Encoder pulse number selection

It can be calculated like this, you must first determine the maximum operating speed of the membrane per second (such as 500MM/S). And what is the highest frequency of the collection you count (for example, 30KHZ). So you can calculate the circumference of the measuring wheel 75*3.14=235.5MM, so use 500/235.5=2.123, which is the number of turns per second. Then use this number of turns * pulse number of the encoder not to exceed 30KHZ.