# Voltage transformer with two secondary windings

Canonical URL: https://eloragrid.ai/symbols/voltage-transformer-with-two-secondaries
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: VT
Drawing use: SLD, Schematic
Reference families: IEC, Manufacturer

VT with two separate secondary windings, typically one for metering and one for protection, each with its own fusing.

## In plain English

### What does Voltage transformer with two secondary windings mean?

This VT form has one primary and two secondary windings. The usual arrangement gives a metering winding with a high accuracy class and a protection winding, each fused or protected by an MCB separately so a fault on one circuit does not take out the other.

### A simple example

Both windings share the same core, so their combined burden must stay within the VT's thermal rating. The symbol shows the two windings but not the class of each or the secondary protection, which must be stated for each circuit.

### What the drawings help you do

Read the class and burden of each winding. Find the separate secondary protection for each winding. A VT with two secondaries shares one core; two separate VTs give independent cores.

### This particular reference

VT with two separate secondary windings, typically one for metering and one for protection, each with its own fusing. A VT with two secondaries shares one core; two separate VTs give independent cores.

### Terms

- Winding: A coil of conductor inside an electrical machine or transformer.
- Rating: A value stating the conditions for which equipment is specified.
- 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.

- [Indoor current and voltage transformers](https://www.abb.com/gb/en/areas/electrification/medium-voltage/grid-components/core-components/indoor-instrument-transformers)
- [Power, potential and autotransformer symbols](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-C1FE1690-DBF4-4F69-85C4-28E41F0A6392.htm)


## What it represents

This VT form has one primary and two secondary windings. The usual arrangement gives a metering winding with a high accuracy class and a protection winding, each fused or protected by an MCB separately so a fault on one circuit does not take out the other.
Both windings share the same core, so their combined burden must stay within the VT's thermal rating. The symbol shows the two windings but not the class of each or the secondary protection, which must be stated for each circuit.

## How to read it

- Read the class and burden of each winding.
- Find the separate secondary protection for each winding.

## Information to show or reference

- State class per winding
- Show secondary fusing per winding
- Reference earthing point

## Important distinction

A VT with two secondaries shares one core; two separate VTs give independent cores.

## Facts

- Windings: One primary, two secondaries
- Typical split: Metering and protection
- Preview: Independent educational concept; consult the applicable standard and project legend for the exact graphic

## Public references

- [Indoor current and voltage transformers](https://www.abb.com/gb/en/areas/electrification/medium-voltage/grid-components/core-components/indoor-instrument-transformers) — ABB. Public manufacturer overview of indoor current and voltage instrument transformers.
- [Power, potential and autotransformer symbols](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-C1FE1690-DBF4-4F69-85C4-28E41F0A6392.htm) — Autodesk. Public potential-transformer symbol family used for context.

## 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.