Buffers
A buffer is a (logical of physical) inventory point for an item at a certain location.
Different types of buffers exist:
- Default:The default buffer uses an “producing” operation to replenish it with additional material.
- Infinite:An infinite buffer is unconstrained and has an infinite supply of the material.Propagation through a bill of material will be stopped at an infinite buffer.
Field |
Type |
Description |
|---|---|---|
item |
item |
Item being stored in the buffer.
The combination item+location+batch is the unique primary
key of this table.
|
location |
location |
Location of the buffer.
The working hours and holidays for the buffer are taken
from the available calendar of the location.
The combination item+location+batch is the unique primary
key of this table.
|
batch |
string |
Blank, unused for make-to-stock items.
Batch identification for make-to-order items.
The combination item+location+batch is the unique primary
key of this table.
|
description |
string |
Free format description. |
category |
string |
Free format category. |
subcategory |
string |
Free format subcategory.
If this field is set to ‘tool’, the field ‘tool’ will
automatically be set to true.
|
onhand |
double |
Inventory level at the start of the time horizon.
Default is 0.
|
minimum |
double |
Desired minimum inventory, aka safety stock.
Use this field if the safety stock doesn’t change over
time.
The solver treats this as a soft constraint, ie it tries
to meet this inventory level but will go below the
minimum level if required to meet the demand.
A problem is reported when the inventory drops below
this level.The safety stock target is expressed as a
quantity. If you want to define a safety stock target
as a time value (aka days of inventory), you can set a
post-operation timeon the producing operation of the
buffer.
Default is 0, indicating no safety stock.
|
minimum_calendar |
calendar |
Refers to a calendar storing the desired minimum inventory
level, aka safety stock.
Use this field when the minimum inventory level is varying
over time. Otherwise use the minimum field. If both fields
are specified, the minimum field is ignored.
|
maximum |
double |
Desired maximum inventory, aka order-up-to level.
When the buffer needs to be replenished, the planning algorithm
tries to refill to this level.
Default is 0, indicating replenishments of any quantity are
accepted. Note that operations can still define constraints
on the replenishment size.
|
maximum_calendar |
calendar |
Refers to a calendar storing the maximum inventory level.
Use this field when the maximum inventory level is varying
over time. Otherwise use the maximum field. If both fields
are specified, the maximum field is ignored.
|
tool |
boolean |
A flag to mark buffers that are actually representing a tool.
Default is false.
The impact on the planning results is visible in the
pegging and criticality calculations.
This field is only visible in the planning engine. In the
user interface you use the subcategory field to set this
field to true.
|