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LowProfile Load Cells 101

In the field of force measurement, load cells are defined by a set of specifications attributed to a configured shape and size of the flexure model. These models are engineered to meet requirements in weight, size, cost, accuracy, use life, rated capacity, extraneous forces, test profile, error specs, temperature, altitude, pressure, and materials.

Of all the flexure models available, the low profile load cell is the most common force measurement sensor model used for general test and measurement applications.

Did you know that Interface is known for creating the first low profile load cells more than 50 years ago? Our founder first introduced the low profile in 1969 and later trademarked as the first of its kind precision LowProfile® Load Cell by Interface. With this invention, Interface became with market leader of precision load cells. In fact, our 1200 Standard Precision LowProfile® Load Cell, designed for eccentric load compensated tension and compression, remains our most popular product today.

This pancake-style shear beam cell design is world-renowned for durability, accuracy, and performance. The LowProfile design resembles two shear beam cells end-to-end, exhibiting the stability of a doubled-ended shear beam and augmented by the fact that the circular design is equivalent to four double-ended cells. Thus, it provides stability in eight directions at the center point.

The LowProfile designs include a base, bolted to the flexure around its outside rim. The base is a flat surface, guaranteed to provide optimum support for the flexure. The use of a base ensures the exceptional performance in the Interface LowProfile series, as each load cell is built, evaluated, and calibrated with the base.

Advantages of all Interface LowProfile design include:

  • Higher output
  • Better fatigue life
  • Better resistance to extraneous loads
  • Shorter load path
  • Extremely low compliance with higher stiffness
  • Option for compression overload protection integral to the cell
  • Proprietary strain gages
  • Customization

One process step that is standard in the LowProfile series is the adjustment to extraneous load sensitivity. Although the design itself cancels out the built of this sensitivity, Interface goes one step further and adjusts each cell to minimize it even more.

The Interface LowProfile Series is available in compression-only, tension and compression and calibration grade. There are high and low-capacity options, flange-style, amplified, as well as fatigue rated models. Various features are available through hundreds of configurations to accommodate the wide range of testing profiles, such as connectors, wireless, additional bridges, and overload protection.

The LowProfile Series has three major classifications: precision, ultra precision and fatigue rated. The basic construction of all the cells in the series is quite similar. The major differences are in the number of shear beams and the number of gages in the legs of the bridge.

LowProfile Precision Series: Standard capacities of the precision low profile designs can measure up to 2M lbf. The gaged sensors in every load cell are individually inspected and tested and certified to meet our rigid standards. With greater stiffness, respectable static error band specifications and resistance to extraneous loads, this is Interfaces number one line of products.  The standard 1200 is by far the most sought after low profile today.

1200 Precision LowProfile Load Cell Standard Series features:

  • Proprietary Interface temperature compensated strain gages
    Performance to .04%
    High output – to 4 mV/V
    0.0008%/°F (.0015%/°C) temperature effect on output
    Low deflection
    Shunt calibration
    Barometric compensation

This 1200 Standard Precision LowProfile® Load Cell standard model is available through our QuickShip48 expedited delivery service. Click here to order now. For additional low profile capacities of the Model 1200 series, base options, connectors, bridge options and overload protection availability, go here for the specifications datasheet, model options, drawings and technical specifications.

LowProfile Ultra Precision Series: Engineers at Interface designed this series to meet the demands of sophisticated testing labs with precision performance in the critical parameters such as static error band, non-linearity, hysteresis, non-repeatability, and extraneous load sensitivity. The models in the 1100 Ultra Precision LowProfile® Load Cell are the most popular of this design.

LowProfile Fatigue Rated Series: This series guarantees fatigue life of 100 million fully reversed load cycles.  This series has tighter specifications on resistance to extraneous loads and offers stiffer compliance. Interface’s fatigue rated load cells typically have static overload rating of 300% in both tension and compression modes. Originally designed for aerospace testing, the Interface 1000 Fatigue-Rated LowProfile® Load Cell are the most used fatigue-rated low profiles.

Interface also provides very high-grade low profiles for calibration. The LowProfile Gold Standard Calibration Series: Interface sets the standard in precision load cells. The model 1600 Gold Standard® Calibration LowProfile® Load Cell are uniquely designed for calibrating other load cells to the highest levels of quality and accuracy used in test and measurement. The Interface Model 1600 provides both tension and compression in one unit. It also has the options for a second and third bridge, as well as overload protection.

