KA-300 linear scale KA300 Small size Linear Scale with 0.0002 accuracy for metal working – lathes, cylindrical grinders, milling machines, surface grinders. (1) The encoder must be installed with the guide rail of machine tool as thebenchmark and be kept in parallel. The center of encoder measuring range must be positioned on the center of travel of machine tool. Ensure that the actualmeasuring range of encoder is higher than the maximum travel of machine tool.