How to calibrate the fuel tank level gauge

Pressure regulation method: Under normal operating conditions of the engine and three-way catalyst, controlling the airflow of the fuel tank switch can sometimes make the fuel gauge reading accurate. 
Calibration of liquid level gauge: For the calibration of liquid level gauge, zero point calibration is first required to determine the output value of the liquid level gauge under no-load state. Then perform range calibration to determine whether the output value of the liquid level gauge is accurate throughout the entire measurement range. Finally, repeatability and stability tests are conducted to verify the measurement performance of the liquid level gauge.
Static calibration method: Calibration is achieved by measuring the reference point of the known liquid level on the level gauge, and then comparing it with the height measured by the level gauge. This method is applicable to most types of level gauges.
Comparative calibration method: Compare the value measured by the level gauge with a known accurate value, suitable for high-precision level gauges. Determine error 3 by comparing the reading of the liquid level gauge with the known liquid level height.
Dynamic calibration method: Calibration is performed by measuring the response time when the liquid level rises or falls using a level gauge. This method usually requires the use of a unified standard flow rate for control.
Inhalation calibration method: The liquid level is measured by applying negative pressure above the level gauge, and the accuracy is determined by comparing the reading of the level gauge with the liquid level height under known negative pressure.
Hook calibration method: suitable for some special level gauges, such as hook type level gauges. Calibration is carried out by hanging a known mass object on the liquid level gauge and measuring the difference between the reading of the liquid level gauge and the mass of the object.
Linear calibration method: suitable for certain types of level gauges, such as pressure level gauges. Determine the linear relationship by injecting liquids of different heights into different positions and measuring the readings of the liquid level gauge.
Differential pressure calibration method: suitable for level gauges that use pressure sensors for liquid level measurement. Calibrate by applying pressure at a known liquid level height and measuring the reading of the liquid level gauge.
Frequency calibration method: suitable for certain types of level gauges, such as ultrasonic level gauges. Determine the liquid level height by measuring the propagation time of ultrasonic waves and compare it with the reading of the liquid level gauge for calibration.