1600 Gold Standard® LowProfile® Tension and Compression Load Cell Standard Series features:
• 0.01% creep
• High Output to 4 mV/V
• High-Precision Installed Base
• ±0.0008%/˚F Max Temperature Effect on Output
• Low Deflection
• Shunt Calibration
• Barometric Compensation
• Calibration Adapter
• 3-Run NIST Traceable ASTM E74 Calibrations
• 4% Lower Load Limit per ASTM E74

Low profile load cells are used for all types of testing. There are many options and designs available as standard models. We also provide engineered to order, custom and OEM solutions for all our load cells. As with all our standard load cells, we do offer various capacities, modifications, and custom options.

One thing that is for certain, the Interface LowProfile is a standard across the force measurement industry. They are common in testing rigs, designed in as components, often found in the best metrology labs throughout the world.  Industry leaders in manufacturing, aerospace, automation, food processing, medical and biosciences, energy and transportation choose LowProfiles for the meticulousness required in high-performance force measurement testing.

Low-Profile-Load-Cell-Brochure

Interface 1200 Precision LowProfile Load Cell Series Product Highlight

As a premier force measurement solutions manufacturer of more than 53 years, Interface has developed a giant catalog of more than 30,000 products that are standard, engineered-to-order and completely custom. We’ve seen nearly every challenge and complexity presented by our customer’s application requirements.

Load cells are what we know, inside and out. By design, testing, manufacturing, and calibrating, Interface is the trusted leader in quality load cells. This allows us to keep our finger on the pulse of the marketplace and develop products that meet the unique needs of a wide variety of industries.

From our earliest days, one product that has become truly an industry standard in load cells by popularity and by far the top pick for use in test labs and by product testing engineers is the 1200 Precision LowProfile® Load Cell.

When we originally released our first of its kind LowProfile Load Cell, Interface became an instant market leader in precision load cells.  In fact, our 1200 Standard Precision LowProfile Load Cell, designed for eccentric load compensated tension and compression force measurement, remains our most frequently purchased product every year. This pancake-style load cell is world-renowned for durability, accuracy, and performance.

The 1200 Model Series features and benefits include:

  • Proprietary Interface temperature compensated strain gages
  • Performance to .04%
  • High output – to 4 mV/V
  • 0008%/°F (.0015%/°C) temperature effect on output
  • Low deflection
  • Shunt calibration
  • Barometric compensation

In addition, it’s popularity amongst customers is due to the product’s versatility and customizability. There are multiple models available including the 1240, 1244, 1252, 1260, 1280, and 1290. In addition, the series is compatible with a host of base options, connectors, bridge options and overload protection. And like with all Interface products, our custom solutions team can work directly with you to meet your specific needs.

The 1200 series is used across a variety of industries for test and measurement applications. Included below are a few examples of the product in action expressed as application notes. Industries covered in these examples include aerospace, agriculture, and waste management.

AIRCRAFT LIFTING EQUIPMENT

An aerospace company wanted to check if the valves on their aircraft lifting equipment were working safely and properly. Interface’s recommended installing a 1200 Standard High Capacity Load Cell in between the aircraft testing rig and the lifting jack. The load cell can measure the load’s force safety valve when the lifting equipment opens. Results are then sent to the 9890 Strain Gage, Load Cell, & mV/V Indicator, where the customer can see it displayed in real-time. Using this solution, the customer was able to determine that the aircraft lifting equipment was working properly. Since they are ensured of its safe functionality, it can now be used on real aircrafts that need to be lifted. Read more here.

SILO GRAIN DISPENSING

A customer wants to measure and record the grain being put in and out of their grain dispensing container, as it dispenses content into a carrier truck for transportation. The customer also preferred a wireless solution. Interface suggested installing a WTS 1200 Standard Precision LowProfile™ Wireless Load Cells at the legs of the grain dispensing container. The 1200 can measure the distribution correlation of the grain as it inputted and outputted from the container. Results are transmitted and displayed using the WTS-BS-1-HA Handheld Display for multiple transmitters and logged and graphed using the WTS-BS-4 USB Industrial Base Station. Using this solution, the customer was able to log and graph the measurement results of the grain content that the silo dispenses into the grain dispensing container, and also when the grain is dispensed into the carrier truck.  Get more details here.

