It’s great for non-reflective and/or soft surfaces. At the same time, it is not sealed for harsh environments and is recommended for use indoors and away from dust.

Object Detection

With the more sensitive transducer and superior range, the IRU-9400 is well suited for object detection applications.

IRU-9400 Ultrasonic Sensor

Greater Sensitivity for Indoor Use

Range: 0.5 to 35 ft.
Mount: 2 in. NPT
Output: 4-20mA, 2 Trip Points
Certification: CE, CSA General Purpose

Remote Monitoring Ultrasonic Sensors

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Inexpensive

The LOE ultrasonic sensor line is designed for remote level measurement. This is traditionally a very expensive endeavor. We simply tie into the existing Internet backbone for inexpensive, web-based remote level measurement.

Web-Based Programming

LOE liquid level sensors are fully programmable for various applications, giving the user complete control. In addition, the LOE can be programmed remotely via the Internet, in the comfort of your office.

Intuitive Web Interface

The online monitoring portal is a powerful tool for remotely monitoring levels no matter the distance. The site offers data logging, email and text (sms) alarms, history graphs, and more, all in an intuitive, easy-to-use package.

LOE Remote Monitoring Ultrasonic Sensor

Remote Access to Level Data

Range: 4 in. to 40 ft.
Mount: 2 or 3 in. NPT
Connectivity: LAN or Internet
Certification: CSA Class 1, Div. 2

Ultrasonic Sensor/Controller Systems

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Inexpensive Control

The DST ultrasonic level sensors work in conjunction with the DCR controllers to give you a simplified, stand-alone system for level measurement and control.

Field-Proven Solution

This system of DST liquid level sensors and DCR controllers has proven itself for over a decade, and still solves applications today.

Flexible

Because there are several sensors and controllers to choose from, using DST ultrasonic sensors give you plenty of options for your application needs.

DST Ultrasonic Level Sensors

For Use with DCR Controllers

Range: 4 in. to 50 ft.
Mount: 2 or 3 in. NPT
Output: 0-2.5 V, 0-5 V
Certification: CSA General Purpose
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Simple, Low-Cost Control

The DCR controllers and DST ultrasonic sensors work together to allow simple level monitoring and control without the need of a more advanced system.

Tried and True

This system has reliably performed for fifteen years, and still meets application needs today.

Versatile

This series of ultrasonic sensors and controllers offers a wide variety of options for mounts, range, and outputs.

DCR Controllers

For Use with DST Ultrasonic Sensors

Input: DST Senors, 4-20mA, 4 Dry Contacts
Output: 4 NO Relays, 4-20mA, 0-5 V, 0-10 V
Protection: NEMA 4X, IP65, NEMA 1, IP10

Magnetostrictive Level Probes

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Made to Order

MPE level probes are highly customizable, including such options as housing material, stem length, mounting options, and float type and specific gravity.

Modbus RTU

Outputs and connectivity can make or break the success of any measurement endeavor. The MPE level float sensor uses Modbus RTU for high compatibility with your control network.

Fine-Tuned Accuracy

The MPE level probe features one of our highest resolutions at just 2 mm, with an accuracy of ±4 mm. In short, you can really dial-in on the liquid level in your tank.

MPE Magnetostrictive Liquid Level Probe

High Resolution Level Probe

Max Length: 153 in.
Mount: NPT, Flange, No Mount
Output: 4-20mA Loop-Powered, Modbus RTU (RS-485)

Resistive Chain Level Probes

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Custom Made

The RP level probe is fully customizable. From stem, or probe, length to float size and specific gravity, the RP level float will be tailored to your exact application needs.

Tough

This level float is installed in some of the toughest applications in the world. The RP probe features superior quality, and high chemical compatibility to endure almost any level measurement application.

Linear Simplicity

The RP probe makes level control easy. With simple “float-goes-up, float-goes-down” operation, this liquid level probe is far less prone to interruptions in performance or accuracy.

RP Liquid Level Probe

Level Probe for Small Tanks

Max Length: 96 in.
Mount: 2 in. NPT
Output: 4-20mA, Resistive
Certification: CSA Class 1, Div. 1
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Heavy Duty Explosion Proof

This level probe is built for heavy-duty applications that require ATEX or CSA intrinsic safety, or CSA explosion proof certifications. It’s large float works well in dirty environments, and has been proven for years in the oil & gas and wastewater industries.

