The maximum net depth of water per irrigation is defined by how much water a soil can hold without losing it to leaching. If the soil is full of water, the crop can use this much water before it is stressed. The move interval assumes a maximum set time on only 12 hour intervals because it is less work. A good estimate for a set-move sprinkler ranges from 50 - 75%. The suggested nozzle diameter assumes that the nozzles are in good condition, and are all the same (All DuCaR Sprinklers come with FREE nozzles suitable with the sprinkler).
Reference: Washington State University