About Operation Run Time - Planning and Scheduling
An operation's run time begins after these events:
- Finish time from the previous operation in the routing completes.
- Move time from this operation completes.
- Setup time (adjusted for the operation's Efficiency value) from this operation completes.
The operation may require resources from Labor, Machine, and Other (for example, fixtures) resource groups. If an operation specifies multiple resource groups that are of different types, the operation must specify the Schedule Driver. The Schedule Driver determines whether to use labor hours or machine hours to drive the schedule. If the resource groups are all of the same type, the run hours for all the required resource groups drive the plan and schedule.
To determine how to plan or schedule the operation, the system:
- Divides the hours per-piece value by the number of resources required from the resource group of the Sched Driver type.
- Multiplies the result by (100 / Efficiency) and places the adjusted value in the Run Duration field.
- Applies the Run Duration to all required resources.
If the operation's Use Fixed Schedule option is selected, the system applies the Fixed Sched Hours and does not divide the hours by the number of resources.
Costing considers the run hours for all labor resource groups and adds the fixed machine overhead cost. The hours entered on the job operation are the total hours required for 1 piece.
Planning and Scheduling Example
Suppose an operation specifies the following information:
| Resource Group | Group Type | Qty Resources | Hours Per Piece |
|---|---|---|---|
| WorkersA | Labor | 2 | 1 labor hour |
| Drill | Machine | 1 | 2 mach hours |
| FixtureA | Other | 1 | (2 mach hours) |
- Schedule Driver is Labor.
- Efficiency is 80.0.
- Job quantity is 6.
Given this information, the system performs these steps:
- Divides the labor hours per piece value by the number of labor resources required: 1 hour / 2 resources = 0.5 hours. If the Schedule Driver had been Machine, the calculation would have used the machine resource values: 2 / 1 = 2 hours.
- Multiplies the resulting value by the Efficiency: 0.5 * (100 / 80.0) = 0.625 hours.
- Places the adjusted value in the operation's Run Duration field.
- Multiplies the Run Duration by the job quantity to find the total time requirement: 0.625 * 6 = 3.75 hours.
The system applies 3.75 hours of run time to each of the two labor resources, the machine resource, and the other resource for this operation. When the operation is planned or scheduled, the four resources also undergo any move time, setup time (also adjusted for Efficiency), and finish time.
Costing Example
Using the data from the planning and scheduling example above, suppose the operation's Labor Run Rate is 15.00 and the Fixed Machine Overhead rate is 10.00. The cost of the operation would be calculated as follows:
1 labor hour per piece * 6 pieces * 15.00 * (100 / 80.0) + 10.00 = 122.50
Adding or removing resources/resource groups to or from an operation does not affect the operation's cost.