To measure the number of revolutions of the engine, a device called a tachometer is used. This device measures the frequency of rotation of parts of mechanisms per unit of time or linear speed. Depending on the type of device and the object of measurement, both contact and non-contact measurements are possible. There are various types of tachometer design, but they have a common principle of operation.
Necessary
Tachometer
Instructions
Step 1
Understand how the tachometer works. The number of revolutions is counted by registering the number of pulses that come from a special sensor. The duration of the pause between pulses and the order of their arrival are also taken into account. Some devices of this type are universal and can be used for other purposes, for example, for counting products on a conveyor, running machines and mechanisms. For example, consider how to measure engine speed with a device such as IO-10 or IO-30.
Step 2
Before starting the measurement, set the device to the desired speed range. To do this, press the arrow control button, and then by longitudinal movement of the drive shaft, turning it, set the range indicator to the required limit.
Step 3
If the range is unknown, set the tachometer to the upper limit. Then, when starting the measurement, make sure that the arrow does not deviate; in this case, set a smaller range of values, up to the required one. It is not recommended to measure engine speed above the permissible limit, as this can lead to damage to the tachometer.
Step 4
Use the external and internal scales of the device to read the shaft speed. If necessary, use the scaling of the measures by multiplying them by 10 (if the range is 250 - 1000), or by 100 (on the range 2500 - 10000).
Step 5
To take a measurement, slide a rubber or metal tip onto the tachometer shaft. If access to the center of the shaft is difficult, attach a special extension to the tachometer shaft. Press the handpiece against the center of the rotating shaft for 5 seconds. Note on the scale of the device the value of the device where the arrow stopped.
Step 6
If it is necessary to change the measuring range, be sure to first disconnect the tachometer from the motor shaft. Then change the parameters with the range switch by rotating it around the axis of the drive shaft. Release the arrow button to reset the measured value.
