Digital or Electronic Counter Method of Speed Measurement

Digital or Electronic Counter Method of Speed Measurement Points : Digital or Electronic Counter Method of Speed Measurement The electromechanical methods of measurement of angular velocity are satisfactory up to about a speed of 10,000 rpm. High speed measurements are possible with “digital pickups or counters” which work in conjunction with digital frequency meters.

The biggest advantage of digital methods is that no direct physical contact is required with the shaft whose sped is to be measured. Therefore, no load imposed upon the shaft by measuring device.

The electronic counters, make it desirable to use frequency of out put voltage as a measure of speed. This is because the frequency is not affected by temperature, impedance of metes, and other systematic errors that can affect the voltage readings. Thus the frequency as measured by electronic counters is a measure of speed.

Following are the digital pickups used for this purpose
(a) Photo-electric type
(b) Inductive type.