Counters and tachometers are instruments which are used to measure rotational speed in mechanical systems. Counters are used to measure the number of revolutions that a rotating shaft has made, while tachometers measure the speed at which the shaft is rotating. The output of the counter or tachometer can be in the form of a digital display, a dial, or an analog signal. Counters and tachometers are used in many applications, from motors and pumps to conveyor belts, fans and turbines. Counters can be mechanical, electronic or a combination of the two. Electronic counters use Hall effect sensors, magnetic pickups, and optical or laser-based sensors to generate a signal proportional to the rotational speed. Tachometers use either the same type of sensors, or in some cases optical strips or reflective tape to provide a frequency signal which can be used to calculate the rotational speed.
Counters and tachometers are widely used in industry to monitor the performance and condition of machinery. The most common application of counters and tachometers is in motors and pumps, where they can be used to measure the speed and number of revolutions of the shaft, providing an indication of the performance and condition of the machine. They can also be used to measure the speed of other rotating machines, such as conveyor belts, fans, turbines and more. Counters and tachometers can be used to monitor the performance of mechanical systems, allowing the user to quickly identify any issues and take corrective action.