Defining Lead Time for Planning

In certain planning situations, lead time is used to approximate the time needed to acquire, make, or receive an item.

In all cases, lead time is defined in these fields on the Items form:

Fixed Lead Time: The number of days from the time the item is ordered until it is received.
Variable Lead Time: Multiplied by the quantity needed to determine the total variable lead time.
Paper Work Lead Time: The number of days it takes to fill out the necessary forms before a purchase order can be started (the time required to convert a planned order into a Released PO). The system sums the Paper Work Lead Time with the Fixed Lead Time and Dock-to-Stock Lead Time when you run the Material Planner Workbench Generation form. This form uses this lead time when determining planned order release dates on the Material Planner Workbench form.
Dock-to-Stock Lead Time: The number of days it takes to get the item into stock after the purchased material is received on the dock. Receiving inspection activity is the usual reason for dock-to-stock planning. The Material Planner Workbench Generation uses this lead time when determining the planned order release dates on the Material Planner Workbench form.

Note: Paper Work Lead Time and Dock-to-Stock Lead Time are also used by the Material Planner Workbench Generation.

This topic describes how lead time applies to purchased items and transferred items. It also describes how to use the Expedited Lead Time functionality.

Where Purchased Item Lead Time is Used

For purchased items, you must specify the lead time values manually in the lead time fields. Purchased item lead time is used to perform these functions:

To calculate the release date of a purchase order when you firm a planned order. The system deducts the item's dock-to-stock lead time from the operation's start date, if not blank, or the job's start date if the operation's start date is blank.
When you cross-reference and create a purchase order from a job material. The system deducts the item's dock-to-stock lead time from the operation's start date, if not blank, or the job's start date if the operation's start date is blank.
When you manually create a purchase order line or purchase order requisition line and an item/vendor cross reference record exists for the item and the PO vendor. The default due date is calculated by adding the item vendor record's lead time to the appropriate date:
- PO line: adds item vendor lead time to PO order date.
- Blanket PO release: adds item vendor lead time to the release date you entered.
- PO requisition line: adds item vendor lead time to the requisition date.
To calculate the due date of safety stock planned orders (current date/time + lead time).

Note: For manufactured items that are not specified as MRP Items, lead time is not used when the system passes parent item requirements down to components. Component due dates are based on the start date of the operation where the component is used (or the start date of the job, depending on the setting of the Plan Materials at Operation Start planning parameter).

Where Transfer Item Lead Time is Used

The system calculates lead time for transferred items in the same manner as purchased items, except it adds the transit time (defined on the Inter-Site Parameters form) to the total lead time. For example, if an item's lead time from the FLT + (VLT * Qty) calculation is 1 day, and it takes 3 days to ship to the receiving site, the total lead time is 4 days.