How modern fuel dispensers work?
Mac 15 2021-11-26 16:26:57
An electronic fuel dispenser pumps the fuel from an underground tank passing into a measurement transducer, responsible for the measurement, throughout the nozzle, under the control of a solenoid valve, to the car tank. The measurement transducer consists of a mechanical axis integrated into a fuel dispenser pulser, which converts the movement of the axis in electronic pulses. Consequently, the number of pulses is proportional to the measured volume.
Under normal circumstances, fuel dispensers, for example
fuel dispensers, are very precise and accurate measuring instruments.
Some fuel dispenser models also include features to increase information security (e.g., fuel dispenser pulsers can provide the measurement's digital signature). Besides, fuel dispensers also present a high automation level. They commonly integrate with payment or data gathering systems. Due to their embedded technologies, modern fuel dispensers are in practice fuel smart meters, and we can classify them as IoT devices. Fuel dispensers are subject to subsequent verification, i.e., they are periodically tested and compared to volume standards by applying procedures based on general recommendations. They are also subject to metrological field surveillance. The equipment is tested randomly in the field, and notified bodies check its compliance with legal requirements. According to the International Organization of Legal Metrology (OIML), the test of accuracy comprises testing the instrument in different flow rates using a standard capacity measure. For example, in Brazil, tests follow the recommendation of using a 20 liters standard, and the maximum permissible error is 0.5%, for both maximum and minimum flow rate. Devices that do not fulfill the requirements are rejected and shall be removed from use. In Mexico, notified bodies adopt the same maximum permissible error of 0.5% in field surveillance, although other processes (e.g., type approval) can demand errors no higher than 0.25%.