# Alternating bidirectional propagation qualifier

Canonical URL: https://eloragrid.ai/symbols/iec-alternating-bidirectional-propagation-qualifier
Publisher: Elora Grid
Updated: 2026-10-14
Lookup label: Q020503
Drawing use: Schematic
Reference families: IEC, Manufacturer

## Symbol convention

Convention: IEC
Form: Alternating bidirectional propagation qualifier
Autodesk IEC-60617 Symbol Preview — Propagation and signal-flow qualifiers; vendor family reference, not certified IEC geometry or database identifier.

This qualifier identifies opposite-direction propagation occurring alternately.

## What it represents

This qualifier identifies opposite-direction propagation occurring alternately. The two directions are used at different times, making the temporal relationship different from simultaneous two-way propagation. The underlying link can still appear as a single path.
Record which functions send and receive and how the documented operation changes direction. Do not interpret the qualifier as two independent physical cables.

## How to read it

- Describe the direction-changing or turn-taking arrangement separately.
- Alternating bidirectional propagation differs from simultaneous bidirectional transmission.

## Information to show or reference

- Identify the associated device, circuit or diagram boundary.
- Describe the direction-changing or turn-taking arrangement separately.
- Cross-reference the equipment data, terminal mapping or operating-state legend needed to interpret the form.

## Important distinction

Alternating bidirectional propagation differs from simultaneous bidirectional transmission.

## Facts

- Reference scope: Specific public IEC-context family form
- Publisher reference token: Q020503 (Autodesk token; not a verified IEC database ID)
- Information added: Describe the direction-changing or turn-taking arrangement separately.
- Preview: Independent educational concept; consult the publisher and applicable standard for the exact graphic

## Public references

- [Autodesk IEC-60617 preview: Propagation and signal-flow qualifiers](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-1C0C7AE2-F703-4283-BCB1-3E0B30882715.htm) — Autodesk. Official public publisher family name and reference context; vendor identifiers and graphics are distinct from licensed IEC database content.

## Graphic scope

Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.