# Differential voltmeter

Canonical URL: https://eloragrid.ai/symbols/differential-voltmeter
Publisher: Elora Grid
Updated: 2026-10-13
Lookup label: DELTA V
Drawing use: SLD, Schematic
Reference families: IEC, Manufacturer

A differential voltmeter indicates a difference between documented voltage inputs.

## What it represents

A differential voltmeter indicates a difference between documented voltage inputs. Its reference and compared circuits must be identifiable so the indicated difference has a defined meaning.

## How to read it

- Verify the input connection arrangement against the actual instrument diagram.
- 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

- Identify both compared inputs
- State polarity/reference
- Reference measurement range

## Important distinction

A differential voltage indicator is different from a transformer differential protection function.

## Facts

- Drawing role: Indicated quantity
- Representation scope: Functional concept; not an official standard graphic or a product footprint
- Public vendor block reference: HVM1P7, VVM1P7 (Autodesk identifiers; not IEC symbol numbers)
- 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

- [AutoCAD Electrical: Instrumentation and sensors](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-773A36C3-44C6-43EB-9BD0-E0297816B9B2.htm) — Autodesk. 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.