How the planning run decides what to buy and make
Supply Chain → Supply Plans → Run it: demand, supply, level by level, and what firming a proposal does.
A supply plan looks at what is needed over its horizon, what is already on hand or on its way, and proposes the difference — a purchase for a bought item, a works order for a made one. It proposes; nothing is ordered until somebody firms a proposal.
What counts as demand
- Confirmed and partly delivered sales order lines — only what is still to deliver, on the line’s own date and warehouse. A cancelled or fully delivered line stops counting on the next run.
- Open quotations, weighted, until one becomes a sales order; then the quotation stops counting, so the demand is not there twice.
- Forecast, consumed by the orders in the same period: a forecast of 100 with 80 ordered is 100 of demand, not 180.
- The components open works orders still need, including their scrap.
- Past-due demand lands in the first period rather than disappearing.
What counts as supply
- Stock on hand in the plan’s warehouse (expired lots excluded).
- Open purchase order and requisition lines, each on its own date and converted to the stock unit.
- Open works orders, less what they have completed.
- Proposals already firmed. Firming a proposal into a requisition and running again does NOT propose it a second time.
Level by level
A proposal to make something needs its components, so the run works down the bills of materials: a component used by several products is netted once, after all of them. Each proposal records its level and the parent it serves, so pegging shows why a raw material is needed. Lead time offsets each level by that level’s own lead time; nothing new is started inside the frozen window, and lot sizes (fixed, minimum, multiple, economic) round the quantity up, never down.
A configurable product’s bill of materials holds every variant, so it is never exploded as it stands. Demand that carries a configuration is planned make-to-order from that configuration’s own parts; demand for a configurable product with no configuration is reported as an exception rather than planned from the wrong structure.
Messages
| Exception | What it means |
|---|---|
| past_due | It would have had to be ordered already to arrive in time. |
| reschedule_in | An existing receipt arrives too late; bring it forward rather than order more. |
| cancel | A receipt nothing in the horizon needs. |
| no_bom / no_supplier | A made item with no bill, or a bought one with nobody to buy from. |
| capacity | Work centre hours over capacity in a period (routing hours, not units). |
A what-if (simulation) plan can be run as often as you like and never firmed.
One sales order at a time
Since 14 October, Supply Chain › Supply Planning › Material Requirements Planning explodes and nets a single sales order (or every open one) without running a plan: Raise requisition buys what is short and names the order, Plan production makes firmed planned orders linked to it. Firmed planned orders and the requisitions it raises count as supply on the next planning run, so nothing is proposed twice. See Material Requirements Planning for a sales order.