You need an App, forecast on another Location or Firm Planned Orders to keep the Long Term requirements

If you use planned production orders as the demand for long-term MRP planning on purchase items in Business Central, you need to know that running the planning worksheet on production items will delete planned production orders outside the planning interval. This is standard behaviour out of the box.

You have three ways to handle this. You can agree with your master planners not to touch the planning worksheet until your long-term planning is done, but this forces everyone to work in time blocks and is not a good solution. You can place your forecast and long-term planning on a separate location, since MRP plans per location and per item, so production orders on other locations are not deleted. Or you can install an app from AppSource that keeps the planned production orders outside the planning interval intact.

The recommended approach is the app, because it solves the problem cleanly without forcing workarounds on your planners.

Using planned production orders as demand for long-term MRP planning

The easiest and best way to do long-term requirement planning is to use the planned production orders as the demand for your MRP planning on purchase items. This gives you a clear basis for planning purchases far into the future.

In a typical setup you will see a list of planned production orders with dates spread across the calendar, including orders placed in the autumn and late in the planning horizon. These are your long-term planned production orders, and they drive the requirement for the items you need to purchase.

Why the planning worksheet deletes planned production orders in Business Central

There is one issue you need to be aware of, and it is a little unfortunate in Business Central.

Your master planners will also use the planning worksheet for their production items. They run a plan prepare for production items, but only within a specific period. Within that shorter interval they want to handle all the firm planned and released production orders.

The problem is that when you plan on an item per location, Business Central deletes all the planned production orders out of the box, including those that fall outside the planning interval. So when your master planner runs the planning worksheet, the long-term planned production orders you set up as demand are deleted along with everything else.

Three strategies for protecting your long-term planned production orders

You have three options for handling this.

• Coordinate the timing. You agree with the master planners not to touch the planning worksheet until you have finished your long-term planning. This is a bad strategy, because it forces everyone to schedule their planning into rigid time blocks.
• Separate the locations. You make your forecast on a dedicated forecast location and run the long-term requirement planning on another location. Because MRP planning works per location and per item, the planned production orders on the long-term location will not be deleted when the master planner runs the worksheet on their own location. You filter the planning worksheet on specific locations, and you only need to change the location on the production orders when they move into the master planning interval.
• Use an app. You install an app from AppSource that handles this nicely in Business Central. The app does not delete planned production orders that lie outside or on the other side of the planning interval.

Recommended approach

The app is the best option. It solves the deletion problem directly without forcing your planners to coordinate timing or to manage extra locations manually.

Q&A