# ANSI/IEEE shielded conductor symbol

Canonical URL: https://eloragrid.ai/symbols/ansi-shielded-conductor
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: W
Drawing use: Schematic
Reference families: IEEE / ANSI

## Symbol convention

Convention: IEEE / ANSI
Form: Shielded conductor with broken enclosure
Independent illustration in IEEE drafting context; no equivalence of every detailed standard graphic is asserted.

IEEE-oriented shielded conductor drawn with a dashed or broken outline around the wire to show a shield.

## In plain English

### What does ANSI/IEEE shielded conductor mean?

In IEEE-oriented drawings a shielded conductor is commonly shown with a broken or dashed enclosure around the conductor, sometimes with a short lead to a ground symbol. US instrumentation drawings use it for analogue signal wiring, thermocouple extension leads and drive feedback.

### A simple example

This is an independently drawn explanation of the convention, not a reproduction of the IEEE graphic. As with the IEC form, the outline does not say where the shield is grounded, which must be shown at the shield lead. Shield drain wires should have their own terminal numbers.

### What the drawings help you do

Locate the shield drain termination. Check whether the shield is grounded at one end only. A shielded conductor intercepts interference; a coaxial cable uses its outer conductor as the signal return.

### This particular reference

IEEE-oriented shielded conductor drawn with a dashed or broken outline around the wire to show a shield. A shielded conductor intercepts interference; a coaxial cable uses its outer conductor as the signal return.

### Terms

- Terminal: An identified point where a conductor connects.
- Signal: Electrical information passed between devices, rather than necessarily the main power supply.
- 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.

- [IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams](https://standards.ieee.org/ieee/315/515/)
- [Autodesk IEEE Symbol Preview — Miscellaneous](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-34282BFD-7B8E-48F3-A6ED-93ADBDDDFBD3.htm)


## What it represents

In IEEE-oriented drawings a shielded conductor is commonly shown with a broken or dashed enclosure around the conductor, sometimes with a short lead to a ground symbol. US instrumentation drawings use it for analogue signal wiring, thermocouple extension leads and drive feedback.
This is an independently drawn explanation of the convention, not a reproduction of the IEEE graphic. As with the IEC form, the outline does not say where the shield is grounded, which must be shown at the shield lead. Shield drain wires should have their own terminal numbers.

## How to read it

- Locate the shield drain termination.
- Check whether the shield is grounded at one end only.

## Information to show or reference

- Show the shield ground point.
- Assign terminal numbers to drain wires.
- Record shield type in the cable schedule.

## Important distinction

A shielded conductor intercepts interference; a coaxial cable uses its outer conductor as the signal return.

## Facts

- Convention evidence: IEEE 315 graphic conventions for shielded conductors (standards context only)
- Standards context: IEEE/ANSI 315-1975 covers diagram graphics; IEEE lists this edition as Inactive-Reserved.
- Preview: Original educational illustration; consult the publisher and applicable standard for the exact graphic

## Public references

- [IEEE/ANSI 315-1975: graphic symbols for electrical and electronics diagrams](https://standards.ieee.org/ieee/315/515/) — IEEE Standards Association. Graphic-symbol standards context and official status; not a source of reproduced artwork.
- [Autodesk IEEE Symbol Preview — Miscellaneous](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-34282BFD-7B8E-48F3-A6ED-93ADBDDDFBD3.htm) — Autodesk. Public IEEE-oriented earth forms used on shield drains.

## 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.