# Three-phase circuit with neutral and PE marking

Canonical URL: https://eloragrid.ai/symbols/iec-three-phase-five-wire-marking
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: 3/N/PE
Drawing use: SLD
Reference families: IEC

## Symbol convention

Convention: IEC
Form: Conductor complement notation on a single line
Independent IEC-context illustration; not certified IEC geometry.

A single-line notation such as 3/N/PE showing a three-phase circuit carrying both a neutral and a separate protective conductor.

## In plain English

### What does Three-phase circuit with neutral and PE marking mean?

Single-line diagrams often state the conductor complement of a circuit with a short notation beside the line, for example 3/N/PE 400/230 V 50 Hz. This tells the reader at a glance that the circuit has three phases, a neutral and a separate protective conductor, which is the normal TN-S final distribution arrangement.

### A simple example

The notation is a statement about which conductors exist, not their sizes. It also does not confirm that the downstream equipment uses the neutral. Changes in the notation along a feeder, for example from 3/PEN to 3/N/PE, mark the point where a PEN conductor has been split.

### What the drawings help you do

Watch for a change in notation along a feeder that marks a PEN split. Read voltage and frequency that may follow the conductor notation. The 3/N/PE notation states a whole conductor complement; individual N, PE or PEN marks identify one conductor on a stroke.

### This particular reference

A single-line notation such as 3/N/PE showing a three-phase circuit carrying both a neutral and a separate protective conductor. The 3/N/PE notation states a whole conductor complement; individual N, PE or PEN marks identify one conductor on a stroke.

### Terms

- Phase: One of the related AC waveforms in a power system.
- Schematic: A drawing showing function and connections rather than physical appearance.

Concept diagram: Identify the device and form → Read the connections and state → Check the equipment reference
A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.

- [Definition of standardised earthing schemes](https://www.electrical-installation.org/enwiki/Definition_of_standardised_earthing_schemes)
- [IEC-60617 symbol preview directory](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-7871E6EF-24D5-467E-9B74-321FEDC9DFDA.htm)


## What it represents

Single-line diagrams often state the conductor complement of a circuit with a short notation beside the line, for example 3/N/PE 400/230 V 50 Hz. This tells the reader at a glance that the circuit has three phases, a neutral and a separate protective conductor, which is the normal TN-S final distribution arrangement.
The notation is a statement about which conductors exist, not their sizes. It also does not confirm that the downstream equipment uses the neutral. Changes in the notation along a feeder, for example from 3/PEN to 3/N/PE, mark the point where a PEN conductor has been split.

## How to read it

- Watch for a change in notation along a feeder that marks a PEN split.
- Read voltage and frequency that may follow the conductor notation.

## Information to show or reference

- State the conductor complement on each distribution feeder.
- Include voltage and frequency where the notation is used.
- Keep notation consistent with the cable schedule.

## Important distinction

The 3/N/PE notation states a whole conductor complement; individual N, PE or PEN marks identify one conductor on a stroke.

## Facts

- Typical text: 3/N/PE 400/230 V 50 Hz
- Scheme context: TN-S distribution
- Preview: Original educational illustration; consult the publisher and applicable standard for the exact graphic

## Public references

- [Definition of standardised earthing schemes](https://www.electrical-installation.org/enwiki/Definition_of_standardised_earthing_schemes) — Schneider Electric, Electrical Installation Guide. Public installation-guide definitions of earthing schemes.
- [IEC-60617 symbol preview directory](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-7871E6EF-24D5-467E-9B74-321FEDC9DFDA.htm) — Autodesk. Public directory of IEC-oriented symbol families.

## 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.