Item data refers to the planning factors necessary for the planning and scheduling tools of master scheduling and MRP. Most of it is static and is stored in the computer’s item master file. It includes things like lead times, order quantities, safety stock/time, shrinkage factors, scrap or yield factors (stored in the bill of material).
Getting the item data collected and loaded is a necessary step, but it’s normally not a big problem. The people doing it should be primarily the same ones who’ll be operating these planning systems: the master scheduler(s), material planners, and distribution planners. They’ll need education, time to do the job, and some policy direction.
Wherever practical, use the numbers already available. Review them, make sure they’re in the ballpark, and fix the ones that are obviously wrong. If the lead time for an item is too high or too low,change it to a reasonable number; otherwise, leave it alone. If the order quantity for a part is out of line, change it; if not, let it be. If an item routinely experiences some scrap loss in production, add in a scrap or shrinkage factor. Otherwise, leave that factor at zero.
The subject of using the numbers already in place leads to a larger issue. When implementing ERP, change only what’s absolutely necessary to make it work. Don’t make changes for incremental operational improvement unless they’re also necessary for implementation. They’ll be plenty of time later, after the system is on the air, to fine-tune the numbers and get better and better. There are two reasons for this—people and diagnosis: