Use Scheduled Times in Planning

This field applies to MRP and APS.
Note: When you make a change to this field on the What If Planning Parameters form, unlike most planning parameters, it does not automatically change the corresponding field on the Planning Parameters form.

Usually, you run the Scheduling activity to update status and schedule jobs, and then run MRP Planning or APS Planning to create planned orders to satisfy demands based on the current shop floor status and job schedules. When the Scheduling activity schedules jobs, it calculates start and end dates for each of the job's operations and then uses this information to calculate a scheduled completion date for the job, which is saved in the job's Projected Date field.

This field allows you to control whether MRP or APS generates the plan based on the jobs' current start and end dates or the Projected date calculated by the last run of the Scheduling activity.

  • Select this field if you want MRP or APS to plan the due dates of other demands and delivery of supplies around a job's Projected date. In MRP mode, this parameter must be selected if you want to use the Plan Materials at Operation Start parameter.
  • Clear this field if you want MRP or APS to use the current start and end dates defined when the job was initially created or the dates you changed on the job.

You should select this field if your scheduling personnel do not typically fix scheduling problems with jobs, such as scheduling a resource to work overtime or rerouting the job to another machine. This type of business process trusts that the Scheduling program has examined all possible methods for completing a job on time and that you will not manually intervene on the shop floor. In this situation, you want MRP or APS to generate the plan based on the dates calculated by the Scheduling activity because you consider those dates to be realistic.

On the other hand, you should not select this field if your scheduling personnel usually make manual changes on the shop floor to ensure a job is completed on time. In this situation, you do not want MRP or APS to automatically accept the dates calculated by the Scheduling activity. Those scheduled dates might cause related demands and supplies to be late unnecessarily. Instead, you want MRP or APS to use the current job dates that assume on-time conditions. If you find that the late job cannot be moved up and made on-time, you should change the job's end date manually before running MRP Planning or APS Planning so the planning calculations adjust related plans appropriately.

Note: When you change this field, the system resets the dates of all existing scheduled jobs in the existing plan. The next run of MRP Planning or APS Planning will use the appropriate dates for all existing scheduled jobs and newly scheduled jobs.

This field affects only the start and end dates for the scheduled job, not any other data associated with the job, such as operation start and end dates. Therefore, if you clear this parameter, the dates of detailed resource usage for a job considered by MRP or APS may not correspond exactly with that job's start and end dates. However, the overall resource load will be consistent and correct and will not affect the planning calculations.