When production orders are first created, either manually or through planning, they have realistic, but not necessarily optimal operation starting and ending times – this is called rough scheduling. In this automatic scheduling, the system considers different requirements, such as capacity need, capacity availability, and due dates and then it places (loads) operations in the calendar backwards from the production order due date. The more production orders created for the same (or proximate) due date, the earlier the starting date of the last one created. This logic functions well and provides a solid foundation, but it does not load the production resources optimally and you may therefore want to perform rescheduling – also called fine scheduling.
Rescheduling can be defined as changes you make concerning:
the starting and ending times of individual operations
which production resources operations are performed at.
Prior to rescheduling, you should make any necessary changes to the production order requirements, which influence the capacity need. These include changing components and/or operations, increasing the order quantity, changing the due date, etc.. (See Refreshing/Replanning a Production Order). Another requirement, which you can change and thereby affect the schedule, is the total capacity (time units) available according to the respective work center calendars used (see Creating Work Center Calendars).
You can enter the Production Schedule window from different places causing slightly different behavior:
From a planned, firm planned, or released production order, click Functions, Production Schedule.
The same can be done in the Order Planning window, from a planning line of demand type Production.
The Production Schedule window opens showing all existing production orders (except simulated and finished). The operations for the relevant production order are highlighted with blue color.
Note: The relevant operations may not be visible within the default view when the window opens (see below).
Open the Production Schedule window from the Navigation Pane. (See also Checking Order Progress.)
You can also open it from the Order Planning window, from a planning line of demand type Sales.
The Production Schedule window opens showing all existing production orders.
Locate the operation that you wish to reschedule.
A tooltip text displays all relevant information when you place the cursor over an operation.
Maximize the Production Schedule window by pressing Alt + space + x or click the Maximize button.
Zoom in and out by pressing Shift + keys -/+ or press Shift + right/left mouse button.
Click and drag the time scale right or left to show more or fewer days.
Click the Production Order View/Resource View button to see operations in the context of orders or resources.
Click the expand/collapse icons (+/-) to see the production resources performing the operations.
The system allows you to move operations along the time scale – within the constraints of the production data.
Right-click on the operation and select Show Links from the menu. (This is very useful if there are related operations, see also Step 3)
With the cursor on the operation, click and drag the operation bar horizontally to change its starting/ending times.
Right-click on the operation and select Schedule previous/next operations to reschedule related operations automatically according to the manual move you have made.
Right-click on the operation and select Restore initial values to cancel all changes made to the operation(s) since the Production Schedule window was opened or saved.
The system allows you to move operations to other production resources – within the constraints of the production order data and resource setup. Note: this is only possible in Resource View.
Click Resource View.
Click once on the operation to enable it for a vertical move, (indicated by black dots around the operation).
With the cursor on the operation, click and drag the operation bar vertically to move it to another resource.
During both of the above rescheduling tasks, the system shows different types of messaging:
A tooltip text box is displayed while you drag, showing the changing starting/ending times.
If you drag the operation so far forward in time that it, or a related operation, exceeds the due date (shown as red square), then the operation and all its related operations are shaded with a hatch pattern.
If you drag the operation to a starting/ending time that exceeds those of related operations, the following message is shown: “The operation sequence is violated. Do you want to move the operation anyway?”
In many cases you can click Yes to this message as you are in the process of moving related operations.
If the operation has already started (output is posted), the system will disallow the move and display a message.
If the operation is marked as finished (on the production order routing line), the system will disallow the move and display a message.
If a subcontract purchase order date is violated when moving an operation, the system will show a warning.
If production order data is changed since you last saved or closed the Production Schedule window, a conflict message is shown and those operation changes are indicated in the window with cross-hatch shading.
Once an operation has been moved, it will have a red border (until the window is closed).
The load histograms in the bottom of the Production Schedule window are constantly updated to display the total time allocated to resources by the operations immediately above them. You can not interact in the histogram but you can select which resources to see the load columns for. Note: Values shown in load columns are based on an average time span between starting and ending times.
Click Resource View.
In the Show Load column at the far left of the window, place a check mark by each resource that you want to see a histogram for.
Note: The split bar above the histogram pane may need to be lifted to show all the load histograms selected with the check marks.
You can have the system show progress (operation output) on each operation. In the Production Schedule Setup window, you can select whether this progress value should be based on:
Time – run time and setup time posted
Quantity – output quantity posted (see Registering Consumption and Output)
Right-click anywhere in the interaction pane and select Show Progress from the functions menu.
The system now shows the progress on each operation in the production order as a percentage figure. This figure is defined as the output posted (actual) as a percentage of the total quantity to be outputted (expected).
Note: Component Availability
In the Production Schedule window there are no system checks concerning component availability after rescheduling. The interrelation between Order Planning and Production Schedule is based on an all manual work flow. There is no automation logic between the two. You can say that one is giving new requirements to the other with every action in this work flow. Therefore, you may have to manually check availability after every rescheduling performed. (See Checking Availability against Schedule.)