# PLC analog input

Canonical URL: https://eloragrid.ai/symbols/plc-analog-input
Publisher: Elora Grid
Updated: 2026-10-13
Lookup label: AI
Drawing use: Schematic
Reference families: Manufacturer

A PLC analog input measures a documented voltage, current or sensor quantity.

## What it represents

A PLC analog input measures a documented voltage, current or sensor quantity. Its signal range, common and any shield/earth connection require explicit wiring information.

## How to read it

- Identify the selected channel mode before interpreting its terminals.
- The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation.

## Information to show or reference

- State signal type/range
- Show signal common and shield
- Reference channel configuration

## Important distinction

Analog measurement carries a range of values; a digital input reads a discrete state.

## Facts

- Drawing role: Controller interface
- Representation scope: Functional concept; not an official standard graphic or a product footprint
- Identifier status: The short label is a functional lookup label, not an assigned IEC or IEEE symbol number. Any separately listed Autodesk code is a verified vendor block name.

## Public references

- [Modicon TM3 analog I/O hardware guide](https://www.se.com/us/en/download/document/EIO0000003131/) — Schneider Electric. Public documentation of this equipment function or named vendor variant; the illustration is independently authored and is not the source graphic.

## 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.