Prestige Scheduler Version 5 On-Line Documentation (preliminary)

Job Browser

Introduction

To display the job browser, from the EPB you choose Job Browser from the MaintenanceMenu. The [F10] function key is the shortcut for this option. You can also press the Job Browser button on the EPB Toolbar.

The Job Browser is one of the three main forms within PSv5 that you will work with on a regular basis. It has been designed to synchronize with the EPB. For this reason, we recommend that power users of PSv5 (busy active users and in particular designers) have either two display monitors or at least a large wide-screen monitor with higher resolution, so they will be able to have both the EPB and the Job Browser on display side by side. This makes a powerful combination, with the Job Browser becoming your "dashboard" as you navigate jobs on the EPB.

The Job Browser is also where you add update and delete job information:


When data tabs are on display, any data that can be edited is shown in a white control box. Data that is not editable (also termed read-only) is shown in a greyed box. Unless you are an active user, you will not be able to edit any of the fields and they will all be greyed. If you are an active user, some data will be editable only from within the Design Environment.

Editable numeric data has a down arrow at the right of its display box. You can use this to open a calculator tool.

Date boxes also have a down arrow to their right. These can be used to open a calendar tool.

Time boxes also have spin up-down arrows to their right. These can be used to increment or decrement each component of the time being edited.


ToolBar

The Job Browser form contains a toolbar with the common database operations you will perform represented by convenient tool buttons:

These buttons are only enabled when your position, selection or action within the browser makes them relevant.

Whenever you make a change to an editable item in any of the display tabs, the "Save" and "Abandon" buttons become enabled on the toolbar. Until you press the "Save" button ( or ALT-S), no changes are made to the database. Once "Save" is actioned, the changes you have made are commited to the database, including the creation of a new record if you are in "Add New" mode.


Tree View

The tree view presents a heirarchical view of your currently active jobs. Whenever PSv5 needs to re-create the job list, it creates only the job's header nodes. This is to save time. You can navigate the displayed nodes with your up or down arrow to move up or down the tree. Whenever a node is selected, its detail tab becomes visible in the detail panel (the area to the right of the Tree View). To expand a job header node, press your right arrow when you have the job node selected. This is when PSv5 fills the job node with its sub nodes (the job's parts, processes and milestones) and then expands the job node to display these sub-nodes. You can collapse the job's node by selecting it and pressing your left-arrow.

Note that late jobs can be immediately identified in the treeview. The text in the node for the late job is rendered in bold.


Working with Jobs

Although you can import new jobs from the EPB's File Menu, you can also add new jobs entirely from scratch. In either case, such jobs start out in the Scheduler's Bin (also often called the In-Tray).

The Tree View contains only two permanent branches (or nodes) at the root level - one for "board jobs" and the other for "bin jobs". As the name suggests, jobs nested under the board jobs node are jobs that are already scheduled on the planning board. Jobs under the Bin node are jobs that are not yet scheduled.

The "Bin" is an important intermediate step that jobs take on their way to the board. When jobs are imported from an external Information System, it is important that the planner get the opportunity to review information imported before the job gets scheduled. Routings may need to be changed, loadings fine-tuned and so on. Additional information may also need to be added, which is not known to the MIS - a lead time for example.

Job data is arranged heirarchically. One or more parts are attached to a job; one or more processes are attached to a part; zero or more milestones (status or material) are attached to a process.


Adding a new job from scratch

To add a new job from scratch, right click on the bin node. This brings up the context menu, from which you select Add a new job:

Alternatively you can select the bin node with your left mouse then press the [Add New] toolbar button.


The Job Detail Tab is displayed in the display panel. You must give the new job a unique job number. If you endeavour to add a job with the same number as another job in Prestige Scheduler's database you will create an error and the new job will not be added.

A new part for a job can only be added while the job is in the bin and the job's node is selected. Right click on the job's node and choose "Add new part" from the context menu. Alternatively, select the job node with the left mouse button and then press the [Add New] toolbar button. The next-available part number is supplied. This cannot be changed manually. Enter any additional information and then press [Save] to commit the new part.

Normally, you can add a process to a part either from the bin or the board area. However, a job cannot be successfully added to the board if it does not contain at least one valid process. So, for a new job, you will need to add the first process while the job is in the bin.