WASTE MANAGEMENT CONTAINER WEIGHING

A waste management company wanted to measure the capacity of their waste containers to know when it is time to dispose the waste. Interface provided Model WTS 1200 Standard Precision LowProfile™ Wireless Load Cells to be installed at the bottom of each waste container leg to measure the sum weight of the container. The real time weight data is then transmitted to the WTS-BS-4 USB Industrial Base Station with the supplied Log100 software. Using this solution, the customer was able to determine when their waste container was at full capacity to dispose of the waste, or to transfer it in a timely manner.

To learn more about load cell basics and watch our recorded webinar, go here.

Interface Solutions Designed for Infrastructure Challenges

All infrastructure, big and small, needs to be designed with safety and durability in mind. Take for instance the massive amount of design, engineering and quality control that goes into a suspension bridge requires testing before and after it’s built. Not only does it need to be constructed with supreme accuracy, but it also needs to be tested and monitored constantly to ensure it’s safe for use, especially as often infrastructure projects are exposed to extreme elements.

Among the various tools and technologies used to build and test infrastructure designs, sensors play a substantial role. Interface has served infrastructure industry suppliers and customers since our founding more than 50 years ago. Force and torque measurement products including Interface load cells, torque transducers, load pins, load shackles, tension links and instrumentation are involved in a wide variety of infrastructure applications including construction and maintenance of bridges, roads, transportation systems, communication structures, water and electrical facilities, and numerous inventions that are used to build, test, support, maintain and monitor performance of these critical projects around the world.

Accuracy and reliability of Interface solutions are a key factor in measuring structures and components that are exposed to hazardous or weather-related conditions, heavy loads and constant use. Our precision load cells, rugged load pins, wireless and digital instrumentation, along with multi-axis sensors and robust torque transducers are a top choice for those engaged in infrastructure engineering projects and testing.

A few examples of how Interface products have been used on infrastructure applications over the years are noted below. The following examples are also found with many others here /solutions/infrastructure/. 

Concrete Dam Flood Monitoring

A customer was looking for a solution to monitor a concrete dam and be notified when it reached high flooding levels. Interface provided WMC Miniature Sealed Stainless Steel Load Cells with multiple WTS-AM-1E Wireless Acquisition Modules connected to the load cells. This solution proved to be small enough and perfect for measuring compression and tension on the dam. The WMC Modules are installed on the arch of the dame and transmit data and notify the customer through Interface’s Wireless Telemetry System when flooding occurs. Check out the application here.

Hydropower Turbine Generator Monitoring

When a customer wants to monitor and detect turbine generator faults in their hydroelectric power plant located on a river, Interface can provide a T2 Ultra Precision Shaft Style Rotary Torque Transducer and attach it to the turbine generator with Interface’s Shaft Style Torque Transducer Couplings. When water from the river pushes through the penstock to the outflow, it moves the turbine blades, creating electricity through the generator shaft. Torsion measurements can be graphed and logged with the 9850 Torque Transducer and Load Cell Indicator catching any unusual fluctuations and vibrations. Using this solution, the customer can monitor, graph, and log the torque measurement results of the turbine generator. Learn more here.

Bridge Seismic Force Monitoring Solution

A customer wanted to monitor seismic activity that occurs to a bridge using force sensors to continuously monitor activity before, during and after earthquakes. They also wanted a wireless solution to avoid running long cables on the bridge. Interface provided an LP Load Pin custom made to fit the need. The load pin was used in conjunction with our WTS Wireless Telemetry System to monitor the force on the load without cables. Using this solution, the customer was able to monitor continuously, log results to the cloud and review the data. Read more here.

This is just a brief example of the applications throughout the infrastructure industry that Interface supports. A long list of additional applications that use Interface products includes:

Highways and Bridge Construction and Monitoring

Concrete Dam Measurement and Flood Monitoring

Transportation Heavy Equipment Testing

People Movers for Airports

Train Brakes Testing

Power Generation Equipment

Geotechnical Monitoring

Road Load Tests

Weight Bridges and Transportation Scales

Truck and Aircraft Weighing

Housing Mainframe and Skyscraper Construction Monitoring

Building Foundation Capacity Measurement

Bridge Seismic Force Monitoring

In-Motion Rail Weighing

Cranes and Heavy Object Lifting

Structural Testing and Telecommunication Structures

Conveyor Belts

To learn more about Interface and our solutions for Infrastructure and other key industries, please visit our solutions page at www.interfaceforce.com/solutions/.

