Why Frequency Output for Fuel Level Indication?

CiES initially adopted a frequency output for their sender units in response to Cirrus’ specific requirements.

Cirrus was utilizing the Garmin GEA71, which already had its analog inputs fully engaged. The consensus between Cirrus and Garmin was that a digital signal would enhance fuel quantity measurement. With over a decade of use, CiES has validated the decision to use frequency signals for several compelling reasons:

  1. Compatibility: Frequency signals align well with the outputs from capacitance fuel sensors, making them applicable across different fuel quantity signal systems.
  2. Noise Immunity: Unlike analog signals that are vulnerable to noise interference—unwanted voltage variations that can cause processing errors—digital frequency signals are resistant to such disturbances. This is especially beneficial for data transmission over long distances, such as from an aircraft’s wing to the cockpit, where analog signals can degrade and lose quality.
  3. Simplicity and Diagnostics: Frequency signals are straightforward to measure using standard digital equipment, such as a digital multimeter, and require no physical alterations to the microprocessors, only software updates. The focus on easy diagnosis and cockpit integration was central to the design of CiES’s new fuel quantity sensor system, which was also designed to seamlessly replace the existing sensors in aircraft.

Today, CiES is a leading supplier to the aviation industry, equipping a large share of new aircraft globally with their digital signal technology. This achievement underscores the industry’s shift toward digital frequency as the norm for future systems.

Despite the prevailing industry perception favoring traditional large aircraft technology, CiES has consistently surpassed other fuel quantity measurement technologies in the market, especially in Original Equipment Manufacturer (OEM) applications. CiES’s proven performance has solidified its status as the go-to provider for General Aviation (GA). Finally, with the evolution of fuels in GA expected to influence capacitance measurement significantly, CiES’s digital frequency interfacing technology positions itself as a forward-looking solution for fuel measurement systems.

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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.