Connecting the planning calendar to your lot size key

First, you will need to set up the planning calendar.
Menu path: Production -> MRP -> Master Data -> Planning Calendar (MD25)
You will then need to use this planning calendar (the one you created) in the material master when planning your raw materials (MRP2 View in 4.6C - Field name : Planning Calendar).
1. When you maintain the planning calendar you will need to enter a valid from date and valid to date.
2. Your periods will also need to be set up and they will be weekly, for example: From Date : 11/23/2001 To Date : 11/29/2001 (11/23 is a Friday, this is your from date). Do this for as may weeks as you wish (say weekly for 2 years).
3. When you have set up the planning calendar, you will then need to make some changes to the weekly lot size configuration (WB), or you may need to create a new lot size key if you do not want to change 'WB'. Essentially, you will need to use the following in the lot size configuration (OMI4) :
No. of Periods : 1 LotSizeProced.: P LotSize ind : K Scheduling : 1
By using the above, you are connecting the planning calendar to your lot size key.