About Premises

The production demand represents the quantity to be manufactured for each item and configuration.

It is possible to create a production demand comprising one or more items, or one or more configurations of one or more items.

A production demand can be defined in the following modes:

• Quantity mode: Specify how many items you want to produce.
• Detailed mode: Specify how many configurations of various items you want to produce.
• Sequenced mode: Specify how many configurations of various items you want to produce and in which order.

Here is an example of the Production Demand Definition panel for managing production demands on a selected system. In this example, the production demand is defined in Detailed mode and comprises one item that has two configurations.

Production Demand Authoring commands

Add New Production Demand adds a production demand to the selected system.

Delete Production Demand deletes the production demand. The production demand is no longer associated with the system.

Edit Production Demand Names lets you rename the production demand.

Time Unit

Lets you specify the time period for the production demand.

Production Demand modes

Quantity lets you specify how many items you want to produce.

Detailed lets you specify how many configurations of various items you want to produce.

Sequenced lets you specify how many configurations of various items you want to produce and in which order.

Add Item to Production Demand button.

Lets you select an item for the production demand. If you want to associate several items to the production demand, must use this command each time you need to select an item.

The 'x' command lets you remove an item.

Configuration commands

You can add configurations in Detailed and Sequenced modes.

In Detailed mode, Add Configuration lets you add more than one configuration for an item.

You can specify a quantity for each configuration.

The 'x' command lets you remove a configuration.

Sequence command

In Sequenced mode, the Repeat Selected Item Sequence lets you create a sequence of selected items in the production demand.

The purpose of the shift model is to store information of its shift schedule. The shift model allows calculating an aperture time of the system. This aperture time can be linked to a production demand to compute the required cycle time of the system.

Here is an example of the dialog box for managing shift models on a selected system.

Shift model list.

This list contains all the shift models associated with a system. If no shift model has been associated with the selected system, the list is empty.

For a selected shift model, you can modify its name and the duration of its schedule.

Authoring commands

New command to create a shift model.

Removeto remove the shift model from the list. The shift model is no longer associated with the system.

List view of shifts associated with shift model

Shifts are displayed in a list. By default, at least one shift is associated with a shift model. All the fields of the list can be edited. The columns in this list are:

• Duration: the duration of a shift.
• Occurrence: the number of times a shift is sequenced in the shift model duration.
• Allowance: this parameter is a production indicator that helps to specify how the shift effectively works. For example, employees' breaks can be taken into account here, as opposed to just the run times of the machinery.

Add Shift and Remove Shift.

The Add Shift and Remove Shift command allow adding and deleting a shift in the list.

It is impossible to delete all shifts associated with a shift model. The remove command is disabled when only shift remains in the list.

You can use the Premises Usage command to manage planning premises, if there is at least one production demand and one shift model defined on the system.

When Premise Usage criteria is applied, a ratio is computed for each operation in the system. The ratio is the sum of all the quantities for which each operation is valid, divided by the total quantity. This computes the weighted time of the operation.

For the Quantity mode, a configuration is not used when defining the production demand. The only way to know if an operation is valid for a given item is to analyze the implement links. If the operation does not have an implement link, then the product flow is used to retrieve its previous operations and so implement links of these operations can be analyzed.

For Detailed and Sequenced modes, an operation is valid for a given "item-effectivity" couple in the following cases:

• The operation does not implement an item and does not have an effectivity: in this case, the ratio is 1.0.
• The operation does not implement an item and has an effectivity that matches the expected effectivity.
• The operation implements an item in the hierarchy of the expected root item and does not have an effectivity.
• The operation implements an item in the hierarchy of the expected root item and has an effectivity that matches the expected effectivity.

A cycle time is computed from the production demand and shift model criteria.

Duration * Occurrence * Allowance

3(8hr * 5 * 0.8) = 96hr

96hr/168hr = 0.5714

(Production Demand Time Unit/Total Quantity)* Working Time Ratio
= (2628000sec/4000)* 0.5714
= 375.42sec

When a parent operation contains parallel operations with different configurations, Variants Management computes the duration of the parent operation so that the duration equals the sum of the child operations.

To activate Variants Management, right-click the parent operation, select Properties, and in the Reference tab select True next to Variants Management.

The computed duration appears in Workload Balancing and in the Gantt Chart, and is automatically exported to an XML file.