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<ManualTopic ID="/baanerp/cp/onlinemanual/000026" xml:lang="en">
	<Header>
		<Title xmlns:ssa="http://www.ssaglobal.com" xmlns:HTML="http://www.w3.org/TR/REC-html40">Net-change simulations</Title>
		<Keyword><Level1>Net-change simulations</Level1>
		</Keyword>
	</Header>
	<GeneralSection><List><ListIntro>A simulation run in <GUIRef href="/baanerp/cp" role="package">Enterprise Planning</GUIRef> can be carried out in two modes:</ListIntro>
			<ListItem>Regenerative</ListItem>
			<ListItem>Net change</ListItem>
		</List>
		<Paragraph>This applies to <Link href="/baanerp/cp/glossary/glossary#000059" role="glossary">master planning</Link> as well as <Link href="/baanerp/cp/glossary/glossary#000060" role="glossary">order planning</Link>.</Paragraph>
		<GeneralSection><SectionTitle>Regenerative simulation</SectionTitle>
			<Paragraph>In a regenerative simulation, the planned supply of each plan item is recomputed, regardless of whether the planning data has changed since the last simulation or not.</Paragraph>
		</GeneralSection>
		<GeneralSection><SectionTitle>Net-change simulation</SectionTitle>
			<Paragraph>In a net-change simulation, the master plan or planned orders are only regenerated for plan items for which the planning data has changed since the previous calculation, and for plan items that are affected by such changes.</Paragraph>
			<Paragraph>For each plan item, SSA ERP records if a change has occurred since the last simulation (for example, a change in the bill of material or changed demand figures). SSA ERP also records the earliest date on which a change has occurred (the <Link href="/baanerp/cp/glossary/glossary#000079" role="glossary">net-change date</Link> ). You can find this data in the <GUIRef href="/baanerp/cp/rpd/cprpd1100m000" role="session">Items - Planning (cprpd1100m000)</GUIRef> session and the <GUIRef href="/baanerp/tc/ibd/tcibd2500m000" role="session">Items - Ordering (tcibd2500m000)</GUIRef> session. This data is used to determine the starting point for the next (net-change) simulation. SSA ERP uses the earliest of the net-change dates in the <GUIRef href="/baanerp/cp/rpd/cprpd1100m000" role="session">Items - Planning (cprpd1100m000)</GUIRef> session and the <GUIRef href="/baanerp/tc/ibd/tcibd2500m000" role="session">Items - Ordering (tcibd2500m000)</GUIRef> session.</Paragraph>
			<Paragraph>During a simulation, the plan item's net-change status is reset.</Paragraph>
		</GeneralSection>
		<Note><SectionTitle>Note</SectionTitle>
			<Paragraph>SSA ERP maintains one net-change date for <Link href="/baanerp/cp/glossary/glossary#000059" role="glossary">master planning</Link> and for <Link href="/baanerp/cp/glossary/glossary#000060" role="glossary">order planning</Link>.</Paragraph>
		</Note>
		<ExampleSection><SectionTitle>Example</SectionTitle>
			<Paragraph>You plan a gearbox with master planning. The master plan is generated for 12 monthly plan periods. Later your company decides that a different type of (critical) gear wheel should be used, and the <Link href="/baanerp/ti/glossary/glossary#000081" role="glossary">bill of critical materials</Link> is adapted accordingly. The change is effective on May 15th. When you carry out a net-change simulation, SSA ERP recalculates the plans for the gearbox for May, and all subsequent plan periods. SSA ERP also recalculates the plans for the gearbox's components for May, and all subsequent plan periods.</Paragraph>
			<Paragraph>When you run a master-plan simulation or order simulation, you can indicate that you want this simulation to be a net-change run by selecting the appropriate check box. (However, this option is not available in the <GUIRef href="/baanerp/cp/rmp/cprmp1203m000" role="session">Generate Master Planning (Item) (cprmp1203m000)</GUIRef> session.)</Paragraph>
		</ExampleSection>
		<Note><SectionTitle>Note</SectionTitle>
			<Paragraph>When a modification is performed at the scenario level (for example, the plan-period definition), a regenerative simulation must be performed.</Paragraph>
		</Note>
		<GeneralSection><SectionTitle>Net change in inventory transactions</SectionTitle>
			<Paragraph>The net-change status in inventory transactions affects both master planning and order planning.</Paragraph>
			<Paragraph>The net-change status and the net-change date for inventory transactions are displayed in the <GUIRef href="/baanerp/tc/ibd/tcibd2500m000" role="session">Items - Ordering (tcibd2500m000)</GUIRef> session.</Paragraph>
		</GeneralSection>
	</GeneralSection>
	<RelatedTopics><SectionTitle>Related topics</SectionTitle>
		<RelTopic><Link href="/baanerp/cp/onlinemanual/000305" role="manual">Supply planning</Link>
		</RelTopic>
		<RelTopic><Link href="/baanerp/cp/onlinemanual/000072" role="manual">Net-change date before time fence</Link>
		</RelTopic>
	</RelatedTopics>
</ManualTopic>
