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What is Static Error Band Output?

Static error band (SEB) measures the accuracy of a measuring device. Under static loading conditions, it is defined as the maximum deviation of the device’s output from a best-fit line through zero output. SEB includes the effects of non-linearity, hysteresis, and non-return to minimum load.

Static Error Band (SEB) Definition: A band encompassing all points on the ascending and descending curves centered on the best-fit straight line. It is expressed in units of %FS.

SEB is typically expressed as a percentage of full scale (FS), the maximum load the instrument can measure. For example, a load cell with a SEB of 0.1% FS would have a maximum error of 0.1% of its full-scale capacity.

SEB is an essential specification for measuring instruments used to make precise measurements, such as load cells, pressure transducers, and temperature sensors. A high SEB indicates that the device is inaccurate, and its measurements may be unreliable.

How to Calculate SEB

  • Collect a series of calibration data points for the instrument under static loading conditions.
  • Plot the calibration data on a graph, with the instrument’s output on the y-axis and the applied load on the x-axis.
  • Fit a best-fit line through the calibration data points.
  • Calculate the maximum deviation of the calibration data points from the best-fit line.
  • Express the maximum deviation as a percentage of the full scale.

SEB is a helpful metric for comparing the accuracy of different measuring instruments. It is also important to note that SEB is only one measure of an instrument’s accuracy. Other factors, such as repeatability and reproducibility, should also be considered when selecting a device for a particular application.

What is SEB Output?

SEB output is the computed value for output at capacity derived from a line best fit to the actual ascending and descending calibration points and through zero output. It measures the accuracy of a measuring instrument under static loading conditions.

SEB Output Definition: The output at capacity is based on the best fit straight line.

The SEB output is the maximum deviation of the calibration points from this best-fit line. SEB output is typically expressed as a percentage of full scale (FS). SEB output is an essential specification for load cells and other measuring instruments used to make precise measurements.

Why Interface Uses SEB Output Instead of Terminal Output

In the absence of alternate specific instructions, Interface uses the SEB output instead of the terminal output in straight-line scaling of a transducer to a digital indicator or analog signal conditioner. On average, the SEB output line yields the least error over the transducer range relative to the calibrated points.

SEB stands for Static Error Band and is a band on either side of a straight line through zero that is positioned to have equal maximum error above and below the line. The line extends from zero to the SEB output. The line considers both ascending and descending calibration points.

The plot below allows error visualization relative to the SEB and terminal output lines for a typical load cell calibration curve with ascending and descending points.

In this example, the SEB equals 0.03%FS, and the SEB line is no more than 0.03%FS away from any calibration point. The terminal line, in contrast, has a maximum deviation from calibration points of 0.05%FS. The plot shows that the ascending calibrated curve and the SEB line cross near 80%FS, often a more common measurement area in an application than 100%FS.

Source: Levar Clegg

Benefits of Using SEB Output

  • SEB output is a more accurate measure of the load cell’s accuracy than terminal output.
  • SEB output is less sensitive to environmental factors and noise than terminal output.
  • SEB output is easier to understand.
  • SEB output confirms that the measurements are accurate and the results are reliable.

How does a test engineer use SEB Output when selecting a load cell and instrumentation system?

Test engineers use SEB Output when selecting a load cell and instrumentation system to ensure the system is accurate enough for the intended application. The selection of a load cell is often based on an SEB Output that is less than the required accuracy of their application. For example, if an engineer needs to achieve measurements with an accuracy of 0.1%, they will select a load cell with a SEB Output of less than 0.1% FS.

It is crucial to consider the instrumentation system’s accuracy to measure the load cell’s output. The instrumentation system should have an accuracy equal to or greater than the accuracy of the load cell.

For additional information about specification values, be sure to watch this short clip from our Demystifying Specifications Webinar Recap

Test and measurement professionals can select an accurate, reliable, valuable load cell and instrumentation system following these tips.

Our Greatest Resource is Our Team Members

Labor Day is important to Interface. It is our time to celebrate our most valuable resource, our talented team members. We appreciate every single person that has been part of our 51-year-old history. They are what makes us thrive, each and every day.

Our talent is diverse in skills and experience. It takes a wide range of resources to design and build the best precision force solutions in the market place.

At Interface, we are proud of the work we do and the products we provide our clients. Our force measurement tools and technology are recognized as the Gold Standard for accuracy and reliability, because of the hundreds of top-notch engineers, production team members, sales and application engineers, administrators, partners, reps, and distributors, who pour their heart and soul into their work.

On any given day, you can find our experts keenly soldering strain gages, calibrating every load cell, shipping crates of our LowProfile load cells, meeting with clients to design new OEM solutions, engineering new products and supporting our internal and external customers from our headquarter office. It takes a vast group of committed team members to do what we do, and do it well. And that is worth celebrating this Labor Day!

Our employees have been able to achieve success at such a high level because of our focus on the core values we use to define ourselves: ownership, integrity, imagination, and accountability. It’s ingrained in our culture and what we strive to represent throughout the organization.

These values dictate the way our teams interact with clients and one another, and it guides the success of our product development and R&D efforts. There are a shared vision and a common goal which makes collaboration and innovation easier, which helps us to promote a great place to work.

As a premium supplier to the critical infrastructure projects, the aerospace and defense markets, we are also happy to avowal that Interface products are “Made in America.” We take pride in leveraging American labor and contributing our economic success to the U.S. GDP. The National Association of Manufacturing (NAM) presented the following facts on the state of U.S. manufacturing, and Interface is an integral contributor to these milestones:

NAM Facts (Source):

  • Manufacturers contributed $2.38 trillion to the U.S. economy in the fourth quarter of 2018
  • Over the past 28 years, U.S.-manufactured goods exported have quadrupled
  • Manufacturers in the U.S. export nearly half of U.S. manufacturing output
  • Taken alone, manufacturing in the U.S. would be the eighth-largest economy in the world

America’s manufacturing labor force turned America into a powerhouse in the mid-1800s. They started the industrial revolution and became the backbone to American success throughout the next 150 years. It’s critical to our country’s future to celebrate and support manufacturing and labor.

We invite you to check back in every month and read our Faces of Interface blog where we celebrate the individual leaders helping us to achieve our innovation goals. The special series tells the stories and background of some of our most brilliant people. Check out the latest edition here.

Happy Labor Day, and remember to rest and relax. We appreciate all you do Interface Team!