Made to Order

Probe length, float type, specific gravity, even outputs can all be customized to your needs. The RPM liquid level probe is meant to work for you.

No Fuss Operation

The RPM level float doesn’t struggle with many of the same variables that plague non-contact forms of measurement. With simple linear measurement, there is little that can disrupt the operation or the accuracy of the RPM.

RPM Liquid Level Probe

Large Hazardous Location Level Probe

Max Length: Custom
Mount: NPT, No Mount, Flange
Output: 4-20mA Loop-Powered, Resistive
Certification: CSA Explosion Proof Class 1, Div. 1

Cable Suspended Float Switches

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Built Better

The KA float switch features a high chemical compatibility, a stronger cable, and durable components that simply last longer than the competition.

Level Control

This 4-point level switch is meant to replace four single-level float switches. It can accomplish the same functionality with only one float, saving you money and getting the job done.

Non-Toxic

Rest assured, these float switches use no lead and no mercury.

KA 4-Level Float Switch

No Lead, No Mercury, Hysteresis and Duplex Control

Material: Polypropylene
Cable Length: 5 m, 15 m, Custom
Switch Points: 4 NO, NC, 7 Configurations
Certification: CE, CSA General Purpose
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Rugged Design

Our KA float switch is built to last years in tough environments. The float is designed with excellent chemical compatibility, constructed with high grade materials, and is durable enough to take a beating.

Get What You Need

With four configurations, the KA 3-level float switch can do fill control and empty control with alarms, with isolated alarms, and with hysteresis.

Environmentally Safe

Float switches of this nature once used lead and mercury in some of the components. This practice has been changed, and our sensors do not use lead nor mercury.

KA 3-Level Float Switch

No Lead, No Mercury, Hysteresis with Alarms

Material: Polypropylene
Cable Length: 5 m, 15 m, Custom
Switch Points: 3 NO, NC, 4 Configurations
Certification: CE, CSA General Purpose

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Superior Quality

Competitors simply cannot match the durability. The KA float switch is built with the highest quality materials and features a high chemical compatibility.

A Variety of Options

With dual switch points, the KA 2-level switch can give high and low alarms, or do fill and empty control.

No Lead, No Mercury

The KA float switch has neither lead nor mercury for safe, worry-free operation.

KA 2-Level Float Switch

No Lead, No Mercury, Hysteresis Options

Material: Polypropylene
Cable Length: 5 m, 15 m, Custom
Switch Points: 2 NO, NC, 3 Configurations
Certification: CE, CSA General Purpose
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Quality Built to Last

From a stronger cable, to a high chemical compatibility, to durable components, the KA level switch is built to outlast any other.

Multiple Configurations

In addition to normally closed, or normally open, the KA single point float switch can be configured with both high and low alarms, as well as dual low or dual high alarms.

Mercury and Lead Free

Unlike some of our competitors, these cable-suspended float switches are mercury and lead free.

KA 1-Level Float Switch

No Lead, No Mercury

Material: Polypropylene
Cable Length: 5 m, 15 m, Custom
Switch Points: 1 NO, NC, 5 Configurations
Certification: CE, CSA General Purpose

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Inexpensive Float Switch

The FT-100 water level switch gives value with high quality at a low cost. If budget is your primary concern, the FT-100 can give you effective single point alarming and control with a small price tag.

Consistent Performance

This water level sensor is built with consistency in mind. It triggers immediately above or below horizontal, for a highly repeatable performance that you can count on.

Suitable for Potable Water

Not every float switch on the market can be used in potable water. The FT-100 water level sensor passed the NSF Standard 61 protocol by an approved Water Quality Association laboratory.

FT-100 Water Level Sensor

Float Switch for Wastewater or Potable Water

Material: Polypropylene
Cable Length: 20 ft., 30 ft.
Switch Points: 1 NO, NC, SPDT
Certification: CE, CSA General Purpose, UL, NSF Standard 61

Stem Float Switches

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Customizable

The FL multi-level float switch comes made to order. From switch configurations to float types and materials, the FL level switch adjusts to meet your specifications.

Works in Tight Spaces

Unlike suspended float switches that require room to operate, this vertical float switch works along a probe, or stem, for linear level measurement in a tight space.

Up To Seven Switch Points

The FL float switch offers up to 7 switch points for increased control and savings. Monitor 7 different levels with a single sensor, and a single mount.

