Availability Check – Basics and CustomizationA. Basics1) Backward Scheduling calculates the material availability date. This is the date on whichsufficient material should be available(for activities such as picking,packing,loading and finallygoods issue) so as to be able to successfully deliver the goods to the customer on his requesteddelivery date.(assuming customer requires complete delivery)2) The delivery,therefore,should be created latest by this date or by transportation planingdate,whichever is earlier.3) Availability Check is a function of SAP SD module that along with Transfer of Requirementshelps in checking if sufficient quantity of goods is available on the above calculated availabilitydate.4) If sufficient quantity is not available on this date then goods cannot be delivered on thecustomers requested delivery date.5) Forward Scheduling then calculates the new availability date and thus a new delivery date isconfirmed in the schedule line.6) Availability check is done at Plant Level.7) Results of availability check may vary according to Replenishment Lead Time(RLT) , PartialDelivery Constraints or other such considerations.(described ahead)8) Types of availability check :a) Against ATP Quantities (with or without RLT)b) Against Planning.c)Against Product Allocation9) Available-To-Promise or ATP : On any given date ATP quantities give the number one cancommit for an order which is to be delivered on some future.ATP= Warehouse Stock + Planned Inward Receipts – Planned Outward IssuesWhere Stock can include unrestricted stock,stock in transfer,stock in quality inspection,blockedstock,restricted use stock etcInward Movements can include Purchase Orders,Purchase requisitions,Plannedorders,Production orders etc.Outward Movements can include Sales Orders,Deliveries,Reservations,Sales Requirementsetc.10) R-L-T : The time needed to produce or order the material. In other words it is the time bywhich the material is produced in house or if it is trading good the time by which it can beprocured. If availability check includes RLT , the check is carried out only till the end of thistime any amount will be available after this time.For goods produced in-house :R-L-T = Tot. Replenishment time (MMR-MRP3 View), If maintainedelse if above field not maintainedR-L-T = In-House Production Time (MMR- Work Scheduling view) + GRprocessing time (MMR-MRP2 View)For externally procured goods :R-L-T = Purchasing Processing time(MMR- Purchasing view) + Planned Deliverytime(MMR-MRP2 view) + GR Processing time (MMR-MRP2 view)$$ RLT is included only in check against ATP. * MMR is Material Master record
11) Complete Delivery/Partial Delivery Indicator : Complete delivery indicator is specified inCuMR – Shipping Tab and is applicable at the header level of the Sales Order. This specifies ifthe entire order that is all the items in the order are to be delivered together.The Partial delivery indicator(and the number of partial deliveries allowed) comes fromeither CMIR or CuMR- Shipping Tab. This specifies if all the quantities of the item has to be deliveredin one single delivery or can be delivered in multiple partial deliveries. This is applicable at HeaderLevel but can be changed at item level in the Sales Document.* CMIR – Customer Material Info Record CuMR – Customer Master RecordEffects on Delivery date of complete and partial delivery.% In above figure the End lead time(R-L-T) is 15.05.2013. Any quantity ordered will be confirmed for that date.B. CustomizationSince Availability Check lies within the integration precinct between SD and MM the control featurescan be found in both SD and MM module. The focus here is on customization in SD but a bit of MMfeatures are also studied for getting a holistic picture.I)1) Transfer of Requirements : Requirements are planned outward movements. All material ordersare transferred to the MRP in the form of requirements by SD. This also helps in planningfuture requirements as procurement can further advice production(in case materials need to be
produced) or purchasing(in case materials need to be procured).Without ToR availability checkis not effective.2) Planning Strategies : Are business procedures for planning the production (quantities and dates)of material.3) Strategy Group : The allowed planning strategies (main strategy and further possible strategies)are combined in the strategy group. The strategy group is plant-wise assigned to MRP group.Also strategy group can be directly maintained in MMR-MRP3(which has priority over MRPassignment).4) MRP group : Groups materials having the same MRP requirements and thus helps controllingthese materials for MRP. This is maintained in MMR-MRP1 view.5) MRP Type (MMR-MRP1 View) : Is a key that determines how the material is to be planned.6) Requirements Type : Among other things Requirements types refer to the Requirements class.Requirements Types in turn are a part of Planning Strategy. If not maintained there they aredetermined from the combination of MRP type and Item categories.7) Requirements Class : Apart from other things it controls globally if availability check and ToRis to be done for the material in SD Documents on the basis of ATP Logic.8) Schedule Line Categories : Where Requirements Class determine globally if availability andToR is to be done, at Micro level this is determined by Schedule Line Category. Thus if they areswitch on at Requirements Class level they can be switched off at Schedule Line Level but ifthey are Off at Requirements Class level they cannot be turned on at Schedule Line Level.9) Delivery item category : The delivery item category can be used to control whether anavailability check takes place in deliveries.10) Checking Group : Decides which requirement to transfer - individual(for each order) orsummarized(Daily/Weekly) and whether to block the material(at plant level) during the time ofavailability check for simultaneous orders. Also can deactivate availability check. It is proposedin MMR.11) Checking Rule : Along with Checking Group it decides scope of check for a particulartransaction and id hard coded for example for Sales Order it is A for delivery it is B etc12) Scope of check : Decides what kind of stocks,incoming movements,outgoing movments are tobe checked during availability check and if check includes RLT. It also checks if AvailabilityCheck is to be done on Storage Location Level or not.To summarize (Refer Snapshots below for all relevant transactions):Strategy group contains planning strategies which in turn contain RequirementType(if not there it comes from combination of MRP Type and Item Category) which in turn refers toRequirements class which globally determine, for the material, if Availability check and ToR are to bedone and locally this is controlled by Schedule Line Category in Sales Document and by Delivery ItemCategory in Delivery Document.Checking Group decides if requirements are to be transferred weekly,daily or pertransaction. Also along with checking rule it decides scope of check.
SNAPSHOTS1) T-Code: MM03Strategy group Assignment2) T-Code OPPTStrategy group – Planning Startegies
3) T-Code OPPSPlanning Strategy – Requirement Type4) T-Code OVZHRequirement Type – Requirement Class Assignment
5) T-Code OVZG6) T-Code VA03Requirement type in Sales Order
7) T-Code VOV6ToR and Availability in Schedule Line Category8)Checking Group