Preserving Inventory and Supplies for Short-term Demands
This topic applies to APS. In some situations, demands may consume inventory and
planned supplies earlier than necessary, causing shorter-term demands (for example,
demands planned using Get ATP/CTP) to be late. For manufactured, purchased items, you
can use safety stock, as well as the Time
Fence Rule for the item.
A time fence rule determines a boundary of time for preventing longer-term demands from consuming inventory and supplies. Demands due later than the time fence cannot deplete available inventory and supplies below a preservation level, which is based on the item's Safety Stock level.
Note: Safety stock orders are never planned sooner
than the time fence. In addition, time fence is suspended during Get ATP/CTP.
Valid Time Fence Rules are:
- Lead Time: The length of the time fence is defined by the end item's lead time (Fixed Lead Time + (Variable Lead Time x order quantity)). If a PCAL shift is defined, the system calculates lead time according to that shift. Otherwise, it calculates lead time using 24 hours x 7 days a week. Select this option if the time to replenish this item's quantity should be represented only by the end item lead time.
- Accumulated Lead Time: The length of the time fence is defined by the accumulated lead time for the end item + the lead times for all of its component items. If a PCAL shift is defined, the system calculates lead time according to that shift. Otherwise, it calculates lead time using 24 hours x 7 days a week. Select this option if the time to replenish this item's quantity should include the lead times of all the components (that is, the components may not typically be available).
- Specific Value: The length of the time fence is defined by the value in the Time Fence Value field (in days). The system calculates lead time using 24 hours x 7 days a week.
How APS Planning Uses the Time Fence
The system applies the time fence only during the pull-planning phase of APS Planning. If the system fails to plan the demand using pull planning, and must switch to push planning, it ignores the time fence and uses whatever inventory and supplies are necessary to satisfy the demand as soon as possible.