# ANSI/IEEE normally closed pushbutton symbol

Canonical URL: https://eloragrid.ai/symbols/ansi-pushbutton-nc
Publisher: Elora Grid
Updated: 2026-10-14
Lookup label: PB NC
Drawing use: Schematic
Reference families: IEEE / ANSI, Manufacturer

## Symbol convention

Convention: IEEE / ANSI
Form: Autodesk IEEE-oriented Push Buttons 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: [Normally closed pushbutton](https://eloragrid.ai/symbols/pushbutton-nc)

IEEE-oriented graphical reference for normally closed pushbutton, with public vendor evidence and drawing-reading notes.

## What it represents

The momentary NC pushbutton form describes a normally continuous path opened by the operator. Its circuit role can be stop, inhibit or another command, but that purpose comes from the wiring and label rather than from NC alone.
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

- Evaluate the path before, during and after operation.
- 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

- Name commanded function
- Show terminal pair
- State return behaviour

## Important distinction

An NC contact form does not by itself identify a complete emergency-stop safety circuit.

## Facts

- Convention evidence: Autodesk IEEE Symbol Preview — Push Buttons
- Public vendor block name: HPB12 (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 — Push Buttons](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-863A2EB5-8ECD-4348-90C7-49A37DE11B8B.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.