Glossary
WMS
Warehouse Management System
The system that knows where physical items are inside a building and directs the movements between those locations.
A WMS manages locations, putaway, picking, replenishment and stock counts. Its contribution is granularity: an ERP is generally content to know that forty units exist, while a WMS knows which shelf each one is on and directs someone to the right one.
The dividing line with an ERP is ownership of the location. Once storage has addresses and movements are confirmed by scanning, a warehouse system is doing the work, whether it is a separate product or a module of the ERP.
Repair operations put unusual demands on it, because the same building holds several kinds of stock at once: incoming equipment awaiting triage, devices in process, harvested parts, new spare parts, finished goods and waste awaiting collection. Those have different owners, different regulatory status and different valuation rules.
The item that breaks naive setups is the harvested part. It has no purchase price, it came out of a specific device, and its availability is a consequence of dismantling decisions rather than of purchasing. Tracking it properly is what makes the difference between a parts store and a pile.