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<ManualTopic ID="/baanerp/cp/onlinemanual/000335" xml:lang="en">
   <Header>
      <Title>Purchase lead time calculation</Title>
      <Keyword type="header" order="d1e199793">
         <Level1>Purchase lead time</Level1>
      </Keyword>
      <Keyword type="header" order="d1e199796">
         <Level1>Lead times</Level1>
      </Keyword>
      <Keyword type="header" order="d1e199799">
         <Level1>Calculating lead times</Level1>
      </Keyword>
   </Header>
   <GeneralSection>
      <Paragraph>An important task of
      Enterprise Planning is to calculate and plan order start dates and
      order finish dates. One of the dates Enterprise Planning calculates
      is the lead time for purchased items.</Paragraph>
      <Paragraph>Dependent on the
      situation, Enterprise Planning uses one of the following three
      methods to calculate lead times for <Link href="/baanerp/cp/glossary/glossary#000048" role="glossary">planned purchase orders</Link>:</Paragraph>
      <List>
         <ListItem>Based on order-specific purchase data.</ListItem>
         <ListItem>Based on the calculated lead time.</ListItem>
         <ListItem>Based on the <Link href="/baanerp/td/glossary/glossary#000011" role="glossary">supply time</Link>.</ListItem>
      </List>
      <Paragraph>The method that LN uses is determined by the supplier that LN selects to deliver the ordered
      goods. LN selects the supplier according to the <Link href="/baanerp/cp/glossary/glossary#000107" role="glossary">priority rule</Link> that you defined in the <GUIRef href="/baanerp/cp/rpd/cprpd7120m000" role="session">Supply Strategy (cprpd7120m000)</GUIRef> session, and is also based on the <Link href="/baanerp/td/glossary/glossary#000097" role="glossary">priorities</Link> that you specified for the eligible supplier
		in the <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef> session.</Paragraph>
      <Paragraph>The <GUIRef href="/baanerp/td/ipu/tdipu0110m000#tdipu010.oltf" role="manual">Lead Time Horizon (Days)</GUIRef> field in the <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef> session determines the method that LN chooses to compute lead time for planned purchase orders. The function
      of the lead time horizon is comparable to that of the <Link href="/baanerp/cp/glossary/glossary#000058" role="glossary">fixed lead-time horizon</Link> that you can set for <Link href="/baanerp/cp/glossary/glossary#000047" role="glossary">planned production orders</Link>.</Paragraph>
      <GeneralSection>
         <SectionTitle>Purchase lead-time calculation based on order-specific
      purchase data</SectionTitle>
         <List>
            <ListIntro>If the finish date is within the lead-time horizon, and LN finds a valid supplier, LN first calculates the interim finish date,
        which is included in the purchase order sent to the selected supplier. The
        lead-time components that LN uses to calculate this date, and the sessions
        from which it retrieves these data are:</ListIntro>
            <ListItem> 
               <GUIRef href="/baanerp/cp/rpd/cprpd1100m000" role="session">Items - Planning (cprpd1100m000)</GUIRef>.</ListItem>
            <ListItem> 
               <GUIRef href="/baanerp/tc/ibd/tcibd2500m000" role="session">Items - Ordering (tcibd2500m000)</GUIRef>.</ListItem>
            <ListItem> 
               <GUIRef href="/baanerp/wh/wmd/whwmd2510m000" role="session">Warehouse - Item (whwmd2510m000)</GUIRef>.</ListItem>
         </List>
         <List>
            <ListIntro>Next, LN calculates the final finish date, for which it
        uses the following data:</ListIntro>
            <ListItem> 
               <GUIRef href="/baanerp/wh/wmd/whwmd2510m000" role="session">Warehouse - Item (whwmd2510m000)</GUIRef>.</ListItem>
            <ListItem> 
               <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef>.</ListItem>
         </List>
         <List>
            <ListIntro>Finally, LN computes the exact order start date based
			 on supplier-specific data. The specific lead-time components that LN uses
			 and the sessions in which they are defined are:</ListIntro>
            <ListItem>Transport time: LN calculates the transport time based on the distance between the <Link href="/baanerp/tc/glossary/glossary#ShipfrBusine_tc" role="glossary">ship-from business partner</Link> address, and
