The fuel level sensor Epsilon is designed for precision (with accuracy < 1 %) measuring the level of fuel in the tanks and the tanks of vehicles. The sensor can be used as part of control systems for fuel consumption and systems of satellite monitoring of vehicles (GPS/GLONASS) of different manufacturers. Measuring principle the sensor Epsilon relates to capacitive type.
Unique differences from the sensors of other manufacturers:
- High precision measurement of fuel level due to the higher resolution sensor level and the best linearity of the measurement scale;
- Tech modular design (measuring head is mounted and dismantled independently of the fuel probe, which allows, if necessary, easily and quickly change the measuring head without re-calibration of the tank);
- The ability to use short probes (for flat tanks with depth less than 30 cm);
- Light weight (300 g) and ease of installation.
The sensor device
In the measuring head of the sensor is a level Converter, the digital signal processing circuit, the data exchange device, the voltage regulator and the scheme that provides the necessary protection input and output circuits. Connection with external devices is provided through the interface cable.
Measurement of fuel level is provided by the measuring head together with the probe immersed in the fuel. The probe is a coaxial capacitor formed by an aluminum tube (outer electrode) and insulated copper wire (inner electrode). The required string tension is supported by the spring in contact probe connector.
The mounting of the sensor is performed using self-drilling screws to secure the sensor flange (with gasket) on the tank. The tightness of the landing of the measuring head is provided with sealing ring located in the end groove.
Protection of the interface cable from mechanical impact is provided by a flexible metal hose.
The safety sensor is provided with application:
- intrinsically safe measuring circuit with predetermined values of voltage, inductance, capacitance and resistance;
- multilevel protection of the supply and interface circuits;
- the metal shell of the measuring head with a proper degree of protection (IP-68 on GOST 14254);
- filling compound sheath of the measuring head.
The principle of operation
Sensor probe when immersed in fuel functions as a variable capacitor whose capacitance is linearly dependent on the level of its filling with fuel.
The measuring head of the sensor performs a linear transformation of the probe capacitance into a digital code of fuel level, the processing of the received digital data with averaging of measurement results, the temperature measurement of the fuel tank and a results data in a standardized Protocol EDE via RS-485 or RS-232 or analog signal (only the level), depending on the model.
Data about the fuel level may be issued in the form of 10 -, 12-or 16-bit value temperature data – in the form of 8-bit values.
Calibration tank
To ensure accurate control of fuel amount is performed, the calibration tank is initially empty (full) the tank is filled (drained) equal portions of fuel with the help of special software eS Install measurement and fixing of the sensor after adding (drain) of each portion.
The result of calibration in the calibration table of tank and the credentials of the work performed is saved in PC format, ensuring data transmission in the control software.