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OpenCDD

IEC CDD records every published revision of every entity — version number, status, timestamp, the change-request ID that introduced it, and the user who committed it. OpenCDD captures this chain of custody from cdd.iec.ch and exposes it on every entity that has multiple versions.

What’s on the page

Every entity detail page in the browser ends with a Version history section. Each version appears as a vertical timeline entry, styled as an archival specimen record:

  • A large serif version numeral (e.g. 003).
  • A wax-seal status pill — amber for the current version, emerald for standard, grey for superseded.
  • A notary signature row showing the timestamp and the user/batch that committed the revision.
  • The change request ID rendered as a museum catalog number.

For entities with more than one version, each non-current entry also offers:

  • View this version — fetches the historical JSON and applies a subtle aged-paper treatment to the page. The URL becomes ?v=<unid> for shareability. A “Return to current” button restores the live view.
  • Diff vs current — opens a modal showing the field-level differences between the historical version and the current one, with unified and split modes.

Keyboard navigation

The timeline supports full keyboard control:

Key Action
ArrowDown / ArrowRight Move to next entry
ArrowUp / ArrowLeft Move to previous entry
Home / End Jump to first / last entry
Enter View the focused version
d Diff the focused version against current

Per-version downloads

Each version entry has a “Version JSON” link that downloads the historical JSON for that specific version. Use this to compare revisions offline or feed them into a custom analysis pipeline.

What’s stored

The JSON payload on every entity carries a version_history array. Each entry has:

{
  "version": "002",
  "revision": "01",
  "status": "superseded",
  "timestamp": "2022-07-25 19:42:07",
  "user": "BATCH 00000919",
  "change_request_id": null,
  "unid": "c7b602fc5672a876c125888a00613da8",
  "is_current": false
}

For historical versions where the scraper didn’t capture the raw .xls exports (the common case), the version JSON is metadata-only. The browser shows an amber “Metadata-only view” notice when this happens; the full record can be fetched from cdd.iec.ch directly. section: “Guides”