        the address of the receiving warehouse business partners, distance tables, and <Link href="/baanerp/tc/glossary/glossary#Carrier_tc" role="glossary">carrier</Link>.</ListItem>
            <ListItem>Business partner
			 supply time: <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef>.</ListItem>
            <ListItem>
               <Link href="/baanerp/td/glossary/glossary#000040" role="glossary">Internal processing time</Link>: <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef>.</ListItem>
         </List>
      </GeneralSection>
      <GeneralSection>
         <SectionTitle>Purchase lead-time calculation based on calculated lead
        time</SectionTitle>
         <List>
            <ListIntro>If the finish date of the <Link href="/baanerp/cp/glossary/glossary#000048" role="glossary">planned purchase order</Link> is outside the supplier's lead
          time horizon, LN computes the order start date based on the calculated lead
          time, which is the rough purchase item lead time. LN offsets the calculated
          lead time from the finish date to find the start date. The calculated lead time
          is the sum of the following lead-time components:</ListIntro>
            <ListItem>Internal
			 processing time ( <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef>.</ListItem>
            <ListItem>Business partner
			 supply time ( <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef>).</ListItem>
            <ListItem>Transport time (based
          on the distance between the <Link href="/baanerp/tc/glossary/glossary#ShipfrBusine_tc" role="glossary">ship-from business partner</Link> address, and
          the address of the receiving warehouse business partners, distance table and <Link href="/baanerp/tc/glossary/glossary#Carrier_tc" role="glossary">carrier</Link>.</ListItem>
            <ListItem>Business partner
			 safety time ( <GUIRef href="/baanerp/td/ipu/tdipu0110m000" role="session">Items - Purchase Business Partner (tdipu0110m000)</GUIRef>).</ListItem>
            <ListItem> 
               <Link href="/baanerp/wh/glossary/glossary#000395" role="glossary">Inbound lead time</Link> ( <GUIRef href="/baanerp/wh/wmd/whwmd2510m000" role="session">Warehouse - Item (whwmd2510m000)</GUIRef>).</ListItem>
         </List>
         <Paragraph>Next, LN computes
        the finish date by offsetting the business partner safety time and the inbound
        lead time from the requirement date. This is necessary because these two
        lead-time components must be excluded from the supplier's <Link href="/baanerp/wh/glossary/glossary#000409" role="glossary">planned receipt date</Link>.</Paragraph>
      </GeneralSection>
      <GeneralSection>
         <SectionTitle>Purchase lead-time calculation based on supply
        time</SectionTitle>
         <Paragraph>If LN cannot find
        a valid supplier for the purchase order, or if the supplier that LN selects
        has no capacity left, it plans the order without a supplier. In this situation,
        the only purchase-related lead time component LN uses is the <Link href="/baanerp/td/glossary/glossary#000011" role="glossary">supply time</Link> that you defined in the <GUIRef href="/baanerp/td/ipu/tdipu0101m000" role="session">Items - Purchase (tdipu0101m000)</GUIRef> session. This is a substitute for the more specific
        lead-time components such as <Link href="/baanerp/td/glossary/glossary#000040" role="glossary">internal processing time</Link>, business partner supply time,
        transport time, and business partner safety time which LN uses if it cannot
        find a valid supplier for the purchase order.</Paragraph>
      </GeneralSection>
   </GeneralSection>
   <RelatedTopics>
      <SectionTitle>Related topics</SectionTitle>
      <RelTopic>
         <Link href="/baanerp/cp/onlinemanual/000317" role="manual">Cumulative order lead times and horizons</Link>
      </RelTopic>
      <RelTopic>
         <Link href="/baanerp/cp/onlinemanual/000161" role="manual">To compute supply lead-times</Link>
      </RelTopic>
      <RelTopic>
         <Link href="/baanerp/cp/onlinemanual/000316" role="manual">Lead times and horizons</Link>
      </RelTopic>
   </RelatedTopics>
</ManualTopic>