# ANSI/IEEE lockable switch-disconnector symbol

Canonical URL: https://eloragrid.ai/symbols/ansi-lockable-switch-disconnector
Publisher: Elora Grid
Updated: 2026-10-14
Lookup label: SD LOCK
Drawing use: SLD, Schematic
Reference families: IEEE / ANSI, Manufacturer

## Symbol convention

Convention: IEEE / ANSI
Form: Autodesk IEEE-oriented Disconnect 1 Pole functional form
Autodesk explicitly publishes this block under IEEE Symbol Preview. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.
Related representation: [Lockable switch-disconnector](https://eloragrid.ai/symbols/lockable-switch-disconnector)

IEEE-oriented graphical reference for lockable switch-disconnector, with public vendor evidence and drawing-reading notes.

## What it represents

The lockable switch-disconnector form combines load switching, isolation and a documented locking provision. These are separate capabilities recorded against the same device, rather than inferred from a single contact gap or padlock outline.
This is a convention-specific lookup based on the publisher's IEEE-labelled preview. The geometry here is independently drawn to explain the connection or operation; it is not a certified reproduction of the standard graphic.

## How to read it

- Identify the permitted locking state in the operator schedule.
- Read the selected library and the project legend together. A vendor block identifier is meaningful within its named library and is not a universal standard-symbol code.

## Information to show or reference

- Record switching duty
- State locking position
- Reference handle arrangement

## Important distinction

Adding a locking modifier to a switch does not prove that it has the isolation function of a switch-disconnector.

## Facts

- Convention evidence: Autodesk IEEE Symbol Preview — Disconnect 1 Pole
- Public vendor block name: HDS11Q77 (Autodesk identifier; not an IEEE symbol number)
- Standards context: IEEE/ANSI 315-1975 covers diagram graphics. IEEE lists this edition as Inactive-Reserved.
- Artwork scope: Original functional illustration; exact standard glyph and compliance are not certified

## Public references

- [Autodesk IEEE Symbol Preview — Disconnect 1 Pole](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-7C62D3DE-6494-4CBF-B3CF-3E3DA309D6A4.htm) — Autodesk. Exact public IEEE-oriented category page verifying the component name and vendor block identifier.
- [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.

## 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.