FL Multi-Point Float Switch

Customized Point Level Control

Material: 316L SS, PVC, More Options Available
Max Length: 153 in.
Switch Points: Up to 7 NO, NC, Custom Configuration
Certification: CSA General Purpose
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Class 1, Div. 1

The FLX float level sensor is the float switch for use in hazardous locations considered Class 1, Div. 1 areas by CSA for North America.

Configuration Options

Pick the most effective switch point configuration for your needs. Choose between either Normally Closed or Normally Open for each switch point on the stem.

More Level Control

With up to 7 switch points, the FLX float switch gives you more control. Place them wherever needed along the stem for a customized fit to your application.

FLX Hazardous Location Float Switch

Level Switch for Hazardous Locations

Material: 316L SS, PVC, More Options Available
Max Length: 153 in.
Switch Points: Up to 7 NO, NC, Custom Configurations
Certification: CSA Class 1, Div. 1

Miniature Float Switches

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Compact

These small float switches offer multiple form factors and functionalities to fit wherever needed inside a system. Their compact size is perfect for a variety of OEM applications.

Low Cost

Due to the simple nature of their operation, the LF miniature float switch series features a low cost for reliable performance, especially in large volumes.

Long Life

The LF miniature float switch series is designed for shock resistance, chemical compatibility, and a life long reliable performance.

LF Miniature Float Switches

Compact for OEM Applications

Material: Polypropylene, Buna, PVDF, 316L SS, 304 SS, 6-Nylon
Style: Various, See datasheet
Switch Points: 1 NO, NC

Movable Stem Float Switches

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Direct Pump Control

The MLS float switch has a 10 A SPDT miniature switch for direct control over small horsepower pumps.

Field Adjustable

The two float stops on the stem of the MLS float switch are field adjustable for optimum switch point control. Simply loosen the screw on the float stop, slide it up or down, and tighten it again.

Mechanical Hysteresis

The MLS float level sensor switches on when the float hits the top float stop, but does not switch off again until the weight of the float itself lands on the bottom stop. This mechanical hysteresis is ideal for pump control.

MLS Mechanical Float Switch

Movable Stem, Single Point Level Control

Material: 304 SS, Polycarbonate & Neoprene
Max Length: 59 in.
Switch Points: 1 SPDT NO, NC
Certification: CSA General Purpose

Submersible Pressure Transducers

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Field Calibration

The PT-500 submersible pressure transducer can be calibrated easily in the field to keep it performing in tiptop shape.

Lightning Protection

The PT-500 undergoes rigorous testing, and is protected against lightning strikes according to the IEC-61000-4-5.

Patented Removable Cage

The PT-500 pressure transducer is built for some of the most hostile level measurement conditions. However, when replacement day eventually comes, we’re the only ones who let you keep the cage so you can save money on the next sensor.

PT-500 Submersible Pressure Transducers

Hydrostatic Pressure Sensor

Output: 4-20mA
Range: Up to 450 ft.
Lightening Protection: IEC 61000-4-5
Certification: CSA Class 1, Div. 1

Remote Communications Modules

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Inexpensive Communications

Unlike competing methods for remote monitoring, the RST-5001 simply connects to a pre-existing Internet connection or LAN. Data can be viewed by an online data portal, or on a LAN connection.

Extremely Easy Set-Up

Simply connect the RST-5001 remote communications module to any 4-20mA sensor via the input terminal and plug in an Ethernet cable. The module will send sensor data through the cable to a local area network or the Internet.

Local and Remote Alarming

In addition to two isolated solid-state relay trip points, the website that the module connects to can send both text (sms) and email messages when pre-defined values are reached.

RST-5001 Internet Communications Module

Remote Communications for any 4-20mA Device

Input: 4-20mA
Connectivity: LAN or Internet
Mount: Din Rail

Other Liquid Level Switches

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Long Life

With few moving parts, only a flexing diaphragm, the NLS pneumatic point level sensor lasts long and is very reliable.

Low Power Operation

The NLS requires no power to operate it sensing elements, and provides a dry contact output.

Field Adjustable

Install a ½ in. pipe of your choosing in the bottom of the sensor housing, protruding past the switch point in the tank. The switch point is easily adjusted by your choice in pipe length.

NLS Pneumatic Level Sensor

Mount: G 1 Male
Output: 1 SPDT NO, NC
Range: 8 to 200 in.