planning time fence: basically it is the period in which no changes to the plan happens automatically through MRP run
inhouse production time: the time required to produce a material in calender days
Pld delivery time: time required to procure a material if it is procured externally.
the latter 2 values are of significance in scheduling the delivery dates. inhouse production time for the product and PDT for the components(sourced externally)
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Planning time fence
The planning time fence specifies a period within which no automatic changes are to be made to the master plan.
The planning time fence is maintained in workdays.
It is only used for materials that are planned using an MRP type which includes a firming type.
The firming type determines how order proposlas are to be created or scheduled within the planning time fence.