PLC / HMI, SCADA, Alarms & Historian
Investigate shifted PLC trend timestamps without rewriting history
A chart can display valid stored times in an unexpected timezone or daylight-saving interpretation.
Environment and inputs: Industrial PLC / automation guidance · Verify the exact controller, module, firmware, engineering tool and machine documentation. Linked vendor examples apply to their stated products and library versions; observation, state changes and physical work require distinct authorization.
Observe and record
Compare source, gateway, database and client timezone settings, stored timestamp meaning and the chart's display configuration.
Interpret the evidence
An apparent hour offset can be a display interpretation, while a real clock error affects event order differently. The two require different corrections.
Resolve and verify
Repair the verified time interpretation or synchronization path through the platform owner and validate known reference events before any historical correction.
Machine and data safeguards
Do not bulk-shift production history until timestamp provenance, backup and downstream reporting effects are understood.