Technology / Engineering guide
Wind Monitoring Timestamps, Time Zones & Intervals
A timestamp can mark an observation, an averaging interval or the arrival of a message. Those meanings must be distinguished before aligning wind, electrical and load records. A familiar date format does not establish clock accuracy or synchronisation between devices.
Keep the event time separate from the delivery time.
A useful time record identifies the instant or interval represented, its zone interpretation and any known clock changes.
01 / Two clocks
Distinguish observation time from arrival time.
A measurement may be recorded at the device before a communication system receives it.
A measurement may be recorded at the device before a communication system receives it. Network delay changes arrival time without necessarily changing the observation time. If both fields exist, preserve their separate definitions.
Using arrival order as event order can misrepresent delayed or buffered records. No MARSTON buffering or time-synchronisation feature is assumed here. The review concerns the semantics of whichever records the actual equipment provides.
02 / Zone context
Retain the information needed to identify an instant.
A local date and clock time without an offset or zone context may not identify one instant uniquely.
A local date and clock time without an offset or zone context may not identify one instant uniquely. UTC, a numerical offset and a named time zone also have different roles: an offset identifies a relationship at an instant, while a zone can carry changing civil-time rules.
W3C’s time-zone guidance explains these distinctions. Preserve the original timestamp and its interpretation when producing an aligned dataset, rather than replacing it with an undocumented local display value.
03 / Clock changes
Make repeated and skipped local times visible.
Where daylight-saving changes apply, local clock labels can repeat or skip.
Where daylight-saving changes apply, local clock labels can repeat or skip. A repeated label may describe two different instants. This does not justify discarding either record as an automatic duplicate.
Device clock corrections can also create apparent discontinuities. Retain available change history and explain the treatment in the analysis. An apparent gap in local labels should not be declared a data outage until its time basis is understood.
04 / Interval labels
Identify the represented start and end.
An interval timestamp may refer to its beginning, end or another defined point.
An interval timestamp may refer to its beginning, end or another defined point. Aligning two interval-average series requires compatible boundaries and durations, not merely identical printed labels.
Keep averaging duration, sample coverage and timestamp convention together. For example, a value labelled at an interval end should not silently be interpreted as an instantaneous observation at that time. Avoid inferring a logging interval solely from a few visible rows.
05 / Alignment review
Compare time uncertainty with the question being asked.
Slow seasonal comparison and event-order analysis need different timing evidence.
Slow seasonal comparison and event-order analysis need different timing evidence. Retain the available clock basis, known offset checks and timestamp resolution without equating resolution with accuracy.
The measurement guide covers uncertainty in the chain. Here the practical question is whether the series can support the intended alignment; no network clock protocol or synchronisation accuracy is promised.
06 / Export record
Preserve time meaning across file transformations.
A usable export description includes source field meaning, zone or offset, interval convention, clock changes and transformations applied.
A usable export description includes source field meaning, zone or offset, interval convention, clock changes and transformations applied. Retain a traceable original alongside the aligned result so ambiguity can be revisited.
Use the aggregation guide when computing totals or means after alignment. A converted timestamp improves clarity only when its original interpretation is known; it cannot reconstruct unrecorded timing information.
Continue the review with Wind Data Quality Flags & Aggregation Rules.
Continue the review with Wind Energy Counters, Resets & Interval Totals.
Continue the review with Wind Sensor Analogue & Digital Signal Interfaces.
General background: W3C: time-zone, wall-time and timeline distinctions. These references explain industry concepts; they are separate from the applicable MARSTON product and project documents.
Prepare the information for this review.
Use the checklist to organise the project information. Mark unavailable items and retain document references.
| Review item | Information to provide | Purpose |
|---|---|---|
| Timestamp role | Observation, interval label or arrival time | Separate event and transport timing. |
| Zone interpretation | UTC, explicit offset or named-zone context | Identify the represented instant. |
| Interval definition | Start/end convention and duration | Align comparable periods. |
| Clock history | Corrections, civil-time changes and available offset evidence | Explain discontinuities. |
| Export transformation | Original fields and documented conversion | Preserve traceability. |
Engineering questions.
Is message arrival time the same as observation time?
Not necessarily. Communication or buffering can separate them.
Does timestamp resolution prove clock accuracy?
No. Displayed precision and timing accuracy are different properties.
Are repeated local clock labels always duplicate records?
No. Civil-time changes or clock adjustments may give distinct records the same label.
Is a numerical UTC offset a full time-zone rule?
No. It gives the offset for the relevant instant, not every past or future civil-time rule.
Does this guide confirm synchronisation functions in MARSTON equipment?
No. The actual record and supported device functions require documentation.
What should accompany aligned data?
Timestamp meaning, zone interpretation, interval boundaries, clock history and the applied transformation.
Technical enquiry
Bring your project information to the discussion.
A timestamp can mark an observation, an averaging interval or the arrival of a message. Share the available information and the equipment scope you want reviewed in a technical quotation.