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The Big Picture

No single system runs a modern manufacturing operation. It takes an ecosystem of interconnected systems — each handling a different aspect of the business — all sharing data to keep planning, execution, and analysis in sync. Understanding how these systems fit together is what separates people who use software from people who can improve how an operation works.

This is the knowledge that comes from working in complex manufacturing environments like aerospace and defense, where a single product can involve hundreds of thousands of parts, dozens of work centers, and multiple systems all talking to each other.

How to use this interactive: In Explore mode, click any system to see its role, data flows, and connections. In Scenarios mode, walk through real-world events (new order, engineering change, machine breakdown) and see how data flows through every system step by step.

Interactive: Explore the Ecosystem

All Data Flows — Click a System to Filter
PLMERPBOM & ECOs
ERPAPS / SchedulingPlanned Orders
ERPMESWork Orders
APS / SchedulingMESDispatch List
MESERPActuals
MESAPS / SchedulingReal-time Status
MESBIProduction Data
ERPBIBusiness Data
Shop FloorMESMachine Signals
MESShop FloorInstructions
BIPLMFeedback
ERPPLMCost Feedback

The Five Layers of Manufacturing Systems

Manufacturing systems are organized in layers, roughly following the ISA-95 standard. Each layer operates at a different time scale and serves different users:

LayerSystemsTime scaleKey users
EngineeringPLM, CAD/CAM/CAEMonths to yearsDesign engineers, configuration managers
Business PlanningERP, S&OP, demand planningWeeks to monthsPlanners, buyers, finance, management
SchedulingAPS, finite schedulingDays to weeksProduction schedulers, planners
ExecutionMES, SCADA, quality systemsMinutes to hoursOperators, supervisors, quality techs
AnalyticsBI, dashboards, reportingReal-time to monthlyAll levels — adapted to role

Critical Data Flows

The ecosystem only works when data flows correctly between systems. Here are the most critical connections:

Downward flows (plan → execute)

PLM → ERP: Product definitionEngineering BOM, specifications, and change orders flow from PLM to ERP. This is how "what we designed" becomes "what we plan to build."
ERP → APS: Demand & capacityMRP planned orders, routings, and work center capacity data feed into the scheduling engine for finite-capacity optimization.
APS → MES: Schedule & sequenceThe optimized dispatch list tells MES which job runs on which machine in which order — the "marching orders" for the floor.
MES → Shop Floor: InstructionsWork instructions, inspection criteria, and material requirements delivered to the operator at point of use.

Upward flows (actual → plan)

Shop Floor → MES: Machine & operator dataPLC signals, sensor data, scan events, and operator entries captured in real-time by MES.
MES → ERP: Actual production resultsCompletions, labor hours, material consumption, and scrap flow back to ERP for costing and inventory updates.
MES → APS: Real-time statusCurrent machine status, WIP positions, and actual cycle times enable the scheduler to re-plan based on reality.
All systems → BI: Analytics dataEvery system feeds the BI layer, which transforms raw transactions into the dashboards and insights that drive decisions.

Integration Challenges

In reality, getting these systems to talk to each other is one of the hardest problems in manufacturing IT:

Common integration failures
  • PLM BOM doesn't match ERP BOM — different structures, different part numbers
  • ERP lead times are months out of date — scheduling is fiction
  • MES data never flows back to ERP — actuals and plan diverge
  • BI dashboards show stale data — decisions based on last week's numbers
  • "Islands of automation" — each system works alone
Integration best practices
  • Single source of truth per data type (BOM owns PLM, inventory owns ERP)
  • Automated bidirectional interfaces with error handling and monitoring
  • Master data governance — who owns each data element and keeps it current
  • Near-real-time data feeds (not nightly batch jobs) for execution systems
  • Integration middleware (MuleSoft, Boomi, Informatica) for complex landscapes

Where SymplProcess Fits

SymplProcess operates at the execution and analytics layers — providing structured shift-level data capture (like a lightweight MES) and trend analysis (like purpose-built BI) for operations that need daily operational visibility without the complexity and cost of full enterprise system deployments. It complements rather than replaces ERP and MES, and for many mid-size operations, it's the most practical way to bridge the gap between "we have an ERP" and "we actually know what's happening on the floor."

Key Takeaway

Remember This

A production system is an ecosystem, not a single tool. PLM defines the product, ERP plans the production, APS optimizes the schedule, MES executes on the floor, and BI turns it all into intelligence. The magic happens in the connections between them — data flowing down from plan to execution and flowing back up from reality to plan. Understanding this ecosystem is what allows you to see the whole picture and improve the system, not just your corner of it.

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