1. In order to schedule work order and production schedules, the system first looks in program RTMM, Routing Master Maintenance.
2. The setup time entered for each operation in program RTMM, Routing Master Maintenance, is independent of all other entered hours and parameters. The setup time is the straight number of hours that it takes to prepare for the operation.
3. The indirect, direct (referred to as Hours Per Unit), inspection, machine, and other hours are also used to schedule the operation.
* Standard Calendar Hours for a job are calculated as follows:
(Indirect hours + direct hours + inspection hours + machine hours + other hours)* qty ordered
crew size
4. The operation scheduling runtime also depends upon the operation type.
* Batch operation type runtime is calculated as the machine hours, regardless of the hours entered for direct, indirect, inspection, and other. The remaining hours are used only for costing purposes.
* Unattended operation type runtime is calculated as (quantity ordered * machine hours) / units per cycle. Machine hours entered for this operation type should be entered as machine hours per cycle. All remaining entered hours are used for costing purposes only.
* Regular, Outside Processes, and Indirect operation type runtimes are calculated as follows:
* The system calculates the standard calendar hours and the machine time and uses the greater of the two.
1. Standard calendar hours are calculated as :[(Direct hours + Indirect hours + Inspection hours + other hours) * qty ordered] / crew size
2. Machine time is calculated as (Machine hours * qty ordered ) / units per cycle
5. Standard calendar hours are calculated as Setup + Runtime
6. Move Time is the average days or and fractions of days that it takes to move to the next operation. It is added to the calendar hours.
7. From program WCMM, Work Center Master Maintenance, the Queue Time is added to the beginning of the job. It is the average time that a job waits at the work center before being started.
8. The efficiency and utilization entered for the work center in program WCMM, Work Center Master Maintenance, are also taken into consideration.
* The efficiency measures how well you meet the standard for a job. For example, if the standard for the job is one hour and the work center will finish the job in fifty four minutes, the work center has 110% efficiency.
* The utilization is the number of useful hours that you get out of a day for the work center.
* The efficiency and utilization are expressed as a percentage and multiplied together to determine availability in a net percentage. The net percentage which is multiplied by the runtime, but not setup time.
* Utilization and efficiency affect all other hours regardless of operation type, but move time and queue time are not affected.
9. When a work order is created, the scheduling is determined as follows:
* Due date of the work order - number of days of lead time in program ICPM, Inventory Planning Data Maintenance = start date.
* In the work center for each operation, look at the start time and number of operations available.
* Load the first operation into its work center at the start time for the work center. Continue until all operations are loaded.
* Check the system control records in program SPMM, System Parameters/Default Maintenance, for the operation scheduling setting. If the setting is forward, the load is complete. If the setting is backward, the difference in work days is determined between the finish date and the due date. The start date and time are adjusted for each operation by the number of days between the finish date and the due date.
10. If you have network routings set up, then when the calendar time is determined, the system will check the network routing for the longest path through the operations. Any operations that are not included in this path are scheduled to begin as early as possible. For example, if operation 3 is dependent on both operation 1 and operation 2 being completed, operations 1 and two are started simultaneously.