Indian Engineering Students Recognize the Significance of Magnetic Field Fuel Level Sensing

As I was doing presentation research a potential automotive client and I ran across an undergraduate paper in engineering that listed our technology as a system to utilize for fuel level measurement on engineering project cars - complete with a picture of our aviation sensor system.

I was encouraged  -  The next generation of engineers seem to easily embrace the difference and improvement  AMR sensing provides to fuel level.

Fuel Level Paper

Every day in the lab and every day aircraft owners see the benefits that accurate fuel level provides, and shake our heads at the level of accuracy we have become used to in our cars.

In preparing my meeting notes,  I made the realization that the current resistive technology has remained unchanged in our gas or diesel vehicles for 85 years.

It is probably the only system that a pioneering automotive engineer of the early 20th century would recognize and understand on a modern automobile


The carburetor left current production cars in 1990 and in light trucks in 1994.

It's time to throw the old potentiometer fuel level  to the curb.

Float Based Sensors - Accuracy Quality Reliability

Float Based Sensors 

These sensors have been in use for a long period of time.  They have a few advantages that are difficult to overcome.   If they have a less than stellar reputation it is more about the electronics used, than the method  of finding a fluid level.    We will assume that quality and good practice

• The float will find the surface 

• Provides a reliable value for full and empty
• Provides a stable output, even under fluid agitation.

• Simple mechanism and controlled motion about a pivot.

• Used everyday in the most critical applications 

• Independent of fluid type or composition

• The singular most popular method for measuring liquid level 

• A float and pivot arm can be maintained for millions of operational cycles 

The typical methodology for finding level is resistance - either in a wound wire or a resistance grid.  The output is simply a distinct resistance value.  However this mechanical method for obtaining an electrical value for fluid level has a few problems.

• This practice introduces a mechanical wear item into the system.  It is this wear on the resistance surface that draws the most criticism.

• The CIES Inc float sensor design has only a pivot to wear - and we can utilize a lighter float as there is limited friction to overcome.

• Resistance needs electrical modification to correlate with volume 

• The CIES Inc. float sensor design is digital output and can be programmed to tank volume 

• Resistance circuits immersed in fluids are susceptible to corrosion from alcohol in gasoline or de sulfered diesel or potentially to the 100LL replacement.

• The CIES Inc. float sensor design sensing element is outside of the fuel compartment no chance for corrosion 

CIES Inc answered the quest  - What if we could combine the simple and effective elements of a pivoted float and replaced the resistance element and its problems from the fuel tank sending system

Only CIES Inc has a patent to combine a sophisticated, reliable and stable sensor technology to a simple float mechanism.

CIES FUELRITE Level Sensor 

Utilizing the patented Anisotropic Magneto Resistive technology allows CIES Inc in an intrinsically safe non contact system.

CIES Inc  effectively married the simplicity and effectiveness of the float based system with a non contact level sensing technology with the following characteristics:

• Effective 
• Accurate
• Sensitive - Measures down to 0.02 Degrees 
• Immune to nearby magnetic fields
• No hysterisis -
• No drift over time or temperature - stable 
• Intrinsically Safe 

A proven system backed by exhaustive testing. 

Let us know your unique application

Contact Us

Fuel Level Senders - Automotive

Fuel level sending has been the providence of electrical resistance since somewhere in the 1930's when electrification of the automobile hit full stride.  The Ford Model A used a very clever sight gauge so that you actually saw a liquid representation of fuel level - neat design but expensive.

http://www.facebook.com/Fuellevel

Resistance Level worked very well and was easy to understand  -  X Ohms Full - Y Ohms Empty

Simple

And then suddenly somebody decided to add alcohol -  to fuel -

Methanol and ethanol contain soluble and insoluble contaminants.[5] Halide ions, which are soluble contaminants, such as chloride ions, have a large effect on the corrosively of alcohol fuels. Halide ions increase corrosion in two ways: they chemically attack passivating oxide films on several metals causing pitting corrosion, and they increase the conductivity of the fuel. Increased electrical conductivity promotes electrical, galvanic and ordinary corrosion in the fuel system. Soluble contaminants such as aluminum hydroxide, itself a product of corrosion by halide ions, clogs the fuel system over time. To prevent corrosion the fuel system must be made of suitable materials, electrical wires must be properly insulated and the fuel level sensor must be of pulse and hold type (or similar). In addition, high quality alcohol should have a low concentration of contaminants and have a suitable corrosion inhibitor added.

So if you turn to any car chat blog (ANY CAR CHAT BLOG)  -

Failed fuel level sensors are driving OBD II cars to the shoulder.

So we need to find a replacement  Smiths (Stewart Warner, VDO, Veglia, Et al) in a Pulse and Hold fuel senders - Not compatible 

We are producing  a patented new non-contact fuel level sensor.

We are applying the sensor presently  to aviation (aircraft, rotorcraft) - In aviation we don't have alcohol,  but we can't put wires in the tank - something about electricity and fuel

Aviation  requires - what cars - all cars using Alcohol mixed fuel need - A non contact fuel level sensor

It is also helpful in this environment 

Fuel Level Sensor Under Test

We use a new concept in our sender called Magnetoresistance - certain materials change resistance in the presence of a rotating magnetic field and they can do this from as far as 3/8" away actually from the dry side of the tank.

Most of us see this everyday in the compass on our smartphone

There is no pivot or contact resistance,  so the float can be smaller and the range can be larger (fuller fulls and emptier empties)

Neat thing is that the  output of this sensor  can mimic a resistive sensor

Hey if you find this interesting let us know

scott.philiben@ciescorp.com