# IEC integrator element (∫)

Canonical URL: https://eloragrid.ai/symbols/iec-integrator
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: ∫
Drawing use: Schematic
Reference families: IEC, Manufacturer

## Symbol convention

Convention: IEC
Form: Rectangular analogue element with integral sign
IEC-style rectangular analogue element presentation; the IEC graphical symbols programme is cited for context only. Independent educational drawing; not certified IEC geometry or an IEC database identifier. The counterpart is the matching functional concept; no equivalence of every detailed standard graphic is asserted.
Related representation: [Op-amp integrator](https://eloragrid.ai/symbols/op-amp-integrator)

Analogue element marked with an integral sign; the output is proportional to the time integral of the input.

## In plain English

### What does IEC integrator element (∫) mean?

The integrator element shows the integral sign inside a rectangular analogue element, usually with an amplifier mark. Its output changes at a rate proportional to the input, so a constant input produces a ramp. Reset or initial-condition inputs may be added to set the starting value.

### A simple example

Integrators appear in PI controllers, ramp generators and charge measurement. On the drawing, the time constant and any reset arrangement should be stated, because without them the element can drift to saturation.

### What the drawings help you do

The element does not specify the realisation. An op-amp with a feedback capacitor is common, but digital integration in a controller is drawn the same way on functional diagrams.

### This particular reference

Analogue element marked with an integral sign; the output is proportional to the time integral of the input. The differentiator element uses d/dt and responds to rate of change rather than accumulated value.

### Terms

- Signal: Electrical information passed between devices, rather than necessarily the main power supply.
- 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.

- [IEC graphical symbols for diagrams](https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/)
- [Integrator circuit reference, SBOA275](https://www.ti.com/lit/pdf/sboa275)


## What it represents

The integrator element shows the integral sign inside a rectangular analogue element, usually with an amplifier mark. Its output changes at a rate proportional to the input, so a constant input produces a ramp. Reset or initial-condition inputs may be added to set the starting value.
Integrators appear in PI controllers, ramp generators and charge measurement. On the drawing, the time constant and any reset arrangement should be stated, because without them the element can drift to saturation.
The element does not specify the realisation. An op-amp with a feedback capacitor is common, but digital integration in a controller is drawn the same way on functional diagrams.

## How to read it

- Look for a reset or initial condition input.
- Find the time constant in notes or component values.

## Information to show or reference

- State the time constant.
- Show reset or limit arrangements.
- Reference the implementing circuit or function block.

## Important distinction

The differentiator element uses d/dt and responds to rate of change rather than accumulated value.

## Facts

- Function: Time integral of input
- Required data: Time constant and reset
- Artwork scope: Original educational illustration; consult the applicable standard and the selected device documentation for the exact graphic

## Public references

- [IEC graphical symbols for diagrams](https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/) — IEC. IEC graphical symbols programme covering analogue elements; no geometry reproduced.
- [Integrator circuit reference, SBOA275](https://www.ti.com/lit/pdf/sboa275) — Texas Instruments. Manufacturer integrator circuit documentation.

## 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.