How PLCs, SCADA, MES, and ERP connect.
A practical view of manufacturing data flow. Use it to identify which connection your plant needs next.
- 01
Equipment
PLCs · machines · test stands
Signals, counts, process values
- 02
SCADA & history
Ignition · operator screens · historian
Context, alarms, trends
- 03
MES & ERP
Production records · work orders
Validated business transactions
Equipment signals gain meaning in SCADA and history. Validated production records move to MES/ERP; approved work instructions can flow back. The connection method depends on your systems.
Illustrative reference architecture. Project scope and software licensing vary.
Equipment connectivity
Start with controllers, instruments, and existing interfaces. Confirm accessible signals, timestamps, connection capacity, and the meaning of each value. A raw tag needs context before it becomes a production record.
SCADA and the historian
Operator screens show current conditions. Alarms direct attention; historical records support trends and reporting. Data quality and freshness need to remain visible when a connection fails.
MES and ERP transactions
Add work-order, product, lot, and operator context where needed. Validate records before posting to the business system, and define acknowledgement, retry, and reconciliation behavior.
Failure handling and ownership
Decide what happens when the network, broker, database, or ERP is unavailable. Agree buffering and recovery behavior, access controls, backups, and acceptance tests. The delivered project should include editable files and operating documentation.
Explore the interactive reference
This illustration describes possible layers, not a required software package or a customer installation. Mobile users can also open the diagram in a full window.