MxAPS uses item setup, material availability, and the schedule start date to decide whether an operation can be scheduled.

Key Concepts

Material Availability

MxAPS considers material availability when an item is configured as a scheduling constraint.

Material availability may include:

1. Current inventory.
2. Expected receipts.
3. Output from other production orders included in the schedule run.

If related production orders share material or produce components for each other, schedule them together so MxAPS can consider the full material picture.

Constraint Tracking

On the Item Card, review the MxAPS scheduling fields.

The Constraint Tracking field controls how MxAPS treats the item:

Use Constrained for items that must be available before an operation can be scheduled.

Use Tracked when shortages should be visible but should not stop scheduling.

Use Ignored when the item should not affect the schedule.

Fence Type

The Fence Type controls which lead time value MxAPS uses when checking constrained material.

MxAPS can use either:

1. The Global Lead Time entered when generating the schedule.
2. The item-specific lead time from the item setup.

MxAPS does not add these values together. It uses the value selected by the item’s fence type.

Global Lead Time

The Global Lead Time field is entered on the MxAPS Generate a Schedule page.

Use Global Lead Time when you want a common material availability fence for items configured to use the global fence type.

Example:

If the schedule starts on Monday and Global Lead Time is set to 2D, constrained items using the global fence must not fall below zero before Wednesday.

Item Lead Time

Items configured to use their own lead time use the item-specific lead time instead of the Global Lead Time.

Use item lead time when different materials require different availability windows.

Example:

A purchased component with a 10-day lead time may need a longer fence than a stocked component that is normally available in 1 day.

Minimum and Maximum Levels

MxAPS item setup also includes minimum and maximum level fields.

Use these fields when the schedule should respect inventory limits beyond simply preventing negative inventory.

Typical uses:

1. Keep safety stock available.
2. Prevent scheduling below a required minimum level.
3. Avoid scheduling replenishment above a maximum level.

Reserve

The Reserve field controls whether MxAPS should reserve the item from now until the start of the operation that requires it.

This is typically set to Never unless the implementation specifically requires reservation behavior.

Best Practices

1. Use Constrained only for materials that should stop or delay scheduling.
2. Use Tracked for materials where shortage visibility is useful but scheduling should continue.
3. Use Ignored for non-critical components.
4. Use Global Lead Time for simple, consistent material checking.
5. Use item-specific lead time when materials have significantly different availability windows.
6. Schedule related parent and subassembly production orders together.
7. Run Business Central planning first when production orders and supply suggestions need to be created before scheduling.

Troubleshooting

If an operation is not scheduled when expected, check:

1. The item’s Constraint Tracking value.
2. The item’s Fence Type.
3. The Global Lead Time used for the schedule run.
4. The item lead time.
5. Current inventory.
6. Incoming purchase orders or transfer orders.
7. Related production orders.
8. Whether related orders were included in the same schedule run.
9. Minimum level, maximum level, and reserve settings.