mediumConceptEntryMidSenior
Walk me through what a PLC, a SCADA system, a historian and an MES each do, and how they relate to ERP.
4 min readUpdated 2026-08-15
Answer
Short answer
A PLC runs the machine on a deterministic scan cycle and holds the truth about plant state; SCADA gives operators a view and supervisory control; a historian archives the resulting time series; an MES turns a production plan into work orders and a batch record; ERP sits above with the commercial view.
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Likely follow-ups
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