how does a tachometer work

• 2022-04-19

There is a crankshaft speed sensor on the engine, which will send a pulse signal with the operation of the engine crankshaft ( some gasoline engines may take the ignition pulse signal ). The signal is transmitted to the engine computer, and after calculation, the output adjustment signal is transmitted to the tachometer to adjust the operation of the driving stepper motor on the tachometer ( the pointer is directly installed on the rotating shaft of the stepper motor ) . The faster the engine speed, the more pulses will be generated, and the greater the speed value displayed on the instrument . In order to accurately display the speed, the stepping motor only needs 1 / 3 degree in one step.

The oil pressure sensor transmits the pressure of the oil in the oil passage to the sensor, and the instrument is driven by the pulse current to display the engine oil pressure. The water temperature sensor transmits the temperature of the coolant flowing regularly in the engine cylinder to the transistor in the sensor, which is displayed by the instrument. The oil control sensor, which is configured on each fuel injection nozzle, is the function of controlling the amount and concentration of fuel injected and excessive return oil. The turbocharger sensor is the opening device for setting the engine speed.

During driving, try to keep the speed of the engine below the red scale of the tachometer. It is strictly prohibited to overload the engine. In addition, do not drag the vehicle with manual gear as far as possible.

The engine needs to be preheated before cold start. Only by ensuring that the engine works at normal temperature can the running resistance, wear and working stability between its parts reach the best state.

When one third of the fuel in the fuel tank is left, it is necessary to refuel immediately to make the gasoline pump in the fuel tank dissipate heat well and ensure that the gasoline pump has a long enough service life.

Use fuel that meets the regulations. Inferior gasoline will cause a large amount of carbon and glue to accumulate in the combustion chamber , fuel injector , air inlet and valve , resulting in unstable idle speed and difficult acceleration of the engine. Therefore, we should pay attention to the quality of fuel.