# Switchroom environmental alarm delay block

Canonical URL: https://eloragrid.ai/symbols/switchroom-environmental-alarm-delay-block
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: SEADB
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: switchrooms
Input: Environmental threshold state
Output: Delayed alarm output

Applies the documented persistence interval to the assigned environmental alarm condition.

## In plain English

### What this block does

Applies the documented persistence interval to the assigned environmental alarm condition.

### A simple example

In a switchroom, water ingress, temperature, humidity and equipment-service alarms can be sent to the station controller with separate point names so an operator can identify the affected area. For this reference, the drawing identifies “Environmental threshold state” at the input and “Delayed alarm output” at the output. Delay must not hide an unacceptable operating condition.

### What the drawings help you do

Start at the named input: Environmental threshold state. Identify its source device or document and the state represented on the drawing. Follow the named output: Delayed alarm output. Cross-reference its destination and separate the command from confirmation that the equipment responded.

### Terms

- Input: Environmental threshold state
- Output: Delayed alarm output
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: Environmental threshold state → SEADB → Delayed alarm output
A reading guide. The entry's original illustration and input/output facts describe this application.

- [Ventilation in MV substations](https://www.electrical-installation.org/enwiki/Ventilation_in_MV_Substations)


## What it represents

Applies the documented persistence interval to the assigned environmental alarm condition. Environmental supervision turns measurements or contact states into clearly named room-service indications. A sensor measures a condition; the supervisory function decides whether the assigned alarm or control response is needed.
In a switchroom, water ingress, temperature, humidity and equipment-service alarms can be sent to the station controller with separate point names so an operator can identify the affected area. For this reference, the drawing identifies “Environmental threshold state” at the input and “Delayed alarm output” at the output. Delay must not hide an unacceptable operating condition.
Keep sensor location, alarm thresholds, delay and monitoring coverage in the room-services schedule. An environmental alarm is a diagnostic input, not a complete assessment of electrical equipment condition. The functional block is an independent explanation of this named application. Equipment-specific ratings, terminal connections and operating conditions must be established in the project documentation.

## How to read it

- Start at the named input: Environmental threshold state. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Delayed alarm output. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Delay must not hide an unacceptable operating condition.
- Keep sensor location, alarm thresholds, delay and monitoring coverage in the room-services schedule. An environmental alarm is a diagnostic input, not a complete assessment of electrical equipment condition.

## Information to show or reference

- Label the source and connection reference for environmental threshold state.
- Identify the destination and defined state of delayed alarm output.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Delay must not hide an unacceptable operating condition.

## Important distinction

Delay must not hide an unacceptable operating condition. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.

## Facts

- Representation: Functional block
- Installation focus: Switchrooms
- Input / boundary: Environmental threshold state
- Output / connection: Delayed alarm output
- Lookup label: SEADB is a library lookup label, not a standard device designation.

## Public references

- [Ventilation in MV substations](https://www.electrical-installation.org/enwiki/Ventilation_in_MV_Substations) — Schneider Electric. Public technical context for switchroom environmental supervision. Heat removal, condensation and environmental design context. The application text and educational graphic are independently authored; the publisher does not certify this representation.

## 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.