10 Advantages of Magnetic vs. Ultrasonic Fuel Senders

Fuel senders play a crucial role in the efficient functioning of an aircraft’s fuel system, providing essential data to the pilot regarding the fuel level in the tanks.

Among the various types of fuel senders available, magnetic fuel senders stand out for their unparalleled advantages over ultrasonic fuel senders. In this article, we will delve into the numerous benefits of magnetic fuel senders and how they outperform their ultrasonic counterparts in terms of accuracy, safety, reliability, and overall performance.

Are you curious to learn more about how our senders compare to capacitive fuel senders? Then check out our article comparing our magnetic technology to capacitive fuel senders here.

Without further ado, here are the 10 Advantages of Magnetic vs. Ultrasonic Fuel Senders:

1. Fuel Quantity

Magnetic fuel senders are unaffected by changes in fuel composition, so they provide accurate fuel level readings regardless of the type of fuel being used. In contrast, ultrasonic fuel senders can be affected because subtle changes in fuel composition change output, which can lead to inaccurate readings.

2. Fuel Temperature

Magnetic fuel senders are also unaffected by changes in fuel temperature, so they provide accurate readings regardless of the ambient temperature. Ultrasonic fuel senders, on the other hand, can be affected by changes in fuel temperature (changes density), which can also lead to inaccurate readings.

3. Entrained Air

Entrained air is air that is mixed with the fuel in the tank. This can happen when the tank is filled too quickly or when the fuel is sloshing around in the tank. Magnetic fuel senders are unaffected by entrained air, so they provide accurate readings even when there is entrained air in the tank. Unfortunately, ultrasonic fuel senders can be affected by entrained air (changes density), which can lead to inaccurate readings.

4. Contamination

Contamination can occur in the fuel tank due to dirt, debris, or water. Magnetic fuel senders are self-cleaning, so they are not affected by contamination. Ultrasonic fuel senders can be affected by contamination on target or transmitter, which can then lead to inaccurate readings.

5. Fuel Motion

Fuel motion can occur in the tank due to turbulence or turning. Magnetic fuel senders are unaffected by fuel motion, so they provide accurate readings even when the fuel is moving around in the tank. On other hand, ultrasonic fuel senders can be significantly affected by fuel motion, which can lead to inaccurate readings.

6. Safety

Magnetic fuel senders do not have any electronics in the fuel tank, so they are intrinsically safe. This means that they cannot cause a spark, which is important in fuel tanks where there is a risk of fire. Similarly, ultrasonic fuel senders do not have electronics in the fuel tank.

7. Damping

Magnetic fuel senders have a damping mechanism that helps to reduce the effects of fuel motion. This makes them more accurate than ultrasonic fuel senders, which do not have a damping mechanism.

8. Water in Fuel

Water in fuel can occur when the fuel tank is not properly sealed. Magnetic fuel senders are unaffected by water in fuel, so they provide accurate readings even when there is water in the tank. Unfortunately, ultrasonic fuel senders can be affected by water in fuel, which can lead to inaccurate readings.

9. Compatibility

Magnetic fuel senders can be used in existing fuel quantity locations, similar to ultrasonic fuel senders.

10. Output Options

Magnetic fuel senders can provide output in a variety of formats, including frequency, voltage, and resistance. Ultrasonic fuel senders typically provide output in only a ratiometric voltage format.

11. Accuracy

Magnetic fuel senders are the most accurate type of fuel sender available. They can typically provide accuracy of up to 0.75%. Ultrasonic fuel senders typically have accuracy of 3% or less, but sloshing fuel, fuel temperature stratification and fuel foaming present greater accuracy issues.

12. Float Error

Magnetic fuel senders have minimal float error. This is because the float buoyancy does not need to drive a mechanical interface. Simarly, ultrasonic fuel senders have minimal float error.

13. Corrosion

Magnetic fuel senders are not affected by corrosion. Ultrasonic fuel senders are also not affected by corrosion.

14. Fuel Oscillation

Magnetic fuel senders are not affected by fuel oscillation. Ultrasonic fuel senders are affected by fuel foam and vapor effect output.

15. Complexity

Magnetic fuel senders are simpler than ultrasonic fuel senders. This makes them easier to install and maintain.

In the realm of aircraft fuel systems, magnetic fuel senders have clearly emerged as the superior choice when compared to ultrasonic fuel senders. Their unmatched accuracy, resilience to environmental factors, and simplicity in design make them an ideal solution for ensuring precise fuel level readings and promoting flight safety. Whether it’s their immunity to fuel composition changes, temperature fluctuations, or the presence of entrained air, magnetic fuel senders consistently demonstrate their reliability.

Moreover, the intrinsic safety of magnetic fuel senders, without any electronics within the fuel tank, further enhances their appeal for use in aircraft fuel systems, reducing the risk of sparks and potential fire hazards. Their self-cleaning properties and immunity to contamination ensure consistent performance over time, while the inclusion of a damping mechanism effectively mitigates the impact of fuel motion on readings.

Furthermore, magnetic fuel senders provide versatility in output options, allowing for various formats, including frequency, voltage, and resistance, catering to different aircraft systems. The minimal float error and resistance to corrosion and fuel oscillation add to their long-term durability and accuracy.

In conclusion, magnetic fuel senders outshine ultrasonic fuel senders on multiple fronts, proving to be a superior choice in modern aviation. Their precise fuel level readings, safety features, compatibility, and ease of installation and maintenance make them a dependable component in any aircraft’s fuel system. With these advantages in mind, magnetic fuel senders are undoubtedly a critical asset in enhancing flight efficiency and safety, reinforcing their position as the preferred choice for fuel measurement in the aviation industry.

Would you like to view this comparison in a table format? Check out this page to view a table of magnetic vs. ultrasonic fuel senders.

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About CiES Inc.

Established in 2012, CiES is now the largest supplier of aviation fuel quantity probes and senders. They are the recognized leader in the design, development, certification, and manufacture of electronic sensor solutions for original equipment manufacturers, as well as direct-to-market consumer products. Through the creative application of cutting-edge technologies, CiES creates complex end-to-end solutions. This is a company that is changing the game in aviation technology and revolutionizing the way we navigate the skies. Aiming at future growth and innovation, CiES is pushing the boundaries of what is possible.​

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Next Generation Can Trust Their Fuel Gauges.

We’re committed to providing an accurate, safe and reliable fuel level reading, as well as providing you with the highest level of service. Once you have installed magnetic field fuel sensing, your fuel level sensing problems will be solved. When you see the difference, you’ll always choose us for your fuel and liquid level sending needs.