Modern vehicles have more sophisticated models of tachometers – digital and analog, showing the instantaneous speed of rotation. All rate information is displayed on the electronic LCD display. Their principle of operation is based on registration of the number of pulses coming from the sensors, the sequence of their receipt and pauses between pulses.
In the digital tachometer includes the Central processor, the sensor temperature of the liquid, the chip reset of the processor, ADC, 8 digits, LCD panel and the optocoupler diagnostics of the valve of idling. Tachometers of this type are usually made in the form of electronic display, which displays all the information – the number of revolutions of the engine and the shaft.
So, to read the rpm with a laser digital phototachometer on the rotation object is glued to a special reflective label included in the kit. In operation the laser beam is reflected from the marker, and the signal is read with a sensor device. Digital tachometer is indispensable in the adjustment of electronic blocks of ignition of engines mounted on vehicles.
Analog automotive tachometers more convenient. The readings reflect moving the dial hand. It consists of a magnetic coil, a chip, a graduated scale, arrow and wire. The analog tachometer is a device in which the signal from the shaft is transferred via wires to the chip, and that, in turn, leads to the movement of the arrow on the graduated scale.
The testimony of the tachometer transformirovalsya, as a rule, in certain values – hours, minutes, seconds, meters, etc. the Most accurate electronic enable measurement of up to 100 rpm According to the method of installation of tachometers are divided into regular and remote. So, if regular devices are mounted directly into the dashboard, remote control, installed on a special stalk on the torpedo panel. In some newer models of cars use tachometers which applied a stroboscopic effect is achieved by using a bright flash lamp.