To add a new process, either right click the part node and choose "Add a new board process" from the context menu; or select the part node and press the [Add New] toolbar button. Here's a board process's detail tab:


Points to note about adding a new board process:

  • The routing order, which gets its initial value from the default for the selected resource must be greater than zero.

  • The net load, which is the sum of (Undone Makeready + Undone Run + Undone Wash) must be greater than 0.

  • The minimum start quantity must be less than or equal to the estimated input quantity.

  • The lead time must be greater than or equal zero.

  • Any external constraints (covered later) must be added after the process itself has been saved.

  • The status of the process cannot be set while it is being added and in fact means nothing until the job has been raised to the board.

  • Any user-defined fields (up to 5) that have been set for the plist table will be available for entry in the process tab.

As many processes as required can be added to a part. As many parts as required can be added to a job.

A new milestone can be added to a process while the job is in the bin or on the board.


Job Details Tab

Whenever you select a job node in the treeview, the job's details are displayed in the Job Tab.

Points to note regarding the job details:

  • Job numbers are alpha numeric, can be up-to 10 characters in length and must be unique.

  • Job numbers for existing jobs cannot be changed.

  • Jobs can be set to backward-scheduled by setting the nominated checkbox. This can be toggled even when the job is already on the board.

  • All fields except the job number, date required and Order quantity can be considered optional fields.

  • Any user-defined fields set at the job level will be visible in this Tab.

  • The leeway represents the time difference between the "Date Required" and the date that PSv5 has estimated that the production for the job will be completed. A red leeway indicates that the job is running late by the leeway amount.


Part Details Tab

Whenever a part node is selected in the treeview, the part's details are displayed in the part Tab. The part's Job Tab is also available for selection.

Points to note regarding the part details:

  • Part numbers are allocated sequentially as parts are added and cannot be changed for an existing part record.

  • All fields except the part number are optional.

  • Any user-defined fields set at the part-level are visible in this Tab.


Process Details Tab

Whenever a process node is selected in the treeview, the process's details are displayed in the process Tab. The process's part and job tabs are also made available for selection.

The process tab is an important frame of reference and is used to accomplish several tasks.

Here are the main points to note:

  • A process must reference a valid board resource, which are contained in the drop-down list.

  • For an existing process already on the Board, only resources that are in the same assignment group will be available for selection from the Resource DropDown List.

  • When a process is first added, the routing order is derived from the resource's nominated default. The routing order can be changed for any process but only from within the design environment.

  • The "Pass" is normally used to distinguish the order of multiple process steps assigned to a common resource and part.

  • “Done” values can be edited either in design or active mode by a user with “Active” rights

  • Estimated and Undone values can only be edited by a designer in design mode.

  • The MRSequence entry is not completely supported in v5.0. This field is used only for display in v5.0, including as the selected value to display above a process bar on the EPB. In v5.1 (due second quarter of 2007), this field will form the basis for dynamic recalculation of make ready times within groups based on the comparisons between MRSequence values of contiguous proceses within the group.

  • Any user-defined fields set at the process level are visible in this tab.


Minimum Quantity

A minimum input quantity is used by Prestige Scheduler to determine the earliest time that the process can start behind its predecessor. Prestige Scheduler will calculate how long it should take for the predecessor to make the minimum quantity and will set this as the minimum time to wait before this process can start. For long runs, this may result in considerable overlap between the process and the predecessor. However, another factor will also be used to determine overlap.

Each board resource defined in PS is given a minimum lag. This value (often set to say 1 hour) determines two things: the absolute MINIMUM delay between the start of production (excluding any make ready) of a process on the resource and the start of a subsequent (successor) process's production (excluding make ready); and the MINIMUM delay between the finish of the production run on the resource and the finish of the production run on the successor.

Hence the minimum quantity will not always prevail in determining overlap. This is most obvious in cases where the successor process step will take less time than the successor (the successor resource consumes faster). PS delays the start of the successor so that the process, once started, should not run out of input from the predecessor.

NOTE:

If the minimum quantity is left at zero, the minimum lag alone will determine the overlapping.


Lead Time

The lead time, if set to a positive non-zero value will determine the number of hours that PS must delay the start of consumption of product coming from the predecessor. It is important to note that the lead time applies to consumption. Hence, any wash-up on the predecessor and any make-ready time on this process are ignored.

Lead time is often use to allow for dry-time. It can also be effectively used on an outsourced-process. In this case, the outsourced process (normally on an infinite row) is given a nominal run time and the lead time is set based on the turn-around time typical for the company undertaking the operation.


