# Turning-gear engaging device

Canonical URL: https://eloragrid.ai/protection-functions/54-turning-gear-engaging-device
Publisher: Elora Grid
Updated: 2026-10-13
Lookup label: 54
Drawing use: SLD, Schematic
Reference families: IEEE / ANSI

Controls engagement of the turning gear used to rotate a large machine at low speed.

## What it represents

Controls engagement of the turning gear used to rotate a large machine at low speed.
In a drafting package, connect this reference to the turning-gear mechanism and speed/interlock signals. The associated drawing should trace the engagement actuator and proof-of-position circuit; the number identifies the role and does not specify the terminal arrangement, ratings or operating settings.
This designation is useful when reading machine and legacy control drawings. Retain the documented function on an existing drawing and consult the original equipment manual before assigning it to a new design.

## How to read it

- Identify the turning-gear mechanism and speed/interlock signals.
- Trace the engagement actuator and proof-of-position circuit.

## Information to show or reference

- Label the turning-gear mechanism and speed/interlock signals.
- Cross-reference the engagement actuator and proof-of-position circuit.
- Identify the device tag, manual revision and logic drawing that define this implementation.

## Important distinction

Turning-gear engagement is a specialist machine mechanism, not a bus or generator paralleling breaker.

## Facts

- ANSI / IEEE function number: 54
- Drawing context: The turning-gear mechanism and speed/interlock signals
- Application scope: Specialist or legacy machine-control use; interpret with the equipment legend.

## Public references

- [SecoGear medium-voltage switchgear application and technical guide, DET-882](https://library.e.abb.com/public/a06cf4cf38b34800b27bb337ab12f74f/DET-882%20SecoGear%205kV-15kV%20IEEE%20Metal%20Clad%20Switchgear_Application%20and%20installation%20guide.pdf) — ABB. Public manufacturer number/name association. Drafting explanations are independently written.
- [IEEE C37.2-2022: power-system device function numbers](https://ieeexplore.ieee.org/document/9984140) — IEEE. Normative device-number publication; exact edition wording and compliance require the licensed standard.

## 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.