Driving Force in Automotive Applications

Among the most highly regulated industries in the world, automotive is up there with the likes of medical and defense. Every component and system needs to be thoroughly tested and deliberately analyzed to ensure that the final product is safe for the driver, other vehicles and pedestrians. Any mistakes or failures can cause catastrophic damage and put lives at risk.

There are hundreds of thousands of different tests that car parts and software go through before they are approved for the road. Among them is force measurement testing. Force and torque tests are integral to the structural and mechanical design and build of the car. Gathering data on the build quality and safety of materials and components found within cars, trucks and more is done through a wide variety of different force measurement testing.

Interface has been a partner to the automotive industry for more than 50 years, from the major OEMs to smaller parts manufacturers and test labs. We build force and torque sensors and acquisition devices designed to provide automotive engineers and manufacturers with high-quality data to monitor and confirm the design and in-action processes of a wide variety of vehicles.

Force testing applications for the automotive industry involve everything from structural, engine, brake, seat belt and suspension tests, all the way down to individual lug nut torque testing.

Recently, Interface has also been supplying solutions to those in the growing electrical vehicle (EV) market. EV cars and other motor vehicles present a wide variety of unique challenges for engine torque and battery technology testing.

As an example of some of the products we offer to the industry, we are highlighting Interface expertise in different automotive applications. This will include specific examples of work we’ve done for our customers recently or in the past.

BRAKE PEDAL TESTING

One of the largest areas of automotive test and measurement we are involved in is brake pedal testing. Our customers need to ensure that applying certain amounts of force to the brake will slow and stop the vehicle as intended.

In this application note, Interface supplied our customer with a BPL-300-C Brake Pedal Load Cell, which was installed on the brake pedal. As the user depressed the brake pedal, force data was transmitted by our BTS-AM-1 Bluetooth Low Energy (BLE) Strain Bridge Transmitter Module to the BTS Toolkit Mobile App and displayed on a mobile device. This allowed our customer to view and graph the data in real-time.

Read the application note for Brake Pedal Testing here.

EV BATTERY TESTING

In the EV market, one of the most integral pieces of technology is the battery used to run every piece of hardware and software in the car. One of the critical tests that’s performed on EV batteries in compression testing. As an EV battery is charged and stores more electrons, it swells. If the packaging that houses the batteries is not intelligently designed to compensate for this swelling, you could have a major problem.

For this challenge, Interface can supply the popular WMC Miniature Load Cell. The load cell will measure compression force as a battery goes through charge cycles on a test stand to determine the force given off as the battery swells. This allows our customers to design the proper packaging for the batteries.

Read more about Interface’s role in the The Future of Automotive is Electric.

SUSPENSION TESTING

A personal favorite of the Interface team is a suspension test we performed on a race car. As you can imagine, race car components need to be finely tuned for optimal performance. The suspension is one of the most significant factors in the tuning process.

Using an Interface Model 1200 Standard Load Cell, we were able to measure simulated motions of a racetrack including bumps, banks and other track conditions. This allowed the customer to gather highly accurate (0.04%) measurements of loads applied to individual suspension points. This type of suspension testing technology can also be performed on a regular commercial automobile, but the race car example is much more fun!

View the race car suspension testing application here.

MOTOR TESTING

In this motor test stand application, it was used in the quality control lab of a major automotive manufacturing customer that needed to test, record and audit the torque produced by a new motor design under start load.

Interface supplied a Model AxialTQ Rotary Torque Transducer that connected between the motor and the differential, on the drive shaft, which could measure and record these torque values. Based on the data collected using the AxialTQ, AxialTQ Output Module, and customer laptop, the test engineer was able to make recommendations to optimize the amount of torque created by the new motor design.

You can read more about the AxialTQ in this post.  

The wide variety of applications for automotive force testing that Interface has been involved in is significant. We have many published application notes beyond those highlighted, including Seat Testing, Engine Head Bolt Tightening and one for an Engine Dynamometer (dyno for short) use case. The examples listed above just scratch the surface.

Interface is a preferred partner to the automotive industry.  To review some of the automotive application notes we have published, please check out our website at /solutions/automotive-vehicle/. You can also give us a call to learn more about the various solutions we offer for customers in the automotive industry at 480-948-5555.