Tandem Processes

PSv5 supports the creation of tandems. This is defined as two or more processes that must start (and normally finish) at the same time. This option is useful where a plant has resources that can be used both in-line and independently. In order to form a tandem set, you must first ensure that the processes involved are contained within the same part and have the same routing order. To determine the natural order of the in-line operations, set the “Pass” value to define the sequencing of the in-line resources (1 to x where x is the number of processes making up the tandem group).

The first process in the tandem group needs to be nominated as the “kingpin” for the group. For tandems that must start AND finish at the same time, the kingpin's loading determines the loading for the entire group; the loadings of processes other than the kingpin member being ignored.

The remaining members of the tandem group must be nominated as “bracketed with prior kingpin”.

Prestige Scheduler will ensure that the tandem set is placed on the board so that all members of the tandem group are able to start (and optionally finish) at the same time.

NOTE: It is illegal to add processes to a tandem group if they occupy the same row on the EPB. This makes it impossible to allow them to run together. The EPB calculation engine will declare an error whenever the board is calculated.


Status

The status of a process is only relevant for processes already scheduled on the board. It is a real-world value. Hence, although it is able to be changed for a scheduled process from within the design environment, this is only as a convenience to the planning person. Changing the status of a process from within design mode simply sends the appropriate transaction to Prestige Scheduler's Task Manager. This will not always work:

If the job has only just been raised to the board in the current design session, and you have not yet “published” your new plan, the job will not yet appear as scheduled on your live board. The Task Manager looks after the live board; it knows nothing about your off-line designs. Hence, attempting to change the status of a newly raised process will fail. Make sure you have adopted your design before updating the statuses of any newly raised processes.


Locating existing Jobs

There are three ways to locate an existing job:

If you have the board node and/or the bin node expanded, you can just start typing in the job number provided the tree-view has been selected (by selecting a visible node). The job for the number you typed will become the selected job node provided that the number you typed was valid and the job-node was in an expanded tree. You need to type the job number reasonably fluently – any great delay will clear the buffer; in which case the tree-view will start searching as though your next entry were the first.

When you select either the root bin node or the root board node, a special tab appears in the Tab screen. You can type in the number of the job you are looking for and press the [search] button. This search is not restricted to just active jobs (on the board or currently in the bin). This search will find a nominated job even if it has been completed. If the job has been completed, a third root node will be made available and the completed job will be placed under it.

You can select [Locate Job] from the toolbar. This will bring up a new form containing a composite list of jobs. You can sort this list on any column. You can nominate a filter (will be improved in 5.1). Once you have located the job you require, either press the [Select] button or double-click the row containing the job. This will return you to the job browser with the found job duly selected.


External Constraints

PS provides automatic constraint rules for successor processes within a job-part. A successor is defined as a process that is constrained by its predecessor(s); a predecessor being a process within the part with the next lower routing order. A successor may have more than one predecessor. This occurs if there are more than one process running concurrently (have the same routing order) immediately prior to the successor.

However, as a general rule, processes are not constrained by other processes attached to a different part. If a process from one part needs to be constrained by a process from a different part, this association (called an external constraint) needs to be explicitly established.

The concept of establishing external constraints is normally associated with the tasks of “gathering” and “splitting”. In PS, parts may be split into two or more separate parts; or two or more parts may be gathered together, optionally forming yet another part.

There are some rules you need to follow to establish an external constraint:

  • If the constraint is being established within a single job, the process being constrained must be in a part number that is higher than the part containing the process that will do the constraining.

  • A constraining process can be from a completely separate job. In this case, for the constraint to be recognised when the board racalculates, the job containing the constraining process must have a better priority than the job whose process is being constrained.

To establish a constraint:

  • Make sure that the node(s) of the part or parts containing the constraining process(es) are expanded.

  • select the node of the process that is to be constrained. You will see the “External Constraints” grid in the process's detail panel.

  • Click and hold the node of a constraining process and drag it to within the External Constraints grid.

  • Drop the node into the grid. This will add the node details to the grid.

  • Repeat the drag and drop operation for any other constraining processes.

  • Press [Save] to make the constraints permanent.

To remove an external constraint, select the row in the grid that defines the constraint you want to remove, right click to bring up the context menu and choose [Remove Constraint].