Sometimes it is necessary to determine the frequency of rotation of the crankshaft of the internal combustion engine on the different modes of its work or for example, the frequency of rotation of a shaft of the electric motor under various loading. For each case there is the most suitable way of determination of this parameter.
It is required to you
- electromechanical tachometer, electronic automobile tachometer, arrow mechanical hour tachometer.
Instruction
1. For control of frequency of rotation of the crankshaft in the internal combustion engine by means of the electromechanical tachometer connect its sensor to the ratchet mechanism of the crankshaft and connect the power supply of 12 Volts to the tachometer. Start the car engine. Changing the frequency of rotation of the crankshaft for achievement of the necessary modes, read out its value from the sensor of the electromechanical tachometer. At application of this way the approximate frequency of the crankshaft as the error brought by an imperfect design of this tachometer is high is defined.
2. For more exact determination of frequency of rotation of the crankshaft connect an alarm entrance of the electronic automobile tachometer to a conclusion of the coil of ignition connected to the breaker of the distributor of ignition of the car. Connect food of 12 Volts to the electronic automobile tachometer. Start the car engine. Changing the frequency of rotation of the crankshaft in necessary limits, read out its indications from the display of the electronic tachometer. This way has high precision.
3. For determination of frequency of rotation of a shaft of the electric motor read this value in the plate placed on the case of the electric motor. If the plate is absent or the inscription in it is jammed, turn on the electric motor. Bring to an axis of a shaft and concern its sensor of the hour mechanical tachometer. Without tearing off the sensor from an electric motor shaft axis, press the Start-up button on the case of the tachometer. After a stop of the movement of an arrow consider indications of frequency of rotation of a shaft of the electric motor opposite to it. Then press the Dumping button for return of the tachometer to a former state. If necessary repeat measurement. This way has the average level of accuracy, is limited to a mechanical design of the arrow mechanical hour tachometer.