# Busway end feed unit

Canonical URL: https://eloragrid.ai/symbols/busway-end-feed-unit
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: EF
Drawing use: SLD, GA
Reference families: IEC, IEEE / ANSI, Manufacturer

The point where incoming cables or a transformer connect to the end of a busway run, drawn as a feed box on the busway.

## In plain English

### What does Busway end feed unit mean?

An end feed unit is the cable or transformer connection box at the start of a busway run. On single-line diagrams it shows where the supply enters the busway and is often annotated with the incoming cable details. Centre feed units, used to reduce voltage drop on long runs, are a related variant.

### A simple example

The symbol does not show whether the feed unit includes isolation. Many end feed units are simple cable boxes, so isolation for maintenance must be at the upstream switchboard. Check cable entry and gland plate sizes on the layout, because large parallel cable sets need substantial space.

### What the drawings help you do

Confirm where isolation for the busway is provided. Read incoming cable data at the feed unit. An end feed unit brings supply into the busway; a tap-off connection takes supply out of it.

### This particular reference

The point where incoming cables or a transformer connect to the end of a busway run, drawn as a feed box on the busway. An end feed unit brings supply into the busway; a tap-off connection takes supply out of it.

### Terms

- Winding: A coil of conductor inside an electrical machine or transformer.
- Terminal: An identified point where a conductor connects.
- Rating: A value stating the conditions for which equipment is specified.

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.

- [Canalis busbar trunking systems](https://www.se.com/ww/en/work/products/master-ranges/line-series/)
- [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

An end feed unit is the cable or transformer connection box at the start of a busway run. On single-line diagrams it shows where the supply enters the busway and is often annotated with the incoming cable details. Centre feed units, used to reduce voltage drop on long runs, are a related variant.
The symbol does not show whether the feed unit includes isolation. Many end feed units are simple cable boxes, so isolation for maintenance must be at the upstream switchboard. Check cable entry and gland plate sizes on the layout, because large parallel cable sets need substantial space.

## How to read it

- Confirm where isolation for the busway is provided.
- Read incoming cable data at the feed unit.

## Information to show or reference

- Show the incoming cable or transformer connection.
- Identify upstream isolation.
- Reference the feed unit size and cable entry.

## Important distinction

An end feed unit brings supply into the busway; a tap-off connection takes supply out of it.

## Facts

- Graphic cue: Box at the end of a busway with incoming conductors
- Variant: Centre feed units exist for long runs
- Preview: Original educational illustration; consult the publisher and applicable standard for the exact graphic

## Public references

- [Canalis busbar trunking systems](https://www.se.com/ww/en/work/products/master-ranges/line-series/) — Schneider Electric. Manufacturer busbar trunking ranges including feed units.
- [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.