# Time-delay push switch plan mark

Canonical URL: https://eloragrid.ai/symbols/iec-time-delay-push-switch
Publisher: Elora Grid
Updated: 2026-10-28
Lookup label: ST
Drawing use: GA
Reference families: IEC

## Symbol convention

Convention: IEC
Form: Time-delay push switch
IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier.

Plan mark for a push switch that turns lights on for a set period, commonly used in stairwells and common corridors.

## In plain English

### What does Time-delay push switch plan mark mean?

A time-delay push switch, often wired to a staircase timer, turns lighting on when pressed and lets it switch off after a set interval. Plans draw a push-button mark at each push position with a small clock or t tag, and show the timer location in the board where one is used.

### A simple example

Several push switches may be wired in parallel to one timer, so the switching line links them all to a common luminaire group. The electrician reads the plan to run a separate push conductor rather than switched-line wiring.

### What the drawings help you do

The plan symbol does not set the delay period or state whether the timer is in the switch or at the board. The specification should give both.

### This particular reference

Plan mark for a push switch that turns lights on for a set period, commonly used in stairwells and common corridors. A momentary bell push is not connected to lighting; a time-delay push switch starts a lighting timer.

### Terms

- Terminal: An identified point where a conductor connects.
- 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/)
- [Elementary switching devices](https://www.electrical-installation.org/enwiki/Elementary_switching_devices)


## What it represents

A time-delay push switch, often wired to a staircase timer, turns lighting on when pressed and lets it switch off after a set interval. Plans draw a push-button mark at each push position with a small clock or t tag, and show the timer location in the board where one is used.
Several push switches may be wired in parallel to one timer, so the switching line links them all to a common luminaire group. The electrician reads the plan to run a separate push conductor rather than switched-line wiring.
The plan symbol does not set the delay period or state whether the timer is in the switch or at the board. The specification should give both.

## How to read it

- Look for the associated timer in the board schedule.
- Expect several pushes wired in parallel on one landing group.

## Information to show or reference

- State delay time and adjustment range.
- Show the timer location.
- Link all pushes to the controlled group.

## Important distinction

A momentary bell push is not connected to lighting; a time-delay push switch starts a lighting timer.

## Facts

- Operation: Momentary push starting a timed lighting period
- Typical location: Stairs and shared corridors
- Exact standard graphic: Not reproduced here; confirm the form against IEC 60617 and the project legend

## Public references

- [IEC graphical symbols for diagrams](https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/) — IEC. IEC graphical symbol context; independently drawn here.
- [Elementary switching devices](https://www.electrical-installation.org/enwiki/Elementary_switching_devices) — Schneider Electric — Electrical Installation Guide. Context for functional control switching.

## 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.