# Shutter-access interlock interface

Canonical URL: https://eloragrid.ai/symbols/shutter-access-interlock-interface
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: SII
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: switchgear
Input: Shutter and access conditions
Output: Access interlock status

Relates primary-contact shutter position to the documented access restrictions.

## In plain English

### What this block does

Relates primary-contact shutter position to the documented access restrictions.

### A simple example

In a switchgear feeder panel, a control diagram can prevent an incompatible combination of breaker, disconnector and earthing-switch positions. The physical equipment documents determine which restrictions are mechanically enforced. For this reference, the drawing identifies “Shutter and access conditions” at the input and “Access interlock status” at the output. The indication is not authorization to approach live contacts.

### What the drawings help you do

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

### Terms

- Input: Shutter and access conditions
- Output: Access interlock status
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: Shutter and access conditions → SII → Access interlock status
A reading guide. The entry's original illustration and input/output facts describe this application.

- [Masterclad medium-voltage switchgear: circuit-breaker section interlocks](https://productinfo.se.com/masterclad_mv_switchgear_ib/6055-30-masterclad-15kv-mv-switchgear-ib/English/6055-30%20Masterclad%20MV%20Switchgear%20Indoor%20%28bookmap%29_DD00646805.xml/%24/Section6-CircuitBreakerSectionInter-58DD6EC7)


## What it represents

Relates primary-contact shutter position to the documented access restrictions. An interlocking function permits or blocks an operation according to the positions and conditions of related equipment. Electrical, mechanical and trapped-key interlocks implement different parts of a coordinated operating philosophy.
In a switchgear feeder panel, a control diagram can prevent an incompatible combination of breaker, disconnector and earthing-switch positions. The physical equipment documents determine which restrictions are mechanically enforced. For this reference, the drawing identifies “Shutter and access conditions” at the input and “Access interlock status” at the output. The indication is not authorization to approach live contacts.
Identify each initiating position, the action being blocked and the consequence of missing feedback. An illustrative logic diagram must not be treated as an operating procedure or proof of a complete safety system. 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: Shutter and access conditions. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Access interlock status. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- The indication is not authorization to approach live contacts.
- Identify each initiating position, the action being blocked and the consequence of missing feedback. An illustrative logic diagram must not be treated as an operating procedure or proof of a complete safety system.

## Information to show or reference

- Label the source and connection reference for shutter and access conditions.
- Identify the destination and defined state of access interlock status.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: The indication is not authorization to approach live contacts.

## Important distinction

The indication is not authorization to approach live contacts. 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: Shutter and access conditions
- Output / connection: Access interlock status
- Lookup label: SII is a library lookup label, not a standard device designation.

## Public references

- [Masterclad medium-voltage switchgear: circuit-breaker section interlocks](https://productinfo.se.com/masterclad_mv_switchgear_ib/6055-30-masterclad-15kv-mv-switchgear-ib/English/6055-30%20Masterclad%20MV%20Switchgear%20Indoor%20%28bookmap%29_DD00646805.xml/%24/Section6-CircuitBreakerSectionInter-58DD6EC7) — Schneider Electric. Public technical context for switchgear interlocking functions. Breaker control, mechanism, position contacts, racking interlocks and test interfaces. 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.