# Fast earthing-switch functional reference

Canonical URL: https://eloragrid.ai/symbols/fast-earthing-switch-functional-reference
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: FEFR
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: switchyards
Input: Assigned fast-earth command
Output: Fast earthing action

Identifies the assigned high-speed earthing function in its documented primary application.

## In plain English

### What this block does

Identifies the assigned high-speed earthing function in its documented primary application.

### A simple example

In a switchyard bay, a bus selector can use a different physical construction from a line disconnector. Each device still needs an identified operating mechanism, position indication and interlocking interface. For this reference, the drawing identifies “Assigned fast-earth command” at the input and “Fast earthing action” at the output. Making duty and application require equipment-specific validation.

### What the drawings help you do

Start at the named input: Assigned fast-earth command. Identify its source device or document and the state represented on the drawing. Follow the named output: Fast earthing action. Cross-reference its destination and separate the command from confirmation that the equipment responded.

### Terms

- Input: Assigned fast-earth command
- Output: Fast earthing action
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: Assigned fast-earth command → FEFR → Fast earthing action
A reading guide. The entry's original illustration and input/output facts describe this application.

- [Disconnectors and earthing switches](https://www.siemens-energy.com/global/en/home/products-services/product-offerings/disconnectors-earthing-switches.html)


## What it represents

Identifies the assigned high-speed earthing function in its documented primary application. Disconnector and earthing references identify different mechanical constructions and connection duties within a yard. The primary diagram shows which conductors are joined or earthed; the equipment drawing explains how its contacts and supports move.
In a switchyard bay, a bus selector can use a different physical construction from a line disconnector. Each device still needs an identified operating mechanism, position indication and interlocking interface. For this reference, the drawing identifies “Assigned fast-earth command” at the input and “Fast earthing action” at the output. Making duty and application require equipment-specific validation.
The construction name does not establish load-breaking capability, short-circuit making duty or operating permission. Verify these properties in the selected equipment data and the station interlocking scheme. The functional block is an independent explanation of this named application. Equipment-specific ratings, terminal connections and operating conditions must be established in the project documentation.

## How to read it

- Start at the named input: Assigned fast-earth command. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Fast earthing action. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Making duty and application require equipment-specific validation.
- The construction name does not establish load-breaking capability, short-circuit making duty or operating permission. Verify these properties in the selected equipment data and the station interlocking scheme.

## Information to show or reference

- Label the source and connection reference for assigned fast-earth command.
- Identify the destination and defined state of fast earthing action.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Making duty and application require equipment-specific validation.

## Important distinction

Making duty and application require equipment-specific validation. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.

## Facts

- Representation: Functional block
- Installation focus: Switchyards
- Input / boundary: Assigned fast-earth command
- Output / connection: Fast earthing action
- Lookup label: FEFR is a library lookup label, not a standard device designation.

## Public references

- [Disconnectors and earthing switches](https://www.siemens-energy.com/global/en/home/products-services/product-offerings/disconnectors-earthing-switches.html) — Siemens Energy. Public technical context for disconnector and earthing applications. Disconnector construction, earthing switches and operating mechanisms. The application text and educational graphic are independently authored; the publisher does not certify this representation.

## 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.