Understand work orders and jobs

Production rates are calculated as jobs are executed according to work orders.

To track the progress of job execution, it is helpful to understand work order status and job states.

Work orders

A work order represents a request for some quantity of an item to be produced. A work order is uniquely identified by its ID number. Once completed, a work order is not intended to be executed again.

For line management, work orders can be created and assigned to lines in MES Web Portal. Work orders can also be submitted to MES from an external system, such as a manufacturing resource planning (MRP) or enterprise resource planning (ERP) system, or created in MES Client. The work orders are assigned to specific production lines.

To be executed, the work order must comprise a set of jobs that represent the complete set of operations required to manufacture that product from ingredients or components. These ingredients or components may have been purchased or manufactured as the result of a previous work order. Creating a work order in MES Web Portal and assigning it to a line also creates the necessary jobs for all entities associated with the line. Unlike work orders created using MES Client and worked using MES Operator, there is no correlation to a process and therefore no concept of a bill of material in MES Web Portal. There is the produced item of the work order and the quantities (starting and required).

Work order status

A work order has a status that is determined by the status of its member jobs. Job states are described in Job States.

You can also manually change work order's status. See Change the work order status.

The status of the work order is derived based on the first condition that satisfies the following order:

1. If there is a job running, the work order status is Running.

2. If all the jobs are completed or canceled, the work order status is Complete.

3. If there is any one on-hold job, then the work order status is On Hold.

4. If there is any one suspended job, then the work order status is Suspended.

5. If there is any one ready job, then the work order status is Ready.

6. If none of the above conditions are true, the work status is New.

Jobs

A job represents an instance of an operation for a given work order that is intended to be performed at a given entity. A job can include a list of steps or procedures that are executed to perform that operation. In turn, a work order consists of a set of jobs that are executed to produce an item.

Within the MES database, a job is characterized by a unique combination of work order ID, operation, and internal sequence number.

Jobs are executed on entities. Jobs can be controlled by:

• Starting an existing job on the entity

• Pausing or ending a job that is running on the entity

The recording of job execution data for an entity can be performed by an Operations Capability Object (OCO) instance. In the MES Web Portal, a production operator can manually start a new job or end a job (see Start or end a job).

Job states

• New — The job is scheduled to be run but is not yet ready to start because upstream work needs to be done first, unless the job is for a first operation of a work order. When a new work order is assigned to a line, a job is created for each entity on the line with a status of New.

• Ready — The job is ready to start; all of the requirements for running the job have been met.

• Running — The job is currently running on an entity.

• On Hold — The job has been paused indefinitely, typically because of some problem such as material or machine issues.

• Suspended — The job has been temporarily paused, typically in favor of another more important job.

• Canceled — The job has been permanently stopped before being completed; a record of it is still maintained in the MES database.

• Complete — The job has finished.