Analog Tachometer Signals

By synchronizing the tachometer and sound or vibration acquisition channels, you can acquire the analog tachometer signal with the same DAQ device that you use to acquire sound or vibration signals. Some DAQ devices might have difficulty acquiring very high rotational speed signals from tachometers or from encoders that generate hundreds of pulses per revolution. Even if you choose a DAQ device that can sustain high enough sampling rates to provide sufficient resolution for the tachometer signal, sampling the sound or vibration signals at the same high rate is not efficient because of the demands that synchronization places on the measurement and computational effort. In this case, you cannot acquire the tachometer signal with an analog measurement channel. Instead, you can avoid unnecessary computation and system resource expenditure by running the acquisition of the sound or vibration signals at a lower frequency and by using a counter device to acquire a digital tachometer signal.