Real-time measurement of frequency using affordable rotary encoder and LabVIEW

The accuracy of measurements from a rotary encoder is of high importance and the level of accuracy desired will depend on the nature of the application in which the encoder is used. Due to the various errors in the rotary encoder measurement during real-time usage, this work has designed a LabVIEW program that exempts erroneous readings that are not within the chosen range, forms an array of readings within the acceptable range and finds the mean of the array once the size of the array is equal to the chosen size of the array stipulated in the program. This mean value is given as the actual measurement. This gives a more accurate real-time measurement than is the case without the program. A motor-generator set frequency measurements is used to validate the effectiveness of this program and frequency readings on the inverter driving the motor are compared with that displayed on the system through the program. Some analyses are carried out in order to ascertain the dependency of the accuracy of the measurements acquired on the array size utilized in the program.