Overhead Lines

Overhead lines are the catenary that carries power above the track. An overhead line reading captures the measured condition of the contact wire at a single point: how high it sits, how thick it is, and how far it staggers from centre. Each reading is taken during a measurement run as the vehicle travels along the line.

At a glance

• Represents: a single catenary (contact-wire) measurement reading
• Body shape: a JSON array of reading objects
• Keyed by: the measurement run it belongs to, the track, and where along the track it was taken
• Belongs to: a measurement run (measurementRunId)

Tip

The full field list, required vs. optional flags, and a runnable example payload are in the API Reference under Overhead Line Import.

What it represents

The condition values describe the wire itself:

• Height above the track.
• Thickness — wear shows up as the wire gets thinner.
• Stagger — the sideways offset from the track centreline that spreads pantograph wear evenly.

These values are optional; you send whatever the run captured.

Each reading is anchored by when and where it was taken: the date and time, together with a track and a chainage along that track. Rather than a full geolocation block, an overhead line reading positions itself by a simple linear reference — a track code and a distance along it — which the platform resolves to a point on the network. See how geolocation is shared across other models for the fuller positioning concept.

Using it

• Readings are grouped by measurement run: the same measurementRunId ties together every reading produced by one pass along the line.
• Send readings in bulk — one call can carry a single reading or a whole run’s worth.
• The track code must be one the platform can geolocate against. A reference it doesn’t recognise surfaces at job time. See Common Errors.
• Importing is an upsert keyed by the run, track, and chainage, so re-sending a run is safe.