Independent MRP System is referred to as the demand for finished items, whereas, Dependent MRP System is referred to as the demand for subassemblies or part components required for the production of the finished items. Dependent demand is the function of independent demand. The total quantity of part components and raw materials required at a specified time period is the function of the dependent demand. Independent demand is steady when allowances for seasonal variations are executed, but tend to be “lumpy”. Large amounts are used at specific stages in time with no or little usage at other times.
Some of the independent demand items need to be carried on continuously, while some of the dependent demand items need only be stored just before the time they are required in the manufacturing process. The expectedness of dependent demand items indicates there is less or no safety stock requirement.
