Capacitive fuel level sensor, also known as Capacitive Fuel Level Transmitter, Capacitive Fuel Meter… are a kind of liquid level sensor operated by two electrodes made from two parallel metal plates that are insulated by a non-conductive material. So, what are they and how do they benefit us?
First of all, Fuel level sensor is a device to indicate the level of the fuel in fuel tank fitted a vehicle (trucks, containers, vessels). They will have functions to transfer signal to GPS Tracker Device (through some types of signal as analog, frequency, RS232, RS485) and being synced to fleet management platform of fleet owners.
The advanced platform will sum up and provide a lot of information on the dashboard display such as information about real-time consumed fuel level, speed fuel economy, speed… Nowadays, the float type with Thick Film Resistor(TFR) and Reed switch type fuel level sensors are being used most popularly. However, in a position of a fleet owner requesting a real-time accurate tracking information, this type exposes many limitations like nonlinearity, fluctuating output due to motion, output variations in steps …. Therefore, it is vital to have a sensor with better reliability, accuracy and adaptability.
Capacitance technology based level sensor is identified for development as one of the solutions to meet the demands of the above requirements. Basically, capacitive fuel level sensors are operated by two electrodes forming a capacitor, often in the form of two parallel metal plates that are insulated by a non-conductive material. capacitors store electrostatic energy in an electric field. The capacitor’s ability to store this energy (a measurement known as “capacitance”) increases especially when the volume of insulating material increases.
When built in fuel meter, capacitors work by processing capacitance with reference to the dielectric constant of the material being measured and the voltage being used to complete the circuit. These measurements are used to determine fuel levels. Higher levels of dielectric material result in greater capacitance.
In addition to the wide range of materials and applications capacitive level sensors are capable of performing with, they also have the advantage of being mechanically simple with no moving parts and minimal required maintenance. In addition, they’re well-suited for both point and continuous level measurements and are resistant to agitation.
Advantage: The advantage of a capacitive type fuel level probe is that there are no moving parts and can be used to replace the vehicle own fuel sensor directly without extra hold drill. It is also cutable to suit different tank length. Other benefits can be high accuracy, durability, reliability and available at low-cost.
Disadvantage: The disadvantage is that the gauge must be calibrated when being installed. It required a little time, patience and experience (from choosing drilling position to configuring the software).
However, due to the fact that capacitive fuel level sensor is based on simple principle, there are many brands building it with little effort. This results in low-cost and also low-quality sensor because of being mass-produced without controlling the quality. To maximize the advantages, a good fuel level sensor will require high-class components (such as circuit board, aluminum probe, protection glue, signal wire…) and a well-configured software. It should also be easy to install, fix and replace.
In reality, there are some brands you can take into account when considering purchasing fuel level transmitter for your fleet such as Omnicomm, Technoton, SOJI, Escort… For example, SOJI Fuel Level Sensor offers a very good performance per cost with high accuracy (>99.5%), high durability (up to 5 years) and well compatible with top GPS brands (Queclink, Teltonika,…)