Wind Turbine Vibration Evaluation Evidence Worksheet

Organize measurement, scope and source evidence for an external review against ISO 20816-21:2025. This worksheet checks documentation completeness only; it does not generate a vibration zone, diagnosis, alarm or operating instruction.

ISO 20816-21:2025 · Edition 1Published · May 2025Rated output > 200 kWNo automatic zone

Not a machine-safety decision. A component name and one vibration value cannot establish an ISO zone or justify continued operation, curtailment or shutdown. Use the licensed standard, the correct turbine group and measurement procedure, site/manufacturer limits, and a qualified reviewer.

What the public record establishes

Two drivetrain groups. Group 1 uses a gearbox; Group 2 is direct drive. The public contents also separate their generator evaluation sections.

Scope threshold. The stated rated generator output scope is exceeding 200 kW, not every item labelled “<1 MW”.

Assessment quantities are contextual. Public definitions describe broad-band RMS acceleration or velocity in a given frequency band measured over a fixed period.

Measurement procedure matters. Public contents separately list position, equipment, mounting, quantity formation and operating conditions.

Early fault detection is different. The official abstract says the general zones are usually unsuitable for early fault detection and directs condition monitoring elsewhere.

Manufacturer acceptance is different. Gearbox and generator acceptance measurements at the manufacturer’s facility are outside the stated scope.

Standard and source register

ID	Source and lifecycle	Verified public support	Not supported publicly
S1	ISO 20816-21:2025 Edition 1 · Published 2025-05 · current	Two groups; >200 kW; continuous-load zones; Annex A data scope; diagnostic and acceptance exclusions.	Closed measurement details, numeric zones and operational-limit procedure.
S2	Official OBP preview	Public contents and definitions for assessment acceleration/velocity.	Protected sections 4–6, including exact measurement and evaluation criteria.
S3	ISO 10816-21:2015 Withdrawn · replaced by ISO 20816-21:2025	Previous geared-turbine scope and official lifecycle.	Not a current basis; old closed tables cannot be relabelled as 2025 values.

Review notes

Why does this page no longer output Zone A, B, C or D?

The prior numbers had no licensed current table, measurement position, direction, band, fixed period, operating-state or boundary-convention evidence. Publishing a zone would therefore be an unsupported safety-relevant claim.

Can a zone diagnose a bearing or gearbox fault?

No. The official public abstract says the document does not address diagnosis or fault detection and that evaluation zones are generally unsuitable for early fault detection.

Does turbine power class select a universal limit?

No such public rule was verified. The current public scope says rated output exceeds 200 kW, while publicly described Annex A data come from turbines rated 5 MW or less. The protected procedure and licensed data control any further use.

Can this worksheet recommend shutdown or continued operation?

No. Operational decisions require the licensed criteria, site and manufacturer limits, the correct measurement context, trend and corroborating evidence, and accountable qualified review.

Source access: 17 July 2026. No closed ISO table, clause text, coefficient or numeric boundary is copied or inferred. The previous 24 triplets, automatic zones, diagnostic messages and operating instructions were removed because their current normative basis was not verified.

Wind Turbine Vibration Evaluation Evidence Worksheet

Evaluation-evidence record

Not assessed

What the public record establishes

Standard and source register

Review notes