# Incomer transfer-in-progress indication

Canonical URL: https://eloragrid.ai/symbols/incomer-transfer-in-progress-indication
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: ITI
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: switchgear
Input: Transfer state machine
Output: Transfer-active status

Reports that the documented source-transfer sequence is active and not yet complete.

## In plain English

### What this block does

Reports that the documented source-transfer sequence is active and not yet complete.

### A simple example

In a switchgear lineup with two incomers and a bus tie, the single-line arrangement helps the engineer identify normal supply paths and which loads change source during a transfer. For this reference, the drawing identifies “Transfer state machine” at the input and “Transfer-active status” at the output. Intermediate states need explicit indication.

### What the drawings help you do

Start at the named input: Transfer state machine. Identify its source device or document and the state represented on the drawing. Follow the named output: Transfer-active status. Cross-reference its destination and separate the command from confirmation that the equipment responded.

### Terms

- Input: Transfer state machine
- Output: Transfer-active status
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: Transfer state machine → ITI → Transfer-active status
A reading guide. The entry's original illustration and input/output facts describe this application.

- [SEL-451 protection, automation and bay control](https://selinc.com/products/451/)


## What it represents

Reports that the documented source-transfer sequence is active and not yet complete. A source and bus arrangement shows how incoming supplies and outgoing circuits can be connected. Breaker and tie positions determine which sections are energized and whether sources can become electrically paralleled.
In a switchgear lineup with two incomers and a bus tie, the single-line arrangement helps the engineer identify normal supply paths and which loads change source during a transfer. For this reference, the drawing identifies “Transfer state machine” at the input and “Transfer-active status” at the output. Intermediate states need explicit indication.
Keep normal positions, transfer limits, source independence and protection-zone boundaries visible. An arrangement drawing explains connectivity; the permitted switching sequence needs a separate approved scheme. 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: Transfer state machine. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Transfer-active status. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Intermediate states need explicit indication.
- Keep normal positions, transfer limits, source independence and protection-zone boundaries visible. An arrangement drawing explains connectivity; the permitted switching sequence needs a separate approved scheme.

## Information to show or reference

- Label the source and connection reference for transfer state machine.
- Identify the destination and defined state of transfer-active status.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Intermediate states need explicit indication.

## Important distinction

Intermediate states need explicit indication. 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: Switchgear
- Input / boundary: Transfer state machine
- Output / connection: Transfer-active status
- Lookup label: ITI is a library lookup label, not a standard device designation.

## Public references

- [SEL-451 protection, automation and bay control](https://selinc.com/products/451/) — SEL. Public technical context for switchboard source and bus interfaces. Bus arrangements, breaker control and bay-level coordination. 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.