In this task you will plan a standard Job Days and Run Size for all M items.
MRP Settings is a super task set!
You must enter:
1.Reasonable Lead Days on 100% of your purchased items
2.Reasonable Job Days on 100% of your manufactured items
3.A clear cut item Order Policy based on lead day contribution
Do not skip or partially complete
Item MRP settings -- along with BOM routings and locations -- is a "super task" set. Item MRP settings are required for MRP and shop control and cannot be skipped or partially completed.
Links:
MRP Guide - Time to Shipment Planning
Video - Guideline M Item Job Days
Plan a standard Job Days for all M items
(MRP - MRP Settings)
In this task you will plan a standard Job Days and Run Size for all M items.
The M item Job Days is a required MRP setting
The manufactured item Job Days is an integral element of Time to Shipment MRP and is a required setting that cannot be skipped or given artificial values. Without exception a standard Job Days must be assigned to each and every M item.
The Job Days is standard production time
The Job Days setting is the item's standard production time for a typical job quantity, expressed in shop days.
Job Days Purposes
Establishes job dates
The Job Days is accompanied by the pre-job Lead Days, which is automatically calculated and is the time allocated for making subassemblies or procuring materials to order before a job can be started. Together the two settings comprise the item’s lead time and establish job start and finish dates.
Contributes to higher-level lead times
A job that uses a component item with a To Order policy must wait until the item is procured or manufactured before the job can be started. When several To Order policy components exist, the one with the longest lead time determines the parent item's pre-job Lead Days allocation. Therefore any lower level M item with a To Order policy is a lead time contributor to higher-level items.
Contributes to Time to Shipment
When a top level sell item has a To Order policy, its pre-job Lead Days and standard Job Days contribute to its Time to Shipment target for sales order required dates. This provides sufficient time for making the item to order.
Enables late job tracking and job rescheduling
The standard Job Days determines job finish dates for late job tracking in the Job Schedule screen and for job rescheduling in the Job Control Panel - Release Jobs screen.
Determines item planning periods
The pre-job Lead Days and standard Job Days (along with the system MRP Interval setting) determine each item's planning period action window for job generation. Any demand beyond the planning period will be responded to in a future MRP session when it falls into the action window and becomes current demand.
Replenishment Time affects inventory levels
Your Job Days value contributes to the Replenishment Time for your items. In the Demand Driven order policy, the system will convert the Monthly Potential Demand value into a daily usage and multiply that by the Replenishment Time for the item to establish the Reorder Point. Therefore, it is essential that your Job Day allocations remain reasonably accurate to keep your inventory lean and efficient.
The Job Days and pre-job Lead Days are not isolated settings
The Job Days and pre-job Lead Days are not isolated settings. When a lower level subassembly item has a To Order policy, its lead time contributes to the lead times of higher-level items. If you give the Job Days a padded or inflated value, you get inflated lead times at higher levels, inflated time to shipment targets, and distorted sales order required dates. So it is essential that the Job Days is a realistic value that approximates actual production time.
A standard Run Size accompanies the Job Days
Each item's standard Job Days is accompanied by a standard Run Size, which represents a typical job quantity.
Run Size Purposes
Used for Job Days Inquiry calculations
The standard Run Size is used to calculate an estimated Job Days amount in the Job Days Inquiry (see below), which can be used as a reference to help establish the standard Job Days value.
Amortizes setup and fixed usage quantity cost
The standard Run Size is used by the cost rollup to amortize total fixed setup cost and fixed quantity component cost into a unit cost.
Job Days Entry
Go to the MRP Setting - M Items screen and enter a value in the Job Days field.
Guidelines
•Enter a realistic value that is standard production time for a typical job quantity, expressed in shop days. Production time is the total number of days between job start and job finish and includes actual processing time, work center queue time, and move time between work centers.
•Many M items have similar or identical production processes, in which case the same standard Job Days can be applied to multiple items.
•An approximate value based on judgment and past experience will provide good results. Standard Job Days values can be refined over time as you get feedback from actual results.
How can a standard Job Days apply to different job quantities?
How can a standard Job Days setting apply when job quantities vary from job to job? The standard Job Days is for time to shipment planning where the ultimate objective is to achieve consistent ship dates over time from order to order. When a job has an unusually large quantity, the job gets higher priority in work center queues, which reduces overall queue time and enables the job to meet its required date. So dates stay fixed for consistent scheduling and shop activities flexibly adapt to meet the schedule.
Never adjust Job Days for particular situations
One thing you must absolutely avoid is adjusting standard Job Days values on a situational basis to accommodate a particular requirement or order quantity. Doing so will disrupt date alignment within the master schedule. Use standard Job Days settings and the system automatically adjusts job priorities to accommodate unusual quantities.
Never pad or inflate Job Days to expand item planning periods
Another thing you must absolutely avoid is to pad or inflate Job Days settings in order to expand item planning periods. Inflated Job Days settings inflate higher-level lead times and time to shipment targets and distort sales order required dates.
If you prefer longer planning periods:
Item planning periods keep inventory lean because they prevent jobs from being generated prematurely before they are needed. That being said, if you feel more comfortable with longer planning periods, never pad or inflate Job Days settings, which has harmful consequences. Instead, go to the MRP - MRP Defaults screen and use the Planning Period - Extra Days for Lower Level M Items setting to expand all subassembly item planning periods by a set number of days.
Planning periods are never expanded for top level items
Planning periods are never expanded for top level items because premature job generation at the top level will generate premature demand for lower items that would cause excessive inventory and introduce long term dates into what should be a firmly set master schedule. The planning period for top level items is also ideally suited for handling blanket sales orders because it excludes demand from future required dates that does not need current action.
Use the Production Inquiry for guidance
For guidance in establishing the standard Job Days, click the Production tab to reference actual shop days for past jobs.
Use the Job Days Inquiry for reference
For assistance in establishing the standard Job Days, click the button in the Job Days field to launch the Job Days Inquiry, which calculates an estimated Job Days based on applying the item’s standard Run Size to current work center capacity settings and routing cycle times.
CAUTION: The calculated Job Days will only have meaningful value if work center capacity settings are properly established.
Shop Control Guide - Setup - Work Center Capacities
Run Size Entry
Enter a standard Run Size that represents a typical job quantity.
Use the Production Inquiry for guidance
For guidance in determining an appropriate Run Size, click the Production tab to reference past job quantities.
