Follow these guidelines for the scheduling system to work properly and provide good results.
Do not co-opt item order policies for cross-purposes
Do not co-opt item order policies for cross-purposes where you sometimes plan an item to order and sometimes plan it for stock (Demand Driven). The only proper use of item order policies is for each item to always be planned to order or to always be planned to stock (Demand Driven).
Avoid adding extra days to P Item Lead Days or M Item Job Days
The scheduling system works most efficiently when the MRP “action window’ is equal to each item’s replenish time. Avoid adding extra days or padding to your P Item Lead Days or M Item Job Days. Fictional values in your lead days and job days will severely impact your system target dates, material allocations and your inventory stocking levels. If your objective is to enlarge your item's planning period action window during MRP generation, you can go to the MRP Setup - MRP Defaults and add extra days to your MRP replenishment time.
Use default SO Required dates
Use default SO line Required dates, which reflect your item order policies and allocations, without manual intervention. If any required date is not as desired, change the underlying settings so that your planned time to shipment meets your strategic objectives for this order and future orders as well. Never allow the required date to be used as a “wish date” by salespeople because it is a manufacturing date that must be aligned with dependent jobs and POs. You can use the Expected Ship date for customer communications. The Expected Ship date can be freely changed without impacting system dates or allocations.
Do not adjust SO Required dates when supply jobs are trending late
Do not adjust SO line Required dates when supply jobs are trending late. Otherwise, the sales order loses priority within the Sales > Picking Manager.
Use the Expected Ship date as the customer communication date
The Sales > Late Supply screen will help you update the Expected Ship date for items that are running behind schedule.
Generate MRP on a daily basis
The most efficient way to perform just in time planning is to generate MRP on a daily basis. This way you always respond immediately to any new demand that arises. Unlike manual planning, which is time-consuming and therefore is often done only once or twice a week in lengthy sessions, daily MRP generation only takes a few minutes.
Never generate partial or fragmented MRP sessions
Each MRP session is designed for complete generation and conversion through all job levels and always finishing with PO generation and conversion. Complete generation is an absolute requirement for achieving a coordinated master schedule. Never skip levels or generate jobs on one day and POs on another.
NOTE: This guideline does not mean that two people cannot participate in an MRP session. A production planner, for example, could generate the entire session and convert jobs, but could pause the session after PO generation so that a buyer could convert the planned POs after verifying supplier prices and other details.
Never delay planned job or PO conversion
When MRP generates a planned job or PO, it must be converted immediately in order to avoid introducing late dates into the master schedule. Never delay conversion because this defeats the “just in time” nature of the master schedule.
Do not bypass MRP with manual jobs and POs
MRP generates a coordinated master schedule in which all dates are inter-connected and work centers are prioritized based on meeting required dates. When you interject a manually created job or PO into the master schedule, it has no relationship with other dates and disrupts the schedule by misallocating material and distorting work center priorities.
Do not create future jobs
Do not manually create future jobs in anticipation of future demand or to comply with blanket sales orders. This is a crude form of forecasting that is not compatible with just in time planning and the master schedule. The correct way to plan for anticipated demand is to enter a Monthly Forecast and Supply Days target to automatically generate demand-driven jobs at planned intervals.
Do not manually adjust job dates
Job dates are coordinated upon creation with dependent demand dates and are automatically adjusted at time of job release with no need for manual intervention prior to job release.
Only release jobs when material is available
Never release a job without allocated material, which disables the means by which jobs are started in the correct order of assembly and given new finish dates to reflect actual conditions on the ground.
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Essential #3 - Release Jobs with Material
Run work center sequences in job priority order
Whenever possible, run work center sequences in job priority order so that late trending jobs are automatically expedited as needed to meet their required dates.
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Essential #4 - Coordinate Work Centers
Track job labor using Standard Hours completions
Track job labor as sequences are finished, using standard or actual hours, in order to update work center queues and job priorities.
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Essential #6 - Track Job Labor
Use the Late Supply screen to manage customer communications for shipment dates
The Sales > Late Supply screen provides feedback to your office staff to update the SO line Expected Ship date for Jobs or POs that are running behind schedule.
Use the Picking Manager to ensure that you are following your plan
The Sales > Picking Manager screen allocates your stock on hand in priority order to ensure that you are staying on time across all sales orders company wide.
