MRP Planning

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Run MRP When Demand Needs A Plan

Use Manufacturing, then Production Planning (MRP) when inventory, manufacturing, and purchasing teams need to decide what to build and what to buy inside a planning horizon. MRP looks at manufactured products with active default BOMs, current stock, allocations, open purchase orders, open work orders, sales demand, run-rate demand, dependent demand from work order components, component availability, vendor setup, lead time, and safety stock when included.

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Choose Planning Inputs

1. Enter the Horizon in days.
2. Turn Include safety stock on when MRP should plan to keep safety stock filled.
3. Click Run MRP.
4. Review the summary cards before selecting rows.

• Products analyzed: active manufactured or hybrid products that have active default BOMs.
• Can build now: suggested work orders with all required parts available.
• Waiting on parts: suggested work orders with one or more component shortages.
• PO suggestions: purchase suggestions that close component or product shortages.

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Read Suggested Work Orders

A suggested work order means Arcus found demand for a manufactured product and a default active BOM that can satisfy it. Each row can show:

• Quantity: the net quantity MRP thinks should be built.
• Start by: the suggested start date based on horizon and lead-time assumptions.
• Estimated cost: the BOM-based planning cost for the suggestion.
• Parts ready: components are available for the suggested quantity.
• Waiting on parts: at least one component is short.
• Demand: the sources that created the need, such as sales orders, forecast, dependent work order demand, or safety stock.
• Open: opens the New Work Order page with the suggested BOM selected.

Select only suggestions the team actually wants to create now. Review floor capacity, open work, due dates, and known vendor delays before creating a large batch.

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Understand Demand Sources

• Sales order demand: open customer demand inside the horizon.
• Run-rate demand: forecast demand derived from historical daily demand.
• Dependent demand: component demand created by Released or In Progress work orders.
• Safety stock: stock target added when Include safety stock is enabled.
• Current supply: available stock, open purchase orders, and open work order supply that offset the need.

If the suggested quantity looks too high, check whether safety stock, run rate, or dependent demand is driving the row. If it looks too low, check whether open POs or open work orders already cover part of the need.

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Review Component Shortages

Rows marked Waiting on parts list the short components. MRP calculates required component quantity from the BOM, scrap factors, and suggested build quantity, then compares it with available stock and open PO quantities. For phantom BOMs, Arcus plans through the phantom parent and surfaces the lower-level components. For normal manufactured subassemblies, MRP can treat the subassembly as a requirement so the team can decide whether to build or buy it separately.

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Read Suggested Purchase Orders

Purchase suggestions are grouped by vendor when records are created. They are meant to close component or product shortages found inside the planning horizon. Each row can show:

• Vendor: the default vendor for the item, when one exists.
• No vendor: the product needs purchasing setup before the draft PO will be useful.
• Quantity: the suggested buy quantity, honoring minimum order quantity when configured.
• Order by: the date implied by vendor lead time and the manufacturing need.
• For: the suggested work order products that created the component need.

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Create Suggested Records

1. Run MRP with the correct horizon and safety stock choice.
2. Review Suggested Work Orders.
3. Select only the work orders that should be created now.
4. Review Suggested Purchase Orders.
5. Select only the purchase suggestions that should be created now.
6. Click Create suggestions.
7. Open created work orders for normal review, approval, release, completion, or cancellation.
8. Open created purchase orders for vendor review, approval, sending, receiving, billing, and close-short decisions.

What Arcus updates:

• Selected work order suggestions become draft work orders using the suggested BOM, quantity, and planned start date.
• Selected purchase suggestions become draft purchase orders grouped by vendor.
• Created records follow normal permissions, approvals, receiving, fulfillment, and accounting behavior.
• MRP refreshes after creation so the same demand is less likely to be suggested again.

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Common Blocks

• No work orders are suggested: confirm the product is active, tracks inventory, has manufactured or both supply method, and has an active default BOM.
• MRP ignores a BOM: confirm the BOM is active, default for the product, and not archived.
• Parts are always short: review component balances, open POs, safety stock, lead times, and whether the component is also manufactured.
• Suggested quantity looks too high: check safety stock, open sales demand, run-rate demand, dependent demand, and whether old open work should be completed or cancelled.
• Suggested quantity looks too low: check open POs, open work orders, and available stock that MRP is counting as supply.
• No-vendor PO suggestions appear: complete purchasing setup for the product before creating the PO.
• Create suggestions returns errors: create fewer suggestions, fix missing vendors or locations, confirm active BOMs, and retry.
• MRP differs from the Reorder Report: MRP includes manufacturing demand and BOM dependencies, while the Reorder Report focuses on product-level reorder signals.

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